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Medicontur IOLs: Materials & Design
Main Characteristics
Page 2 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
Material
OpticDesign
BALANCED TECHNOLOGY FOR OPTIMAL IOLs
OPTICAL
PERFORMANCE
STABILITY IN THE
EYE
LOW PCO RATE
LONG TERM
MATERIAL
PERFORMANCE
REFRACTIVE
STABILITY
TECHNOLOGY
Page 3 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
MEDICONTUR IOL PORTFOLIO
Hydrophilic IOLs
(25% and 26% water content, clear & yellow)
• Advanced monofocal IOLs (aspheric – neutral
approach)
• Premium Toric
• Premium Multifocal
• Premium Multifocal-Toric
• SML & Add-On IOLs
Hydrophobic IOLs
(clear & yellow)
• Advanced monofocal aspheric IOLs
• Proprietary SEMTE material with the
highest ABBE number (58); Tg (4°C)
• On the market since 2009
Page 4 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
OPTIMAL IOL – BALANCED TECHNOLOGY
MATERIAL
• REFRACTIVE INDEX (RI)
• CHROMATIC ABERRATION (ABBE NUMBER)
• BLUE-LIGHT & UV FILTERs
• GLASS TRANSITION TEMPERATURE (Tg)
• GLISTENING
DESIGN
• SHARP EDGE (SE)
• HAPTIC/OPTIC DIAMETER / CHARACTERISTICs
OPTIC
• ABERRATIONs (SPHERICAL, COMA…)
• COD
• PRECISION
Page 5 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
Material
OpticDesign
OPTIMAL IOL – BALANCED TECHNOLOGY
Page 6 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
HYDROPHILIC
Material
Page 7 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
HYDROPHILIC BENZ 25 (USA)
• There are many hydrophilic IOL materials on the market
DIFFERENT MATERIALs
DIFFERENT TECHNOLOGIEs &
DIFFERENT QUALITY
Medicontur uses BENZ 25, USA (as well as Zeiss, Physiol….)
IMPORTANT!
Distillation of monomers before polymerisation
• Disadvantage: 10% of material loss
BUT
• Advantage: clean, safe material; less prone to opacification and calcification inside a lens
• other companies e.g. Contamac produce without distillation process
Page 8 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
EOEMA
36%
HEMA
64%
Mixing hydrophilic and hydrophobic monomers
25% water content after combination of the two monomers, to form a highly
biocompatible polymer
Medicontur foldable raw material : a combination of two monomers
HEMA, highly hydrophilic monomer
• Pure HEMA = 38% water content
• BIOCOMPATIBILITY
EOEMA, hydrophobic monomer
• Approximately 2% water content
• ELASTIC PROPERTIES
• SOFTNESS
HYDROPHILIC BENZ 25
Page 9 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
Apart from design, polimer chain length has a
proven effect against cell adhesion :
A long chain acts as a ʺmolecular eyelashʺ
to prevent cell adhesion and protein deposit
Our raw material : low adhesion for a low PCO rate
Anti-PCO behaviour
Hydrogel MMA 26%
MEDICONTUR HYDROPHILIC – BENZ 25
Page 10 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
• for FILTERING AS MUCH AS NECESSARY
for PRESERVING AS MUCH AS POSSIBLE
Medicontur natural yellow filter protects the macula against the wavelengths between
390nm and 460nm thus covering the most dangerous zone of « blue light » and
maintaining scotopic vision (over 460nm)
Bi-Flex M yellow filter
NATURAL YELLOW FILTER
Page 11 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
SUMMARY: MEDICONTUR HYDROPHILIC IOLs; MATERIAL - BENZ 25
MAIN CHARACTERISTICS
RI 46
ABBE NUMBER 58
BLUE LIGHT FILTER YES; 390-460nm (violett)
ASPHERICITY Neutral
OPTIC Biconvex; Aspheric;
Aberration free
ANGULATION 0°; posterior vaulting
SE 360°; 10um
MANUFACTURING PROCESS LATHE CUT
TECHNOLOGY POLISH FREE
Page 12 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
HYDROPHOBIC
Material
Page 13 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
Low Contact angle High
Good Adhesiveness Poor
Good Wettability Poor
High Solid Surface Free
Energy
Low
HYDROPHOBICITY & CONTACT ANGLE in NATURE
Page 14 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
