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Introduction to Lasers
in Dermatology
Kristen Kelly MD
Clinical Professor of
Dermatology and Surgery
Beckman Laser Institute and
Medical Clinic
University of California Irvine
bull Please no photos during the presentation
bull Patient privacy needs to be protected
Lasers Applications in Medicine
bull Dermatology
ndash Blood vessel lesions
ndash Pigmented (Brown)
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Lasers Applications in Medicine
bull Neurosurgery
bull Podiatry
bull General Surgery
bull Gynecology
bull Ophthalmology
Laser Effect on Biological Tissue
bull Depends on tissue properties
bull Function of laser parameters
bull Details are not fully understood
Tissue Propertiesoptical thermal mechanical
light distribution
heat transfer
stress propagation
Laser Parameters Things a surgeon can control
Wavelength
Determines penetration depth
ldquotargets chromophorerdquo
Pulse Duration
How long the tissue is heated
Power
Energy depositionHeating rate
Use of Epidermal Cooling
Objective of Laser Skin Surgery
Target a selected light absorbing
chromophore in human skin without
damaging surrounding tissue
Epidermis
Dermis
Targeted
Chromophores
Melanin
Early Therapeutic Use of Lasers
bull Blood vessel lesion improvement
bull Significant incidence of scarring
especially in young children
Theory of Selective Photothermolysis
bull Laser energy preferentially absorbed by
one structure in tissue
ndash Melanin dermis blood tattoo ink etc
bull Surrounding tissue has low absorption
bull Selective absorption of radiant energy
bull Selective heatingdestruction of tissue
Anderson R Parrish J Science 1983 220524-527
only chromophores
absorb light
selective
photothermal
lysis
Theory of Selective Photothermolysis
bull Two parameters central to this concept
ndashWavelength
ndashPulse Duration Anderson R Parrish J Science 1983 220524-527
Wavelength
bull Laser wavelength must
approximate an absorption peak of
the targeted chromophore in
relation to other optically absorbing
molecules
bull Wavelength also determines the
depth to which light penetrates with
sufficient energy to effect tissue
change
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Selective Photothermolysis
bull Pulse duration should be on the
order of the thermal relaxation time
(TRT) of the target
bull Thermal relaxation time is the
duration required for the heat
generated by absorbed light energy
within the target chromophore to
dissipate to 50 of its value
immediately after laser exposure
Thermal Relaxation Time
bull Directly related to the size of the target
bull Inversely related to heat diffusion
of the tissue
microvessel
blood vessel
10 m
200 m
90 s
5 ms
tattoo
pigment
05-100
m 20 ns-3 ms
melanosome
melanocyte
05-10 m
7 m
20-40 ns
1 s
Target Size r
Target Chromophore Size and r
Pulse Duration of Commercially
Available Pulsed Dye Lasers
bull 450 microseconds
bull 1500 microseconds
bull 1500-40000
microseconds
Longer Pulse Durations
-Allow gentler heating of target
-Avoiding mechanical disruption of vessel and
purpura
Selective photothermolysis significantly
improved treatment outcome
However challenges remained
Multiple treatments required
Incomplete lesion removal
Treatment of darker skin types
Treatment discomfort
Problem Nonspecific epidermal (melanin) absorption
Answer Epidermal Cooling
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Cooling the Superficial Skin Layers
Target
Chromophores
Epidermal
Melanin
Cooling Medium
Dermis
Epidermis Epidermis
Dermis
Prevents epidermal injury
Leaves the dermal target susceptible
to laser induced thermal injury
Cryogen Spray Cooling Device
Contact Cooling Devices
Air Cooling Device
Epidermal Cooling
- Allows the use of higher fluences
- Allows safe treatment of darker skin
- Decreases treatment discomfort
Lasers Applications in Medicine
bull Dermatology
ndash Vascular lesions
ndash Select Pigmented
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Laser Treatment of
Vascular Skin Lesions
Laser Treatment of Vasculature
bull Chromophore Oxyhemoglobin (blood)
bull Pulse Duration Variable (1-10 milliseconds)
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
bull Please no photos during the presentation
bull Patient privacy needs to be protected
Lasers Applications in Medicine
bull Dermatology
ndash Blood vessel lesions
ndash Pigmented (Brown)
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Lasers Applications in Medicine
bull Neurosurgery
bull Podiatry
bull General Surgery
bull Gynecology
bull Ophthalmology
Laser Effect on Biological Tissue
bull Depends on tissue properties
bull Function of laser parameters
bull Details are not fully understood
Tissue Propertiesoptical thermal mechanical
light distribution
heat transfer
stress propagation
Laser Parameters Things a surgeon can control
Wavelength
Determines penetration depth
ldquotargets chromophorerdquo
Pulse Duration
How long the tissue is heated
Power
Energy depositionHeating rate
Use of Epidermal Cooling
Objective of Laser Skin Surgery
Target a selected light absorbing
chromophore in human skin without
damaging surrounding tissue
Epidermis
Dermis
Targeted
Chromophores
Melanin
Early Therapeutic Use of Lasers
bull Blood vessel lesion improvement
bull Significant incidence of scarring
especially in young children
Theory of Selective Photothermolysis
bull Laser energy preferentially absorbed by
one structure in tissue
ndash Melanin dermis blood tattoo ink etc
bull Surrounding tissue has low absorption
bull Selective absorption of radiant energy
bull Selective heatingdestruction of tissue
Anderson R Parrish J Science 1983 220524-527
only chromophores
absorb light
selective
photothermal
lysis
Theory of Selective Photothermolysis
bull Two parameters central to this concept
ndashWavelength
ndashPulse Duration Anderson R Parrish J Science 1983 220524-527
Wavelength
bull Laser wavelength must
approximate an absorption peak of
the targeted chromophore in
relation to other optically absorbing
molecules
bull Wavelength also determines the
depth to which light penetrates with
sufficient energy to effect tissue
change
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Selective Photothermolysis
bull Pulse duration should be on the
order of the thermal relaxation time
(TRT) of the target
bull Thermal relaxation time is the
duration required for the heat
generated by absorbed light energy
within the target chromophore to
dissipate to 50 of its value
immediately after laser exposure
Thermal Relaxation Time
bull Directly related to the size of the target
bull Inversely related to heat diffusion
of the tissue
microvessel
blood vessel
10 m
200 m
90 s
5 ms
tattoo
pigment
05-100
m 20 ns-3 ms
melanosome
melanocyte
05-10 m
7 m
20-40 ns
1 s
Target Size r
Target Chromophore Size and r
Pulse Duration of Commercially
Available Pulsed Dye Lasers
bull 450 microseconds
bull 1500 microseconds
bull 1500-40000
microseconds
Longer Pulse Durations
-Allow gentler heating of target
-Avoiding mechanical disruption of vessel and
purpura
Selective photothermolysis significantly
improved treatment outcome
However challenges remained
Multiple treatments required
Incomplete lesion removal
Treatment of darker skin types
Treatment discomfort
Problem Nonspecific epidermal (melanin) absorption
Answer Epidermal Cooling
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Cooling the Superficial Skin Layers
Target
Chromophores
Epidermal
Melanin
Cooling Medium
Dermis
Epidermis Epidermis
Dermis
Prevents epidermal injury
Leaves the dermal target susceptible
to laser induced thermal injury
Cryogen Spray Cooling Device
Contact Cooling Devices
Air Cooling Device
Epidermal Cooling
- Allows the use of higher fluences