SPNSO
Berkeley/USA
EMTE S E M T E
Soft Ethyl-Methyl-Tri-Ethylacrylate
• 2008 MEDICONTUR developed SEMTE as the 2nd generation of hydrophobic material
• 2010 – officially launched
• 1st implantation of IOLs – February 2010, Germany
www.assouline.info
SEMTE – MEDICONTUR DEVELOPMENT
Page 15 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
SEMTE = GLISTENING FREE
GLISTENING = fluid filled vacuoles that form within the matrix of the lens when exposed to an aqueous environment
Affects Visual Acuity and Contrast Sensitivity
Mechanism unclearRefractive Index (lower the better, aim: close to RI crystalline lens)
Manufacturing (Cast molded)
Non Compatible packaging
Differences between hydrophobic materialsGlistening
Acrysof
Hoya
No glistening reported: (all RI close to crystalline lens)Tecnis
Aurolab
Hanita (Benz Research)
Medicontur
Glistening in HB IOL (Alcon)
(Courtesy by Michael Assouline, MD, PhD)
Page 16 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
1,55 1,5451,54
1,52
1,49
1,47 1,47
1,43
Refractive index
REFRACTIVE INDEX AT DIFFERENT HYDROPHOBIC IOLs ON THE MARKET
Page 17 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
GLASS TRANSITION TEMPERATURE of the MATERIAL (Tg)
The mechanical parameters of hydrophobic IOLpolymers are dependent on the glasstransition temperature of the material
Tg: the temperature at which the polymertransforms from a rigid glassy polymer to aflexible compliant material
- room temperature for PMMA
- below room temperature (22° C) forhydrophobic material, ensuring easymanipulation such as flexing and rolling - atlower operating room (OR) temperatures, somehydrophobic acrylic materials with higher Tgvalues can behave as rigid materials, in whichcase folding and compressing are morechallenging
- Lower Tg, better manipulation/softer in OR
Page 18 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
= Uneven focusing of an optical system that causes
different wavelengths of light to have different focal points,
thus decreasing optical performance
Refractive index: nE = 1.46 (546 nm, 35 °C)ABBEBENZ25 = 58
CHROMATIC ABBERATION
Graphs shows association of RI & ABBE number
Page 19 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
2 Dpt
CHROMATIC ABBERATION
Page 20 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
ABBE NUMBER
How Do We Measure Chromatic Aberration?
The Abbe number is a measure of the material's dispersion (variation of refractive index with wavelength) in relation to the refractive index. Low dispersion (low chromatic aberration) materials have high values of V.
The higher the Abbe number the lower the chromatic aberration and the higher the retinal image Quality
.
Zhao H., Mainster M. JCRS. 2007 2. Negishi K, et al. Arch Ophthalmol 2001.
Ernst Abbe (1840–1905) the German physicist
Page 21 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
1.Zhao H., Mainster M. JCRS. 2007 2. Negishi K, et al. Arch Ophthalmol 2001.
HYDROPHOBIC MATERIALs & Its ABBE NUMBER
0
10
20
30
40
50
60
3742 43
47
55 57
Page 22 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
Alcon Crisalline lens Medicontur
2,212
1,72
Dioptric shift (colour components of white light)
Worsening Improvement
HYDROPHOBIC MATERIALS MAY IMPROVE OR WORSEN CHROMATIC
ABBERATION
Page 23 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
Chromatic aberration of the eye: to correct or not to correct?
Page 24 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
The results of our Optics Express paper suggest than an IOL that corrects both spherical
and chromatic aberrations by combining aspheric and diffractive elements may have the
potential to provide an improvement in the quality of vision in patients after cataract
surgery.
Proff. Pablo Artal is the founder and director of the Laboratorio de Optica at the University of Murcia.