- Allows safe treatment of darker skin
- Decreases treatment discomfort
Lasers Applications in Medicine
bull Dermatology
ndash Vascular lesions
ndash Select Pigmented
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Laser Treatment of
Vascular Skin Lesions
Laser Treatment of Vasculature
bull Chromophore Oxyhemoglobin (blood)
bull Pulse Duration Variable (1-10 milliseconds)
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Lasers Applications in Medicine
bull Dermatology
ndash Blood vessel lesions
ndash Pigmented (Brown)
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Lasers Applications in Medicine
bull Neurosurgery
bull Podiatry
bull General Surgery
bull Gynecology
bull Ophthalmology
Laser Effect on Biological Tissue
bull Depends on tissue properties
bull Function of laser parameters
bull Details are not fully understood
Tissue Propertiesoptical thermal mechanical
light distribution
heat transfer
stress propagation
Laser Parameters Things a surgeon can control
Wavelength
Determines penetration depth
ldquotargets chromophorerdquo
Pulse Duration
How long the tissue is heated
Power
Energy depositionHeating rate
Use of Epidermal Cooling
Objective of Laser Skin Surgery
Target a selected light absorbing
chromophore in human skin without
damaging surrounding tissue
Epidermis
Dermis
Targeted
Chromophores
Melanin
Early Therapeutic Use of Lasers
bull Blood vessel lesion improvement
bull Significant incidence of scarring
especially in young children
Theory of Selective Photothermolysis
bull Laser energy preferentially absorbed by
one structure in tissue
ndash Melanin dermis blood tattoo ink etc
bull Surrounding tissue has low absorption
bull Selective absorption of radiant energy
bull Selective heatingdestruction of tissue
Anderson R Parrish J Science 1983 220524-527
only chromophores
absorb light
selective
photothermal
lysis
Theory of Selective Photothermolysis
bull Two parameters central to this concept
ndashWavelength
ndashPulse Duration Anderson R Parrish J Science 1983 220524-527
Wavelength
bull Laser wavelength must
approximate an absorption peak of
the targeted chromophore in
relation to other optically absorbing
molecules
bull Wavelength also determines the
depth to which light penetrates with
sufficient energy to effect tissue
change
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Selective Photothermolysis
bull Pulse duration should be on the
order of the thermal relaxation time
(TRT) of the target
bull Thermal relaxation time is the
duration required for the heat
generated by absorbed light energy
within the target chromophore to
dissipate to 50 of its value
immediately after laser exposure
Thermal Relaxation Time
bull Directly related to the size of the target
bull Inversely related to heat diffusion
of the tissue
microvessel
blood vessel
10 m
200 m
90 s
5 ms
tattoo
pigment
05-100
m 20 ns-3 ms
melanosome
melanocyte
05-10 m
7 m
20-40 ns
1 s
Target Size r
Target Chromophore Size and r
Pulse Duration of Commercially
Available Pulsed Dye Lasers
bull 450 microseconds
bull 1500 microseconds
bull 1500-40000
microseconds
Longer Pulse Durations
-Allow gentler heating of target
-Avoiding mechanical disruption of vessel and
purpura
Selective photothermolysis significantly
improved treatment outcome
However challenges remained
Multiple treatments required
Incomplete lesion removal
Treatment of darker skin types
Treatment discomfort
Problem Nonspecific epidermal (melanin) absorption
Answer Epidermal Cooling
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Cooling the Superficial Skin Layers
Target
Chromophores
Epidermal
Melanin
Cooling Medium
Dermis
Epidermis Epidermis
Dermis
Prevents epidermal injury
Leaves the dermal target susceptible
to laser induced thermal injury
Cryogen Spray Cooling Device
Contact Cooling Devices
Air Cooling Device
Epidermal Cooling
- Allows the use of higher fluences
- Allows safe treatment of darker skin
- Decreases treatment discomfort
Lasers Applications in Medicine
bull Dermatology
ndash Vascular lesions
ndash Select Pigmented
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Laser Treatment of
Vascular Skin Lesions
Laser Treatment of Vasculature
bull Chromophore Oxyhemoglobin (blood)
bull Pulse Duration Variable (1-10 milliseconds)
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Lasers Applications in Medicine
bull Neurosurgery
bull Podiatry
bull General Surgery
bull Gynecology
bull Ophthalmology
Laser Effect on Biological Tissue
bull Depends on tissue properties
bull Function of laser parameters
bull Details are not fully understood
Tissue Propertiesoptical thermal mechanical
light distribution
heat transfer
stress propagation
Laser Parameters Things a surgeon can control
Wavelength
Determines penetration depth
ldquotargets chromophorerdquo
Pulse Duration
How long the tissue is heated
Power
Energy depositionHeating rate
Use of Epidermal Cooling
Objective of Laser Skin Surgery
Target a selected light absorbing
chromophore in human skin without
damaging surrounding tissue
Epidermis
Dermis
Targeted
Chromophores
Melanin
Early Therapeutic Use of Lasers
bull Blood vessel lesion improvement
bull Significant incidence of scarring
especially in young children
Theory of Selective Photothermolysis
bull Laser energy preferentially absorbed by
one structure in tissue
ndash Melanin dermis blood tattoo ink etc
bull Surrounding tissue has low absorption
bull Selective absorption of radiant energy
bull Selective heatingdestruction of tissue
Anderson R Parrish J Science 1983 220524-527
only chromophores
absorb light
selective
photothermal
lysis
Theory of Selective Photothermolysis
bull Two parameters central to this concept
ndashWavelength
ndashPulse Duration Anderson R Parrish J Science 1983 220524-527
Wavelength
bull Laser wavelength must
approximate an absorption peak of
the targeted chromophore in
relation to other optically absorbing
molecules
bull Wavelength also determines the
depth to which light penetrates with
sufficient energy to effect tissue
change
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Selective Photothermolysis
bull Pulse duration should be on the
order of the thermal relaxation time
(TRT) of the target
bull Thermal relaxation time is the
duration required for the heat
generated by absorbed light energy
within the target chromophore to
dissipate to 50 of its value
immediately after laser exposure
Thermal Relaxation Time
bull Directly related to the size of the target
bull Inversely related to heat diffusion
of the tissue
microvessel
blood vessel
10 m
200 m
90 s
5 ms
tattoo
pigment
05-100
m 20 ns-3 ms
melanosome
melanocyte
05-10 m
7 m
20-40 ns
1 s
Target Size r
Target Chromophore Size and r
Pulse Duration of Commercially
Available Pulsed Dye Lasers
bull 450 microseconds
bull 1500 microseconds
bull 1500-40000
microseconds
Longer Pulse Durations
-Allow gentler heating of target
-Avoiding mechanical disruption of vessel and
purpura
Selective photothermolysis significantly
improved treatment outcome
However challenges remained
Multiple treatments required
Incomplete lesion removal
Treatment of darker skin types
Treatment discomfort
Problem Nonspecific epidermal (melanin) absorption
Answer Epidermal Cooling
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Cooling the Superficial Skin Layers
Target
Chromophores
Epidermal
Melanin
Cooling Medium
Dermis
Epidermis Epidermis
Dermis
Prevents epidermal injury
Leaves the dermal target susceptible
to laser induced thermal injury
Cryogen Spray Cooling Device
Contact Cooling Devices
Air Cooling Device
Epidermal Cooling
- Allows the use of higher fluences
- Allows safe treatment of darker skin
- Decreases treatment discomfort
Lasers Applications in Medicine
bull Dermatology
ndash Vascular lesions