Visual effect of the combined correction of spherical and longitudinal chromatic aberrations
Pablo Artal, Silvestre Manzanera, Patricia Piers, and Henk Weeber
Optics Express, Vol. 18, Issue 2, pp. 1637-1648 (2010) doi:10.1364/OE.18.001637
Page 25 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
„the correction of chromatic aberration can improve visual acuity“
Proff. Pablo Artal, the founder and director of the Laboratorio de Optica at the University of Murcia. .
Page 26 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
MEDICONTUR – SEMTE : AN INNOVATIVE HYDROPHOBIC MATERIAL
MAIN CHARACTERISTICs
RI 47
ABBE 57
BLUE LIGHT FILTER YES; 380-510 nm
ASPHERICITY Neutral
SE 360°; 10 um
Tg (lowest on the market) 4°C
Glistening Glistening Free
Manufacturing Process Cryolathing
Page 27 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
HYDROPHOBIC MATERIAL (SEMTE ) – STRENGHTs
Property of the material Clinical evidence
Reduced tackiness
Unfolding after implantation
(similar to HL IOLs)
Low Tg – 4°C
(lowest on the market)
Improved mechanical properties
(better manipulation during implantation)
Excellent pseudo-plasticity Quick centration
Perfect SE
Page 28 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
MAIN CHARACTERISTICs OF HYDROPHOBIC MATERIALs on the MARKET
IOL
manufacturer
Contact angle
with water
Packaging Glass Transition
Temperature (Tg)
Manufacturing
method
Water
content
RI ABBE
number
Alcon 72° Dry 14.0-15.5°C Molding
Page 29 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
Material
OpticDesign
OPTIMAL IOL – BALANCED TECHNOLOGY
Page 30 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
Design
“The most important element of a successful IOL is the lens design. IOL must fit properly so that
it is stable in the long term, with minimal potential for decentration. Additionally, IOL design is
a key factor in inhibiting PCO.”Richard L. Lindsrom, MD
OPTIMAL IOL – BALANCED TECHNOLOGY
MEDICONTUR Bi-FLEX PLATFORM
OPTIC: 6/13mm
DOUBLE-LOOP HAPTICs
Page 31 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com | Ma
de
by
TN
N
WHAT IS PERFECT SHARP EDGE?
„Intraocular lenses with a radius curvature of less than 10.0 microns appear to have good
PCO protection“
Mayank et al; JCRS; vol.34; 2008
Medicontur „Bi-Flex“ & all „Flex“ platforms
SE 10 microns
SHARP EDGE
Page 32 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
„Geometry of the lens with a square posterior optic edge is the most important factor. This feature should be
present in 360° around the optic, as the optic-haptic junction of single piece lenses may represent sites
where the edge barrier effect is absent“
Werner L., Biocompatibility of intraocular lens materials;
2008 Wolters Kluwer Health
Alcon Acrysof – „Achilles heel“ around haptic – the source of PCO
ME
DIC
ON
TU
R B
i-F
LE
XSQUARE EDGE MUST BE PRESENT AT 360°
Page 33 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
Comp 3
25 microns
Comp 2
60 microns
Comp 1
35 microns
Bi Flex 677ABY
10 microns
COMPARISON IN DIFFERENT IOLs in OPTIC-HAPTIC JUNCTION
Page 34 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
Comp 5 Comp 6Comp 4
No Square Edge at all
at
Optic-Haptic
Junctions
COMPARISON IN DIFFERENT IOLs in OPTIC-HAPTIC JUNCTION
Page 35 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
Measurement of radii of Square Edge (SE) at optic-haptic junction by Scanning Electron Microscopy. The IOLs with discontinuity of SE in optic-haptic junction are not included
The smallerthe radius,
The more effectivethe square edge effect
60
35
25 25 2520 10
*Comp = Competitor
SQUERE EDGE HAS NOT THE SAME MEANING AT DIFFERENT PRODUCERS
Page 36 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com | Ma
de
by
TN
N
Polishing free surface
• Maintaining perfect SE
• Hydrophilic intracapsular IOLs
Hydrophilic material
– more difficult to maintain SE of IOLs because
of the hydratation process during production
POLISH FREE technology
– significantly enhancing of SE of IOLs
– Preventing PCO development
POLISH FREE TECHNOLOGY
Page 37 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
The specific Bi-Flex closed-loop
haptic design offers adequate resistance
• to a shrinking capsular bag
• haptics that do not overlap
• excellent axial stability
• optimal filling up of the capsular bag
• unmatched centration and stability
90°
90°
B i-F LE X
Bi-Flex design in a rigid ring
91°contact angle with simulation of rigid capsular sac of 9.0 mm diameter.