ndash Select Pigmented
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Laser Treatment of
Vascular Skin Lesions
Laser Treatment of Vasculature
bull Chromophore Oxyhemoglobin (blood)
bull Pulse Duration Variable (1-10 milliseconds)
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Laser Effect on Biological Tissue
bull Depends on tissue properties
bull Function of laser parameters
bull Details are not fully understood
Tissue Propertiesoptical thermal mechanical
light distribution
heat transfer
stress propagation
Laser Parameters Things a surgeon can control
Wavelength
Determines penetration depth
ldquotargets chromophorerdquo
Pulse Duration
How long the tissue is heated
Power
Energy depositionHeating rate
Use of Epidermal Cooling
Objective of Laser Skin Surgery
Target a selected light absorbing
chromophore in human skin without
damaging surrounding tissue
Epidermis
Dermis
Targeted
Chromophores
Melanin
Early Therapeutic Use of Lasers
bull Blood vessel lesion improvement
bull Significant incidence of scarring
especially in young children
Theory of Selective Photothermolysis
bull Laser energy preferentially absorbed by
one structure in tissue
ndash Melanin dermis blood tattoo ink etc
bull Surrounding tissue has low absorption
bull Selective absorption of radiant energy
bull Selective heatingdestruction of tissue
Anderson R Parrish J Science 1983 220524-527
only chromophores
absorb light
selective
photothermal
lysis
Theory of Selective Photothermolysis
bull Two parameters central to this concept
ndashWavelength
ndashPulse Duration Anderson R Parrish J Science 1983 220524-527
Wavelength
bull Laser wavelength must
approximate an absorption peak of
the targeted chromophore in
relation to other optically absorbing
molecules
bull Wavelength also determines the
depth to which light penetrates with
sufficient energy to effect tissue
change
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Selective Photothermolysis
bull Pulse duration should be on the
order of the thermal relaxation time
(TRT) of the target
bull Thermal relaxation time is the
duration required for the heat
generated by absorbed light energy
within the target chromophore to
dissipate to 50 of its value
immediately after laser exposure
Thermal Relaxation Time
bull Directly related to the size of the target
bull Inversely related to heat diffusion
of the tissue
microvessel
blood vessel
10 m
200 m
90 s
5 ms
tattoo
pigment
05-100
m 20 ns-3 ms
melanosome
melanocyte
05-10 m
7 m
20-40 ns
1 s
Target Size r
Target Chromophore Size and r
Pulse Duration of Commercially
Available Pulsed Dye Lasers
bull 450 microseconds
bull 1500 microseconds
bull 1500-40000
microseconds
Longer Pulse Durations
-Allow gentler heating of target
-Avoiding mechanical disruption of vessel and
purpura
Selective photothermolysis significantly
improved treatment outcome
However challenges remained
Multiple treatments required
Incomplete lesion removal
Treatment of darker skin types
Treatment discomfort
Problem Nonspecific epidermal (melanin) absorption
Answer Epidermal Cooling
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Cooling the Superficial Skin Layers
Target
Chromophores
Epidermal
Melanin
Cooling Medium
Dermis
Epidermis Epidermis
Dermis
Prevents epidermal injury
Leaves the dermal target susceptible
to laser induced thermal injury
Cryogen Spray Cooling Device
Contact Cooling Devices
Air Cooling Device
Epidermal Cooling
- Allows the use of higher fluences
- Allows safe treatment of darker skin
- Decreases treatment discomfort
Lasers Applications in Medicine
bull Dermatology
ndash Vascular lesions
ndash Select Pigmented
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Laser Treatment of
Vascular Skin Lesions
Laser Treatment of Vasculature
bull Chromophore Oxyhemoglobin (blood)
bull Pulse Duration Variable (1-10 milliseconds)
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Tissue Propertiesoptical thermal mechanical
light distribution
heat transfer
stress propagation
Laser Parameters Things a surgeon can control
Wavelength
Determines penetration depth
ldquotargets chromophorerdquo
Pulse Duration
How long the tissue is heated
Power
Energy depositionHeating rate
Use of Epidermal Cooling
Objective of Laser Skin Surgery
Target a selected light absorbing
chromophore in human skin without
damaging surrounding tissue
Epidermis
Dermis
Targeted
Chromophores
Melanin
Early Therapeutic Use of Lasers
bull Blood vessel lesion improvement
bull Significant incidence of scarring
especially in young children
Theory of Selective Photothermolysis
bull Laser energy preferentially absorbed by
one structure in tissue
ndash Melanin dermis blood tattoo ink etc
bull Surrounding tissue has low absorption
bull Selective absorption of radiant energy
bull Selective heatingdestruction of tissue
Anderson R Parrish J Science 1983 220524-527
only chromophores
absorb light
selective
photothermal
lysis
Theory of Selective Photothermolysis
bull Two parameters central to this concept
ndashWavelength
ndashPulse Duration Anderson R Parrish J Science 1983 220524-527
Wavelength
bull Laser wavelength must
approximate an absorption peak of
the targeted chromophore in
relation to other optically absorbing
molecules
bull Wavelength also determines the
depth to which light penetrates with
sufficient energy to effect tissue
change
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Selective Photothermolysis
bull Pulse duration should be on the
order of the thermal relaxation time
(TRT) of the target
bull Thermal relaxation time is the
duration required for the heat
generated by absorbed light energy
within the target chromophore to
dissipate to 50 of its value
immediately after laser exposure
Thermal Relaxation Time
bull Directly related to the size of the target
bull Inversely related to heat diffusion
of the tissue
microvessel
blood vessel
10 m
200 m
90 s
5 ms
tattoo
pigment
05-100
m 20 ns-3 ms
melanosome
melanocyte
05-10 m
7 m
20-40 ns
1 s
Target Size r
Target Chromophore Size and r
Pulse Duration of Commercially
Available Pulsed Dye Lasers
bull 450 microseconds
bull 1500 microseconds
bull 1500-40000
microseconds
Longer Pulse Durations
-Allow gentler heating of target
-Avoiding mechanical disruption of vessel and
purpura
Selective photothermolysis significantly
improved treatment outcome
However challenges remained
Multiple treatments required
Incomplete lesion removal
Treatment of darker skin types
Treatment discomfort
Problem Nonspecific epidermal (melanin) absorption
Answer Epidermal Cooling
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Cooling the Superficial Skin Layers
Target
Chromophores
Epidermal
Melanin
Cooling Medium
Dermis
Epidermis Epidermis
Dermis
Prevents epidermal injury
Leaves the dermal target susceptible
to laser induced thermal injury
Cryogen Spray Cooling Device
Contact Cooling Devices
Air Cooling Device
Epidermal Cooling
- Allows the use of higher fluences
- Allows safe treatment of darker skin
- Decreases treatment discomfort
Lasers Applications in Medicine
bull Dermatology
ndash Vascular lesions
ndash Select Pigmented
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Laser Treatment of
Vascular Skin Lesions
Laser Treatment of Vasculature
bull Chromophore Oxyhemoglobin (blood)
bull Pulse Duration Variable (1-10 milliseconds)
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Laser Parameters Things a surgeon can control
Wavelength
Determines penetration depth
ldquotargets chromophorerdquo
Pulse Duration
How long the tissue is heated
Power
Energy depositionHeating rate
Use of Epidermal Cooling
Objective of Laser Skin Surgery
Target a selected light absorbing
chromophore in human skin without
damaging surrounding tissue
Epidermis
Dermis
Targeted
Chromophores