Note the good contact (homogeneous) of the loops with the capsular equator for their entire length.
In total Bi-Flex has more than
180°contact angle
between its loops
and the capsular bag.
180° CONTACT BETWEEN THE LOOPS & CAPSULA
Page 38 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
Medicontur Bi-Flex Average contact angle: 88.8°
Competitor 1Average contact angle: 69°
Experimental simulator with a diameter of 9 mm
Competitor 2 Average contact angle: 64.4°
A unique & patented design
180° CONTACT BETWEEN THE LOOPS & CAPSULAR BAG EQUATOR
Page 39 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
Material
OpticDesign
OPTIMAL IOL – BALANCED TECHNOLOGY
Page 40 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
Optic
„Optical performance is critical. If the IOL does not provide the patient with a satisfactory optical
outcome, then the IOL fails from the start.“Louis D. Nichamin, MD
OPTIMAL IOL – BALANCED TECHNOLOGY
Page 41 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
An ABERRATION is a departure of an image-forming optical system from ideal behaviour
Chromatic aberration are caused by dispersion (the variation of index of refraction of a medium with wavelenght
• Longitidunal
• Lateral
Monochromatic aberration are caused by geometry (the shape of teh lens)
• Spherical aberration
• Coma
• Distortion
• Astigmatism
• Field curvature
ABERRATIONs
Page 42 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
SPHERICAL ABERRATION - BASICS
42
+ + + =
Vertical
tiltAstigmatism Horizontal
coma
Spherical
aberration
Superimposed
wavefront
Optical aberration when light rays travel through the edges of the lens,
and light rays do not intersect in one focal point
Positive, Negative aberration and Aberration-free lenses
Zernike polynomials are widely used in ophthalmology to characterize
wavefront aberrations. The most significant parameter is the Z(4,0) which
describes the spherical aberration. For example:
Page 43 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
Young eye:
• Negative spherical aberration of the young crystalline lens balances
• Positive spherical aberration of the cornea*
• Essentially zero spherical aberration at the age of 19**
With age:
Functional vision is reduced as the aging crystalline lens loses the ability to compensate for
corneal spherical aberration*
*Guirao A, et al. J Opt Soc Am A. 2000;17:1697-1702. **Holzer M. Presented at DOC, 2006.
-+ + +
The Young Lens Aberration in the Aging Lens
Not drawn to scale Not drawn to scale
SPHERICAL ABERRATION
Page 44 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
Positive spherical aberration
Aberration-free
Negative spherical aberration
One focal point
Several focal points
Several focal points
Human cornea: +0.27 SA
Medicontur’s IOLs
Competitors’ IOLs
Page 45 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
The avarege human cornea has +0.27 μm spherical aberration [1]
The human crystalline lens has a small negative spherical aberration [2]
With age, the positive aberration of the lens increases [3] - blurred vision, reduce contrast sensitivity
SPHERICAL ABERRATION - IN THE EYE
Page 46 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
COMPETITORS
IOLs Spherical aberration with a 6.0 mm pupil
Medicontur IOLs 0.00 μm Aberration-free
Bauch&Lomb / SofPort AO 0.00 μm Aberration-free
Rayner / C-felx, Superflex 0.00 μm Aberration-free
PhysIOL IOLs - 0.11 μm Negative SA
Alcon / AcrySof IQ - 0.20 μm Negative SA
Zeiss / Acri.Smart - 0.26 μm Negative SA
AMO / Tecnis - 0.27 μm Negative SA
Table: Spherical aberration of aspheric IOLs. [6]
Page 47 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
SA depends on pupil size: The wider the pupil the higher the SA (scotopic vision)[4]
Depth of focus:
- Reduction of aberrations may reduce depth of focus with aspheric IOLs[6]
- Difference in spherical aberrations of up to 20 µm does not produce a clinically
significant difference in depth of focus[5]
Depth of focus (DOF) is the distance in between the object can be moved
backward and forward and still appear acceptably sharp in an image. .
SPHERICAL ABERRATION - IN THE EYE
Page 48 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
NEUTRAL ASPHERICITY APPROACH
Without precise wavefront analysis the aberration of thecornea itself is unknown. So the implantation of an IOL
with a negative aberration can result in a drasticdecrease in depth of field.
Neutral approach, the aberration-free IOLs are the bestoptions in these cases.
Page 49 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
REFERENCES
[1] Distribution of corneal spherical aberration in a comprehensive ophthalmology practice and whether keratometry can
predict aberration values; George H.H. Beiko, BM, BCh, FRCS(C), Wolfgang Haigis, MS, PhD, Andreas Steinmueller, MS; J
Cataract Refract Surg 2007;33:848–858
[2] The spherical aberration of the crystalline lens of the human eye; George Smith, Michael J. Cox, Richard Calver, Leon F.
Garner; Vision Research 41 (2001) 235–243
[3] Aspheric IOLs can improve image quality for cataract surgery patients; Uday Devgan, MD, FACS; healio article
[4] C constant: New concept for ray tracing–assisted intraocular lens power calculation; Thomas Olsen, MD, PhD, Peter
Hoffmann, MD; J Cataract Refract Surg 2014; 40:764–773
[5] Fellow-eye comparison of 2 aspheric microincision intraocular lenses and effect of asphericity on visual
performance; Mayank A. Nanavaty, DO, MRCOphth, MRCS(Ed), David J. Spalton, FRCP, FRCS, FRCOphth, Kavita B. Gala,
DO; J Cataract Refract Surg 2012; 38:625–632
[6] Wavefront aberrations, depth of focus, and contrast sensitivity with aspheric and spherical intraocular lenses:
Fellow-eye study; Mayank A. Nanavaty, DO, MRCOphth, MRCSEd, David J. Spalton; Cataract Refract Surg 2009; 35:663–671
[7] Analysis of the possible benefits of aspheric intraocular lenses: Review of the literature; Robert Monte´s-Mico´ , OD,
MPhil, PhD, Teresa Ferrer-Blasco, OD, MSc, PhD, Alejandro Cervin˜ o, OD, PhD; J Cataract Refract Surg 2009; 35:172–181
Medicontur IOLs: Materials & Design
OBJECTIVE HANDLING
How to manage competition with confidence
Page 51 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
My doctor does not want to use hydrophilic IOLs since hydrophilic material is less stable
with often calcification/opacification
There are many hydrophilic IOL materials on the market
DIFFERENT MATERIALs
DIFFERENT TECHNOLOGIEs & DIFFERENT QUALITY
IMPORTANT!
Distillation of monomers before polymerisation is CRUTIAL for PURITY
• Disadvantage: 10% of material loss
BUT
• Advantage: clean, safe material; less prone to opacification and calcification
inside a lens
• other companies e.g. Contamac produce without distillation process
Page 52 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
LOOK AT THE TREND IN PREMIUM MULTIFOCAL IOLs:
2016 – DP AREA STATISTICs
PROOF: since year 1999 over 4.000.000 HL IOLs have been sold & implanted
52%48%
HB Multifocal
HL Multifocal
Medicontur uses the same HL material - BENZ 25 (USA);
as well as Zeiss & Physiol.
HIGH STANDARDS FOR PRODUCTION AT MEDICONTUR
SAFE and HIGH QUALITY HL IOLs are appreciated by surgeons
DO NOT FORGET:
HL material = BETTER UVEAL BIOCOMPATIBILITY
Page 53 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
My doctor does not want to use hydrophilic IOLs since hydrophilic IOLs have higher PCO rate
than HB
Statistically PCO occurs sooner and more often in hydrophilic IOLs. But based on many
studies PCO depends on rather design than the material.