Melanin
Early Therapeutic Use of Lasers
bull Blood vessel lesion improvement
bull Significant incidence of scarring
especially in young children
Theory of Selective Photothermolysis
bull Laser energy preferentially absorbed by
one structure in tissue
ndash Melanin dermis blood tattoo ink etc
bull Surrounding tissue has low absorption
bull Selective absorption of radiant energy
bull Selective heatingdestruction of tissue
Anderson R Parrish J Science 1983 220524-527
only chromophores
absorb light
selective
photothermal
lysis
Theory of Selective Photothermolysis
bull Two parameters central to this concept
ndashWavelength
ndashPulse Duration Anderson R Parrish J Science 1983 220524-527
Wavelength
bull Laser wavelength must
approximate an absorption peak of
the targeted chromophore in
relation to other optically absorbing
molecules
bull Wavelength also determines the
depth to which light penetrates with
sufficient energy to effect tissue
change
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Selective Photothermolysis
bull Pulse duration should be on the
order of the thermal relaxation time
(TRT) of the target
bull Thermal relaxation time is the
duration required for the heat
generated by absorbed light energy
within the target chromophore to
dissipate to 50 of its value
immediately after laser exposure
Thermal Relaxation Time
bull Directly related to the size of the target
bull Inversely related to heat diffusion
of the tissue
microvessel
blood vessel
10 m
200 m
90 s
5 ms
tattoo
pigment
05-100
m 20 ns-3 ms
melanosome
melanocyte
05-10 m
7 m
20-40 ns
1 s
Target Size r
Target Chromophore Size and r
Pulse Duration of Commercially
Available Pulsed Dye Lasers
bull 450 microseconds
bull 1500 microseconds
bull 1500-40000
microseconds
Longer Pulse Durations
-Allow gentler heating of target
-Avoiding mechanical disruption of vessel and
purpura
Selective photothermolysis significantly
improved treatment outcome
However challenges remained
Multiple treatments required
Incomplete lesion removal
Treatment of darker skin types
Treatment discomfort
Problem Nonspecific epidermal (melanin) absorption
Answer Epidermal Cooling
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Cooling the Superficial Skin Layers
Target
Chromophores
Epidermal
Melanin
Cooling Medium
Dermis
Epidermis Epidermis
Dermis
Prevents epidermal injury
Leaves the dermal target susceptible
to laser induced thermal injury
Cryogen Spray Cooling Device
Contact Cooling Devices
Air Cooling Device
Epidermal Cooling
- Allows the use of higher fluences
- Allows safe treatment of darker skin
- Decreases treatment discomfort
Lasers Applications in Medicine
bull Dermatology
ndash Vascular lesions
ndash Select Pigmented
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Laser Treatment of
Vascular Skin Lesions
Laser Treatment of Vasculature
bull Chromophore Oxyhemoglobin (blood)
bull Pulse Duration Variable (1-10 milliseconds)
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Objective of Laser Skin Surgery
Target a selected light absorbing
chromophore in human skin without
damaging surrounding tissue
Epidermis
Dermis
Targeted
Chromophores
Melanin
Early Therapeutic Use of Lasers
bull Blood vessel lesion improvement
bull Significant incidence of scarring
especially in young children
Theory of Selective Photothermolysis
bull Laser energy preferentially absorbed by
one structure in tissue
ndash Melanin dermis blood tattoo ink etc
bull Surrounding tissue has low absorption
bull Selective absorption of radiant energy
bull Selective heatingdestruction of tissue
Anderson R Parrish J Science 1983 220524-527
only chromophores
absorb light
selective
photothermal
lysis
Theory of Selective Photothermolysis
bull Two parameters central to this concept
ndashWavelength
ndashPulse Duration Anderson R Parrish J Science 1983 220524-527
Wavelength
bull Laser wavelength must
approximate an absorption peak of
the targeted chromophore in
relation to other optically absorbing
molecules
bull Wavelength also determines the
depth to which light penetrates with
sufficient energy to effect tissue
change
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Selective Photothermolysis
bull Pulse duration should be on the
order of the thermal relaxation time
(TRT) of the target
bull Thermal relaxation time is the
duration required for the heat
generated by absorbed light energy
within the target chromophore to
dissipate to 50 of its value
immediately after laser exposure
Thermal Relaxation Time
bull Directly related to the size of the target
bull Inversely related to heat diffusion
of the tissue
microvessel
blood vessel
10 m
200 m
90 s
5 ms
tattoo
pigment
05-100
m 20 ns-3 ms
melanosome
melanocyte
05-10 m
7 m
20-40 ns
1 s
Target Size r
Target Chromophore Size and r
Pulse Duration of Commercially
Available Pulsed Dye Lasers
bull 450 microseconds
bull 1500 microseconds
bull 1500-40000
microseconds
Longer Pulse Durations
-Allow gentler heating of target
-Avoiding mechanical disruption of vessel and
purpura
Selective photothermolysis significantly
improved treatment outcome
However challenges remained
Multiple treatments required
Incomplete lesion removal
Treatment of darker skin types
Treatment discomfort
Problem Nonspecific epidermal (melanin) absorption
Answer Epidermal Cooling
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Cooling the Superficial Skin Layers
Target
Chromophores
Epidermal
Melanin
Cooling Medium
Dermis
Epidermis Epidermis
Dermis
Prevents epidermal injury
Leaves the dermal target susceptible
to laser induced thermal injury
Cryogen Spray Cooling Device
Contact Cooling Devices
Air Cooling Device
Epidermal Cooling
- Allows the use of higher fluences
- Allows safe treatment of darker skin
- Decreases treatment discomfort
Lasers Applications in Medicine
bull Dermatology
ndash Vascular lesions
ndash Select Pigmented
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Laser Treatment of
Vascular Skin Lesions
Laser Treatment of Vasculature
bull Chromophore Oxyhemoglobin (blood)
bull Pulse Duration Variable (1-10 milliseconds)
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Early Therapeutic Use of Lasers
bull Blood vessel lesion improvement
bull Significant incidence of scarring
especially in young children
Theory of Selective Photothermolysis
bull Laser energy preferentially absorbed by
one structure in tissue
ndash Melanin dermis blood tattoo ink etc
bull Surrounding tissue has low absorption
bull Selective absorption of radiant energy
bull Selective heatingdestruction of tissue
Anderson R Parrish J Science 1983 220524-527
only chromophores
absorb light
selective
photothermal
lysis
Theory of Selective Photothermolysis
bull Two parameters central to this concept
ndashWavelength
ndashPulse Duration Anderson R Parrish J Science 1983 220524-527
Wavelength
bull Laser wavelength must
approximate an absorption peak of
the targeted chromophore in
relation to other optically absorbing
molecules
bull Wavelength also determines the
depth to which light penetrates with
sufficient energy to effect tissue
change
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Selective Photothermolysis
bull Pulse duration should be on the
order of the thermal relaxation time
(TRT) of the target
bull Thermal relaxation time is the
duration required for the heat
generated by absorbed light energy
within the target chromophore to
dissipate to 50 of its value
immediately after laser exposure
Thermal Relaxation Time
bull Directly related to the size of the target
bull Inversely related to heat diffusion
of the tissue
microvessel
blood vessel
10 m
200 m
90 s
5 ms
tattoo
pigment
05-100
m 20 ns-3 ms
melanosome
melanocyte
05-10 m
7 m
20-40 ns
1 s
Target Size r
Target Chromophore Size and r