PCO rate finally makes a difference in outcomes and patient satisfaction – especially
important in case of multifocal IOLs. The best optical offer will suffer from capsular fibrosis
Yag laser: the later the better
“ Additionally, IOL design is a key factor in inhibiting PCO.”Richard L. Lindsrom, MD
Page 54 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
Recent work has shown that the IOL should have a crisp square edge to be effective and electron microscope
shows that although IOLs are sold with a square edge profile there is in fact a great deal of difference in
edge quality between companies. It is relatively easy to get a crisp edge oh hydrophobic polymers but
more difficult with the hydrophilic materials used by many smaller companies. This is because
hydrophilic materials are machined in a dehydrated state and then rehydrated for clinical use. In this
process the lenses lose some of their edge quality. This explains why hydrophilic IOLs tend to get more PCO.
Another factor of relevance is that, ideally the IOL should have a 360° SE and unfortunately many IOLs have a
breach in the edge where optic and haptics meet, causing the so called “Achilles heel” effect in the barrier.
.
Spalton D:Latest Development in intraocular lenses. 09/10 CET; p. 28
The higher incidence of PCO with hydrophilic materials may also be due to the fact that the optic edge with
hydrophilic materials is not as sharp as with hydrophobic materials.
Nanavaty MA, Spalton DJ, Boyce J, et al. Edge profile of commercially available
square-edged intraocular lenses. J Cataract Refract Surg.2008;34(4):677-686.
DESIGN (SE) rather than material is crucial for protection of PCO development
Page 55 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
Prospective study; 25 patients; the Medicontur 677 AB IOL in one eye (hydrophilic), and the 877
AB IOL in the contralateral eye (hydrophobic). The two lenses share the same design and sharp
posterior edge.
Follow up to 30 months
Results:
Visual acuity and refraction did not vary between IOLs. Posterior capsule opacification was
very low in this series, and slightly worse for the hydrophobic model. To-date, 3 eyes with
the hydrophilic model and 2 eyes with the hydrophobic model underwent laser posterior
capsulotomy.
Clinical proof: Bellucci et al.: ESCRS 2014: Same design hydrophobic and hydrophilic
intraocular lenses: intra-individual comparison
Page 56 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
Clinical proof: WESCR 2014:Helena Gerbec: First results with
Medicontur Bi-flex 677AB hydrophilic aspheric IOL
Retrospective review of 856 eyes of 642 patients
Follow-up: 33 months:
Indications for YAG capsulotomy:
BCVA =/< 0,7 and PCO (Health Insurance Institute of Slovenia standard) or
BCVA reduction by >20% and PCO
RESULTS:
PCO and YAG capsulotomy: 9 eyes (5 patients) - 1%
Page 57 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
1. Dexl et al.: ESCRS 2014:Visual Outcome, Patient Satisfaction and Spectacle Independency after Implantation of
Progressive Bi-Flex M. Final Result of a Multicentric study.
2. AF Dunai, K Kranitz, E Juhasz, G Sandor, T Filkorn, ZZs Nagy. Comparison of two multifocal IOL types – short and
medium-term visual outcomes
3. Gyori J.: Long term functional and morphological outcomes and patient satisfaction after cataract surgery with Bi-Flex M
implantation with / without posterior central circular capsulorhexis (PCCC).
4. A. Bachenger, T.Rückl, W.Riha, G. Grabner, A.Dexl: Rotational stability and visual outcome after implantation of a new
toric intraocular lens for the correction of corneal astigmatism during cataract surgery. J Cataract Surgery 2013:
Clinical proof: 1. Bi- Flex-M (HL): 150 consecutive patients (=300 eyes)
1 year follow up; YAG = 0
2. Bi-Flex T (HL): 30 eyes; 1 year follow-up; YAG =0
Page 58 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
Medicontur „Flex“ platform
SE 10 microns
My doctor tells that SE is not a issue today, since all companies today
have SE
YES, it is true. Almost all companies claim their IOLs have sharp edge.
BUT
WHAT IS PERFECT SHARP EDGE?