Pulse Duration of Commercially
Available Pulsed Dye Lasers
bull 450 microseconds
bull 1500 microseconds
bull 1500-40000
microseconds
Longer Pulse Durations
-Allow gentler heating of target
-Avoiding mechanical disruption of vessel and
purpura
Selective photothermolysis significantly
improved treatment outcome
However challenges remained
Multiple treatments required
Incomplete lesion removal
Treatment of darker skin types
Treatment discomfort
Problem Nonspecific epidermal (melanin) absorption
Answer Epidermal Cooling
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Cooling the Superficial Skin Layers
Target
Chromophores
Epidermal
Melanin
Cooling Medium
Dermis
Epidermis Epidermis
Dermis
Prevents epidermal injury
Leaves the dermal target susceptible
to laser induced thermal injury
Cryogen Spray Cooling Device
Contact Cooling Devices
Air Cooling Device
Epidermal Cooling
- Allows the use of higher fluences
- Allows safe treatment of darker skin
- Decreases treatment discomfort
Lasers Applications in Medicine
bull Dermatology
ndash Vascular lesions
ndash Select Pigmented
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Laser Treatment of
Vascular Skin Lesions
Laser Treatment of Vasculature
bull Chromophore Oxyhemoglobin (blood)
bull Pulse Duration Variable (1-10 milliseconds)
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Theory of Selective Photothermolysis
bull Laser energy preferentially absorbed by
one structure in tissue
ndash Melanin dermis blood tattoo ink etc
bull Surrounding tissue has low absorption
bull Selective absorption of radiant energy
bull Selective heatingdestruction of tissue
Anderson R Parrish J Science 1983 220524-527
only chromophores
absorb light
selective
photothermal
lysis
Theory of Selective Photothermolysis
bull Two parameters central to this concept
ndashWavelength
ndashPulse Duration Anderson R Parrish J Science 1983 220524-527
Wavelength
bull Laser wavelength must
approximate an absorption peak of
the targeted chromophore in
relation to other optically absorbing
molecules
bull Wavelength also determines the
depth to which light penetrates with
sufficient energy to effect tissue
change
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Selective Photothermolysis
bull Pulse duration should be on the
order of the thermal relaxation time
(TRT) of the target
bull Thermal relaxation time is the
duration required for the heat
generated by absorbed light energy
within the target chromophore to
dissipate to 50 of its value
immediately after laser exposure
Thermal Relaxation Time
bull Directly related to the size of the target
bull Inversely related to heat diffusion
of the tissue
microvessel
blood vessel
10 m
200 m
90 s
5 ms
tattoo
pigment
05-100
m 20 ns-3 ms
melanosome
melanocyte
05-10 m
7 m
20-40 ns
1 s
Target Size r
Target Chromophore Size and r
Pulse Duration of Commercially
Available Pulsed Dye Lasers
bull 450 microseconds
bull 1500 microseconds
bull 1500-40000
microseconds
Longer Pulse Durations
-Allow gentler heating of target
-Avoiding mechanical disruption of vessel and
purpura
Selective photothermolysis significantly
improved treatment outcome
However challenges remained
Multiple treatments required
Incomplete lesion removal
Treatment of darker skin types
Treatment discomfort
Problem Nonspecific epidermal (melanin) absorption
Answer Epidermal Cooling
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Cooling the Superficial Skin Layers
Target
Chromophores
Epidermal
Melanin
Cooling Medium
Dermis
Epidermis Epidermis
Dermis
Prevents epidermal injury
Leaves the dermal target susceptible
to laser induced thermal injury
Cryogen Spray Cooling Device
Contact Cooling Devices
Air Cooling Device
Epidermal Cooling
- Allows the use of higher fluences
- Allows safe treatment of darker skin
- Decreases treatment discomfort
Lasers Applications in Medicine
bull Dermatology
ndash Vascular lesions
ndash Select Pigmented
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Laser Treatment of
Vascular Skin Lesions
Laser Treatment of Vasculature
bull Chromophore Oxyhemoglobin (blood)
bull Pulse Duration Variable (1-10 milliseconds)
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
only chromophores
absorb light
selective
photothermal
lysis
Theory of Selective Photothermolysis
bull Two parameters central to this concept
ndashWavelength
ndashPulse Duration Anderson R Parrish J Science 1983 220524-527
Wavelength
bull Laser wavelength must
approximate an absorption peak of
the targeted chromophore in
relation to other optically absorbing
molecules
bull Wavelength also determines the
depth to which light penetrates with
sufficient energy to effect tissue
change
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Selective Photothermolysis
bull Pulse duration should be on the
order of the thermal relaxation time
(TRT) of the target
bull Thermal relaxation time is the
duration required for the heat
generated by absorbed light energy
within the target chromophore to
dissipate to 50 of its value
immediately after laser exposure
Thermal Relaxation Time
bull Directly related to the size of the target
bull Inversely related to heat diffusion
of the tissue
microvessel
blood vessel
10 m
200 m
90 s
5 ms
tattoo
pigment
05-100
m 20 ns-3 ms
melanosome
melanocyte
05-10 m
7 m
20-40 ns
1 s
Target Size r
Target Chromophore Size and r
Pulse Duration of Commercially
Available Pulsed Dye Lasers
bull 450 microseconds
bull 1500 microseconds
bull 1500-40000
microseconds
Longer Pulse Durations
-Allow gentler heating of target
-Avoiding mechanical disruption of vessel and
purpura
Selective photothermolysis significantly
improved treatment outcome
However challenges remained
Multiple treatments required
Incomplete lesion removal
Treatment of darker skin types
Treatment discomfort
Problem Nonspecific epidermal (melanin) absorption
Answer Epidermal Cooling
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Cooling the Superficial Skin Layers
Target
Chromophores
Epidermal
Melanin
Cooling Medium
Dermis
Epidermis Epidermis
Dermis
Prevents epidermal injury
Leaves the dermal target susceptible
to laser induced thermal injury
Cryogen Spray Cooling Device
Contact Cooling Devices
Air Cooling Device
Epidermal Cooling
- Allows the use of higher fluences
- Allows safe treatment of darker skin
- Decreases treatment discomfort
Lasers Applications in Medicine
bull Dermatology
ndash Vascular lesions
ndash Select Pigmented
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Laser Treatment of
Vascular Skin Lesions
Laser Treatment of Vasculature
bull Chromophore Oxyhemoglobin (blood)
bull Pulse Duration Variable (1-10 milliseconds)
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Theory of Selective Photothermolysis
bull Two parameters central to this concept
ndashWavelength
ndashPulse Duration Anderson R Parrish J Science 1983 220524-527
Wavelength
bull Laser wavelength must
approximate an absorption peak of
the targeted chromophore in
relation to other optically absorbing
molecules
bull Wavelength also determines the
depth to which light penetrates with
sufficient energy to effect tissue
change
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Selective Photothermolysis
bull Pulse duration should be on the
order of the thermal relaxation time
(TRT) of the target
bull Thermal relaxation time is the
duration required for the heat
generated by absorbed light energy
within the target chromophore to
dissipate to 50 of its value
immediately after laser exposure
Thermal Relaxation Time
bull Directly related to the size of the target
bull Inversely related to heat diffusion
of the tissue
microvessel
blood vessel
10 m
200 m
90 s
5 ms
tattoo
pigment
05-100
m 20 ns-3 ms
melanosome
melanocyte
05-10 m
7 m
20-40 ns
1 s
Target Size r
Target Chromophore Size and r
Pulse Duration of Commercially
Available Pulsed Dye Lasers
bull 450 microseconds
bull 1500 microseconds
bull 1500-40000
microseconds
Longer Pulse Durations
-Allow gentler heating of target
-Avoiding mechanical disruption of vessel and
purpura
Selective photothermolysis significantly
improved treatment outcome
However challenges remained
Multiple treatments required
Incomplete lesion removal
Treatment of darker skin types
Treatment discomfort
Problem Nonspecific epidermal (melanin) absorption
Answer Epidermal Cooling
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Cooling the Superficial Skin Layers
Target
Chromophores
Epidermal
Melanin
Cooling Medium
Dermis
Epidermis Epidermis
Dermis
Prevents epidermal injury
Leaves the dermal target susceptible
to laser induced thermal injury
Cryogen Spray Cooling Device
Contact Cooling Devices
Air Cooling Device
Epidermal Cooling
- Allows the use of higher fluences
- Allows safe treatment of darker skin
- Decreases treatment discomfort
Lasers Applications in Medicine
bull Dermatology
ndash Vascular lesions
ndash Select Pigmented
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Laser Treatment of
Vascular Skin Lesions
Laser Treatment of Vasculature
bull Chromophore Oxyhemoglobin (blood)
bull Pulse Duration Variable (1-10 milliseconds)
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Wavelength
bull Laser wavelength must
approximate an absorption peak of
the targeted chromophore in
relation to other optically absorbing
molecules
bull Wavelength also determines the
depth to which light penetrates with
sufficient energy to effect tissue
change
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Selective Photothermolysis
bull Pulse duration should be on the
order of the thermal relaxation time
(TRT) of the target
bull Thermal relaxation time is the
duration required for the heat
generated by absorbed light energy
within the target chromophore to
dissipate to 50 of its value
immediately after laser exposure
Thermal Relaxation Time
bull Directly related to the size of the target
bull Inversely related to heat diffusion
of the tissue
microvessel
blood vessel
10 m
200 m
90 s
5 ms
tattoo
pigment
05-100
m 20 ns-3 ms
melanosome
melanocyte
05-10 m
7 m
20-40 ns
1 s
Target Size r
Target Chromophore Size and r
Pulse Duration of Commercially
Available Pulsed Dye Lasers
bull 450 microseconds
bull 1500 microseconds
bull 1500-40000
microseconds
Longer Pulse Durations
-Allow gentler heating of target
-Avoiding mechanical disruption of vessel and
purpura
Selective photothermolysis significantly
improved treatment outcome
However challenges remained
Multiple treatments required
Incomplete lesion removal
Treatment of darker skin types
Treatment discomfort
Problem Nonspecific epidermal (melanin) absorption
Answer Epidermal Cooling
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Cooling the Superficial Skin Layers
Target
Chromophores
Epidermal
Melanin
Cooling Medium
Dermis
Epidermis Epidermis
Dermis
Prevents epidermal injury
Leaves the dermal target susceptible
to laser induced thermal injury
Cryogen Spray Cooling Device
Contact Cooling Devices
Air Cooling Device
Epidermal Cooling
- Allows the use of higher fluences
- Allows safe treatment of darker skin
- Decreases treatment discomfort
Lasers Applications in Medicine
bull Dermatology
ndash Vascular lesions
ndash Select Pigmented
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Laser Treatment of
Vascular Skin Lesions
Laser Treatment of Vasculature
bull Chromophore Oxyhemoglobin (blood)
bull Pulse Duration Variable (1-10 milliseconds)
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Selective Photothermolysis
bull Pulse duration should be on the
order of the thermal relaxation time
(TRT) of the target
bull Thermal relaxation time is the
duration required for the heat
generated by absorbed light energy
within the target chromophore to
dissipate to 50 of its value
immediately after laser exposure
Thermal Relaxation Time
bull Directly related to the size of the target
bull Inversely related to heat diffusion
of the tissue
microvessel
blood vessel
10 m
200 m
90 s
5 ms
tattoo
pigment
05-100
m 20 ns-3 ms
melanosome
melanocyte
05-10 m
7 m
20-40 ns
1 s
Target Size r
Target Chromophore Size and r
Pulse Duration of Commercially
Available Pulsed Dye Lasers
bull 450 microseconds
bull 1500 microseconds
bull 1500-40000
microseconds
Longer Pulse Durations
-Allow gentler heating of target
-Avoiding mechanical disruption of vessel and
purpura
Selective photothermolysis significantly
improved treatment outcome
However challenges remained
Multiple treatments required
Incomplete lesion removal
Treatment of darker skin types
Treatment discomfort
Problem Nonspecific epidermal (melanin) absorption
Answer Epidermal Cooling
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Cooling the Superficial Skin Layers
Target
Chromophores
Epidermal
Melanin
Cooling Medium
Dermis
Epidermis Epidermis
Dermis
Prevents epidermal injury
Leaves the dermal target susceptible
to laser induced thermal injury
Cryogen Spray Cooling Device
Contact Cooling Devices
Air Cooling Device
Epidermal Cooling
- Allows the use of higher fluences
- Allows safe treatment of darker skin
- Decreases treatment discomfort
Lasers Applications in Medicine
bull Dermatology
ndash Vascular lesions
ndash Select Pigmented
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Laser Treatment of
Vascular Skin Lesions
Laser Treatment of Vasculature
bull Chromophore Oxyhemoglobin (blood)
bull Pulse Duration Variable (1-10 milliseconds)
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Selective Photothermolysis
bull Pulse duration should be on the
order of the thermal relaxation time
(TRT) of the target
bull Thermal relaxation time is the
duration required for the heat
generated by absorbed light energy
within the target chromophore to
dissipate to 50 of its value
immediately after laser exposure
Thermal Relaxation Time
bull Directly related to the size of the target
bull Inversely related to heat diffusion
of the tissue
microvessel
blood vessel
10 m
200 m
90 s
5 ms
tattoo
pigment
05-100
m 20 ns-3 ms
melanosome
melanocyte
05-10 m
7 m
20-40 ns
1 s
Target Size r
Target Chromophore Size and r
Pulse Duration of Commercially
Available Pulsed Dye Lasers
bull 450 microseconds
bull 1500 microseconds
bull 1500-40000
microseconds
Longer Pulse Durations
-Allow gentler heating of target
-Avoiding mechanical disruption of vessel and
purpura
Selective photothermolysis significantly
improved treatment outcome
However challenges remained
Multiple treatments required
Incomplete lesion removal
Treatment of darker skin types
Treatment discomfort
Problem Nonspecific epidermal (melanin) absorption
Answer Epidermal Cooling
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Cooling the Superficial Skin Layers
Target
Chromophores
Epidermal
Melanin
Cooling Medium
Dermis
Epidermis Epidermis
Dermis
Prevents epidermal injury
Leaves the dermal target susceptible
to laser induced thermal injury
Cryogen Spray Cooling Device
Contact Cooling Devices
Air Cooling Device
Epidermal Cooling
- Allows the use of higher fluences
- Allows safe treatment of darker skin
- Decreases treatment discomfort
Lasers Applications in Medicine
bull Dermatology
ndash Vascular lesions
ndash Select Pigmented
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Laser Treatment of
Vascular Skin Lesions
Laser Treatment of Vasculature
bull Chromophore Oxyhemoglobin (blood)
bull Pulse Duration Variable (1-10 milliseconds)
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Thermal Relaxation Time
bull Directly related to the size of the target
bull Inversely related to heat diffusion