„Intraocular lenses with a radius curvature of less than 10.0 microns appear to have good
PCO protection“
Mayank et al; JCRS; vol.34; 2008
Page 59 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
Alcon Acrysof – „Achilles heel“ around haptic – the source of
PCO
ME
DIC
ON
TU
R B
i-F
LE
XSQUARE EDGE MUST BE PRESENT AT 360°
„Geometry of the lens with a square posterior optic edge is the most important factor. This feature should be
present in 360° around the optic, as the optic-haptic junction of single piece lenses may represent sites
where the edge barrier effect is absent“
Werner L., Biocompatibility of intraocular lens materials;
2008 Wolters Kluwer Health
Page 60 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
DO ALL COMPANIES HAVE REAL & PERFECT SE?
NO
Recent work has shown that the IOL should have a crisp square edge to be effective and electron
microscope shows that although IOLs are sold with a square edge profile there is in fact a great deal of
difference in edge quality between companies
Nanavaty MA, Spalton DJ, Boyce J, et al. Edge profile of commercially available square-edged intraocular lenses. J Cataract Refract Surg.,
2008;34(4):677-686.
Spalton D:Latest Development in intraocular lenses. 09/10 CET; p. 28
Page 61 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
Comp 3
25 microns
Comp 2
60 microns
Comp 1
35 microns
Bi Flex 677ABY
10 microns
CLINICAL PROOF:COMPARISON IN DIFFERENT IOLs in OPTIC-
HAPTIC JUNCTION
Page 62 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
Comp 5 Comp 6Comp 4
No Square Edge at all
at
Optic-Haptic
Junctions
CLINICAL PROOF:COMPARISON IN DIFFERENT IOLs in OPTIC-
HAPTIC JUNCTION
Page 63 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
Measurement of radii of Square Edge (SE) at optic-haptic junction by Scanning Electron Microscopy. The IOLs with discontinuity of SE in optic-haptic junction are not included
The smallerthe radius,
The more effectivethe square edge effect
60
35
25 25 2520 10
*Comp = Competitor
CLINICAL PROOF: SHARP EDGE HAS NOT THE SAME MEANING AT
DIFFERENT COMPETITORs
Page 64 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
My doctor tells that PCO is not a problem since it can be easily treated by
Nd: YAG laser capsulotomy
Yes, it is true,
BUT
YAG capsulotomy may lead to other complications, including a short-term increase
in intraocular pressure, ocular inflammation, cystoid macular edema, and retinal
detachment. Besides, Nd:YAG laser capsulotomy does not improve visualization of
the peripheral retina, increases the overall costs for cataract treatment, and is not
available in large parts of the developing world.
Page 65 | March 2017 | Medicontur | Vision of Expertise | www.medicontur.com |
Clinical proofs: IATROGENICITY OF Nd:YAG CAPSULOTOMY HAS
BEEN DESCRIBED IN CLINICAL OBSERVATIONs
REFRACTION7% of eyes experienced a significant change in subjective refraction
Effect of Nd:YAG laser capsulotomy on refraction in multifocal apodized diffractive pseudophakia. Vrijman
V.:JRefract Surg. 2012 Aug;28(8):545-50. doi: 10.3928/1081597X-20120723-03.
MACULAR CHANGESThirty eyes of 30 patients with posterior capsule opacification following phacoemulsification were enrolled
in the study. Patients were classified according to total energy used during Nd:YAG laser capsulotomy (⩽80 mJ = group I, > 80 mJ = group II).
RESULTS: In group I, IOP increased 1 week postoperatively (P = .007) and declined to preoperative
levels at 1 month. In group II, IOP increased 1 week postoperatively (P = .001) and did not return to
preoperative levels during 3 months of follow-up (P = .04). Both groups had increased macular
thickness compared to preoperative levels, but group II measurements were significantly higher 1 week
and 1 month postoperatively compared to group I (P = .004 and .03, respectively).
ARI S, Ophthalmic Surg Lasers Imaging. 2012 Sep: The Effects of Nd:YAG Laser Posterior Capsulotomy on Macular
Thickness, Intraocular Pressure, and Visual Acuity.
THANK YOU FOR NOTICING ALL DISCUSSED
FACTs