of the tissue
microvessel
blood vessel
10 m
200 m
90 s
5 ms
tattoo
pigment
05-100
m 20 ns-3 ms
melanosome
melanocyte
05-10 m
7 m
20-40 ns
1 s
Target Size r
Target Chromophore Size and r
Pulse Duration of Commercially
Available Pulsed Dye Lasers
bull 450 microseconds
bull 1500 microseconds
bull 1500-40000
microseconds
Longer Pulse Durations
-Allow gentler heating of target
-Avoiding mechanical disruption of vessel and
purpura
Selective photothermolysis significantly
improved treatment outcome
However challenges remained
Multiple treatments required
Incomplete lesion removal
Treatment of darker skin types
Treatment discomfort
Problem Nonspecific epidermal (melanin) absorption
Answer Epidermal Cooling
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Cooling the Superficial Skin Layers
Target
Chromophores
Epidermal
Melanin
Cooling Medium
Dermis
Epidermis Epidermis
Dermis
Prevents epidermal injury
Leaves the dermal target susceptible
to laser induced thermal injury
Cryogen Spray Cooling Device
Contact Cooling Devices
Air Cooling Device
Epidermal Cooling
- Allows the use of higher fluences
- Allows safe treatment of darker skin
- Decreases treatment discomfort
Lasers Applications in Medicine
bull Dermatology
ndash Vascular lesions
ndash Select Pigmented
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Laser Treatment of
Vascular Skin Lesions
Laser Treatment of Vasculature
bull Chromophore Oxyhemoglobin (blood)
bull Pulse Duration Variable (1-10 milliseconds)
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
microvessel
blood vessel
10 m
200 m
90 s
5 ms
tattoo
pigment
05-100
m 20 ns-3 ms
melanosome
melanocyte
05-10 m
7 m
20-40 ns
1 s
Target Size r
Target Chromophore Size and r
Pulse Duration of Commercially
Available Pulsed Dye Lasers
bull 450 microseconds
bull 1500 microseconds
bull 1500-40000
microseconds
Longer Pulse Durations
-Allow gentler heating of target
-Avoiding mechanical disruption of vessel and
purpura
Selective photothermolysis significantly
improved treatment outcome
However challenges remained
Multiple treatments required
Incomplete lesion removal
Treatment of darker skin types
Treatment discomfort
Problem Nonspecific epidermal (melanin) absorption
Answer Epidermal Cooling
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Cooling the Superficial Skin Layers
Target
Chromophores
Epidermal
Melanin
Cooling Medium
Dermis
Epidermis Epidermis
Dermis
Prevents epidermal injury
Leaves the dermal target susceptible
to laser induced thermal injury
Cryogen Spray Cooling Device
Contact Cooling Devices
Air Cooling Device
Epidermal Cooling
- Allows the use of higher fluences
- Allows safe treatment of darker skin
- Decreases treatment discomfort
Lasers Applications in Medicine
bull Dermatology
ndash Vascular lesions
ndash Select Pigmented
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Laser Treatment of
Vascular Skin Lesions
Laser Treatment of Vasculature
bull Chromophore Oxyhemoglobin (blood)
bull Pulse Duration Variable (1-10 milliseconds)
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Pulse Duration of Commercially
Available Pulsed Dye Lasers
bull 450 microseconds
bull 1500 microseconds
bull 1500-40000
microseconds
Longer Pulse Durations
-Allow gentler heating of target
-Avoiding mechanical disruption of vessel and
purpura
Selective photothermolysis significantly
improved treatment outcome
However challenges remained
Multiple treatments required
Incomplete lesion removal
Treatment of darker skin types
Treatment discomfort
Problem Nonspecific epidermal (melanin) absorption
Answer Epidermal Cooling
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Cooling the Superficial Skin Layers
Target
Chromophores
Epidermal
Melanin
Cooling Medium
Dermis
Epidermis Epidermis
Dermis
Prevents epidermal injury
Leaves the dermal target susceptible
to laser induced thermal injury
Cryogen Spray Cooling Device
Contact Cooling Devices
Air Cooling Device
Epidermal Cooling
- Allows the use of higher fluences
- Allows safe treatment of darker skin
- Decreases treatment discomfort
Lasers Applications in Medicine
bull Dermatology
ndash Vascular lesions
ndash Select Pigmented
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Laser Treatment of
Vascular Skin Lesions
Laser Treatment of Vasculature
bull Chromophore Oxyhemoglobin (blood)
bull Pulse Duration Variable (1-10 milliseconds)
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Longer Pulse Durations
-Allow gentler heating of target
-Avoiding mechanical disruption of vessel and
purpura
Selective photothermolysis significantly
improved treatment outcome
However challenges remained
Multiple treatments required
Incomplete lesion removal
Treatment of darker skin types
Treatment discomfort
Problem Nonspecific epidermal (melanin) absorption
Answer Epidermal Cooling
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Cooling the Superficial Skin Layers
Target
Chromophores
Epidermal
Melanin
Cooling Medium
Dermis
Epidermis Epidermis
Dermis
Prevents epidermal injury
Leaves the dermal target susceptible
to laser induced thermal injury
Cryogen Spray Cooling Device
Contact Cooling Devices
Air Cooling Device
Epidermal Cooling
- Allows the use of higher fluences
- Allows safe treatment of darker skin
- Decreases treatment discomfort
Lasers Applications in Medicine
bull Dermatology
ndash Vascular lesions
ndash Select Pigmented
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Laser Treatment of
Vascular Skin Lesions
Laser Treatment of Vasculature
bull Chromophore Oxyhemoglobin (blood)
bull Pulse Duration Variable (1-10 milliseconds)
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Selective photothermolysis significantly
improved treatment outcome
However challenges remained
Multiple treatments required
Incomplete lesion removal
Treatment of darker skin types
Treatment discomfort
Problem Nonspecific epidermal (melanin) absorption
Answer Epidermal Cooling
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Cooling the Superficial Skin Layers
Target
Chromophores
Epidermal
Melanin
Cooling Medium
Dermis
Epidermis Epidermis
Dermis
Prevents epidermal injury
Leaves the dermal target susceptible
to laser induced thermal injury
Cryogen Spray Cooling Device
Contact Cooling Devices
Air Cooling Device
Epidermal Cooling
- Allows the use of higher fluences
- Allows safe treatment of darker skin
- Decreases treatment discomfort
Lasers Applications in Medicine
bull Dermatology
ndash Vascular lesions
ndash Select Pigmented
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Laser Treatment of
Vascular Skin Lesions
Laser Treatment of Vasculature
bull Chromophore Oxyhemoglobin (blood)
bull Pulse Duration Variable (1-10 milliseconds)
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Problem Nonspecific epidermal (melanin) absorption
Answer Epidermal Cooling
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Cooling the Superficial Skin Layers
Target
Chromophores
Epidermal
Melanin
Cooling Medium
Dermis
Epidermis Epidermis
Dermis
Prevents epidermal injury
Leaves the dermal target susceptible
to laser induced thermal injury
Cryogen Spray Cooling Device
Contact Cooling Devices
Air Cooling Device
Epidermal Cooling
- Allows the use of higher fluences
- Allows safe treatment of darker skin
- Decreases treatment discomfort
Lasers Applications in Medicine
bull Dermatology
ndash Vascular lesions
ndash Select Pigmented
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Laser Treatment of
Vascular Skin Lesions
Laser Treatment of Vasculature
bull Chromophore Oxyhemoglobin (blood)
bull Pulse Duration Variable (1-10 milliseconds)
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Chromophores in human skin - absorption spectra
of hemoglobin melanin and water
Ru
by
Nd
YA
G
514
532 694 1064
Arg
on
KT
P
Pu
lse
d
Dye
Ale
xa
nd
rite
755
Ca
rbo
n
dio
xid
e
10600
Wavelength (nm)
500 1000 3000
Hemoglobin
Melanin Water
5000 10000 E
rY
AG
2940 577
595
Cooling the Superficial Skin Layers
Target
Chromophores
Epidermal
Melanin
Cooling Medium
Dermis
Epidermis Epidermis
Dermis
Prevents epidermal injury
Leaves the dermal target susceptible
to laser induced thermal injury
Cryogen Spray Cooling Device
Contact Cooling Devices
Air Cooling Device
Epidermal Cooling
- Allows the use of higher fluences
- Allows safe treatment of darker skin
- Decreases treatment discomfort
Lasers Applications in Medicine
bull Dermatology
ndash Vascular lesions
ndash Select Pigmented
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Laser Treatment of
Vascular Skin Lesions
Laser Treatment of Vasculature
bull Chromophore Oxyhemoglobin (blood)
bull Pulse Duration Variable (1-10 milliseconds)
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Cooling the Superficial Skin Layers
Target
Chromophores
Epidermal
Melanin
Cooling Medium
Dermis
Epidermis Epidermis
Dermis
Prevents epidermal injury
Leaves the dermal target susceptible
to laser induced thermal injury
Cryogen Spray Cooling Device
Contact Cooling Devices
Air Cooling Device
Epidermal Cooling
- Allows the use of higher fluences
- Allows safe treatment of darker skin
- Decreases treatment discomfort
Lasers Applications in Medicine
bull Dermatology
ndash Vascular lesions
ndash Select Pigmented
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Laser Treatment of
Vascular Skin Lesions
Laser Treatment of Vasculature
bull Chromophore Oxyhemoglobin (blood)
bull Pulse Duration Variable (1-10 milliseconds)
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Cryogen Spray Cooling Device
Contact Cooling Devices
Air Cooling Device
Epidermal Cooling
- Allows the use of higher fluences
- Allows safe treatment of darker skin
- Decreases treatment discomfort
Lasers Applications in Medicine
bull Dermatology
ndash Vascular lesions
ndash Select Pigmented
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Laser Treatment of
Vascular Skin Lesions
Laser Treatment of Vasculature
bull Chromophore Oxyhemoglobin (blood)
bull Pulse Duration Variable (1-10 milliseconds)
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Contact Cooling Devices
Air Cooling Device
Epidermal Cooling
- Allows the use of higher fluences
- Allows safe treatment of darker skin
- Decreases treatment discomfort
Lasers Applications in Medicine
bull Dermatology
ndash Vascular lesions
ndash Select Pigmented
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Laser Treatment of
Vascular Skin Lesions
Laser Treatment of Vasculature
bull Chromophore Oxyhemoglobin (blood)
bull Pulse Duration Variable (1-10 milliseconds)
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Air Cooling Device
Epidermal Cooling
- Allows the use of higher fluences
- Allows safe treatment of darker skin
- Decreases treatment discomfort
Lasers Applications in Medicine
bull Dermatology
ndash Vascular lesions
ndash Select Pigmented
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Laser Treatment of
Vascular Skin Lesions
Laser Treatment of Vasculature
bull Chromophore Oxyhemoglobin (blood)
bull Pulse Duration Variable (1-10 milliseconds)
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Epidermal Cooling
- Allows the use of higher fluences
- Allows safe treatment of darker skin
- Decreases treatment discomfort
Lasers Applications in Medicine
bull Dermatology
ndash Vascular lesions
ndash Select Pigmented
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Laser Treatment of
Vascular Skin Lesions
Laser Treatment of Vasculature
bull Chromophore Oxyhemoglobin (blood)
bull Pulse Duration Variable (1-10 milliseconds)
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Lasers Applications in Medicine
bull Dermatology
ndash Vascular lesions
ndash Select Pigmented
Lesions
ndash Tattoos
ndash Laser Hair Removal
ndash Skin Resurfacing
ndash Skin Rejuvenation
ndash Acne
ndash Vitiligo
Laser Treatment of
Vascular Skin Lesions
Laser Treatment of Vasculature
bull Chromophore Oxyhemoglobin (blood)
bull Pulse Duration Variable (1-10 milliseconds)
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Laser Treatment of
Vascular Skin Lesions
Laser Treatment of Vasculature
bull Chromophore Oxyhemoglobin (blood)
bull Pulse Duration Variable (1-10 milliseconds)
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Laser Treatment of Vasculature
bull Chromophore Oxyhemoglobin (blood)
bull Pulse Duration Variable (1-10 milliseconds)
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Immediate blood vessel hemorrhage after
pulsed dye laser treatment in an animal model
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Laser Treatment of
Pigmented Lesions
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Laser Treatment of
Pigmented Lesions
bull Chromophore Melanin
bull Pulse Duration Very Short (Q-switched)
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Tattoo Removal
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Tattoo Removal
bull Target Chromophore Tattoo pigment
bull Pulse Duration Very Short (Q-switched)
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Zelickson BD Mehregan DA Zarrin AA et al Clinical Histologic
and Ultrastructural Evaluation of Tattoos Treated with Three Laser
Systems Lasers Surg Med 1994 364-372
bullPhotothermal and Photoacoustic
bullWavelength selection based on color
bullShock waves break up tattoo dye and
then blood cells clear away
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Laser Hair Removal
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Lasers for Hair Removal
Ruby Laser (l = 694 nm)
Alexandrite Laser (l = 755 nm)
Diode Laser (l = 800 nm)
Long Pulsed NdYAG Laser (l =1064 nm)
Pulsed Filtered Flashlamp (l = 590 - 1200 nm)
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Laser Hair Removal
bull Target Chromophore Hair Shaft Melanin
bull Pulse Duration Long ( 20-50
milliseconds)
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
J Am Acad Dermatol 2006 Sep55(3)402-7 Epub 2006 May 26
The effects of laser-mediated hair removal on immunohistochemical staining properties of hair follicles
Orringer JS Hammerberg C Lowe L Kang S Johnson TM Hamilton T Voorhees JJ Fisher GJ
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Laser Skin Resurfacing
bull CO2 and ErYAG lasers
bull Target tissue water
bull Tissue ablation
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Formation of New Collagen
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Ablative Non-ablative Fractional Photothermolysis
Manstein D Herron GS Sink RK Tanner H Anderson RR
Fractional photothermolysis a new concept for cutaneous
remodeling using microscopic patterns of thermal injury
Lasers Surg Med 200434(5)426-38
Methods to induce collagen remodeling
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
Photodynamic Therapy (PDT)
bull PDT is a drug-device
combination
bull The topical drug is
activated by appropriate
light
bull Requires
ndash Photosensitizer
ndash Light
ndash Oxygen
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
- ALA is applied topically to the skin and converts to
Protoporphyrin IX a naturally-occuring powerful
photosensitizer
- ALA is preferentially absorbed by fast-growing cells
eg AKrsquos sebaceous glands sun-damaged cells
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture
PDT
bull Photosensitizer is
applied to desired
treatment areas
bull Wait
bull Photosensitizer
washed off
bull Laser or light source
treatment
bull Photoprotection
Beckman Laser Institute
BLI
QuickTimetrade and aTIFF (Uncompressed) decompressor
are needed to see this picture