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Presentor:-Dr.Pushkar Dhir
Moderator :-Dr. Jyoti Puri
RETINOSCOPY
OPD -EXPERIENCE
• Far Point (FP) is the farthest point at which objects can be seen clearly by the eye.
• So in this patient d farthest point came out to be approx .4 mtrs.
• i.e she can see all d things vch r <4metres.
• To avoid this arbitrary n cumbersome method of finding refractive power ---> illumination reflexes were studeid in emmetropic and eye n correlated with the refraction power.
• Power= Diopteric power – cycloplegic – 1/working distance
ASTIGMATIC FAN
OBJECTIVE(what is done by the clinician)
SUBJECTIVE(refininng obj.refractn to maximize VA)
AUTO.REF
DUOCHROME TEST
ABERROMETRYKERATOMETRYRETINOSCOPY
REFRACTION
BINOCULAR BALANCING
JCC
DRY :- Without CycloplegicsWET:- With CycloplegicsDYNAMIC:- With Accomodation
• Started by Bownman in 1859
• Also known as:- Shadow test Skiascopy Pupilloscopy Korescopy
• The only way to assess the refractive error in infants, small children, illiterates, uncooperative patients with speech loss patients who speak a different language.
•Introduced quantitative refraction test.•Made possible to measure exact amount of refractive error using lenses. •Termed retinoscopie.
OPTICS OF RETINOSCOPY
ILLUMINATIONSTAGE
REFLEX STAGE
PROJECTIONSTAGE
Fundal area illuminated by the light reflected into the
patient’s eye .
Illuminated area serves as an OBJECT
Lights Rays reflected back from Fundus -> form reflex
shadow in pupillary area
Pupillary shadow observed by the examinar by aligning
his/her eyes
Advantages of streak -Undilated pupilMore accurateAstigmatism Axis of the astigmatism
D GOOD OLD DAYZZ
DR.SHASHI
APHAKIA- DULL GLOW
HIGH MYOPIA- STREAK NOT VISIBLE
VIDEO(on u tube)
TYPES OF RETINOSCOPES
Lister Reflecting Retinoscope
Priestley Smith ReflectingRetinoscope
Self Illuminating Retinoscope
Spot RetinoscopeStreak retinoscope
• Time to charge ur laptop
Done in long, darkened room, to aid in relaxation of accommodation The patient is made to sit at a distance of 1mt from the examiner Working distance of 2/3 mt is more convenient. Light is thrown in the patient’s eye who is instructed to look at a far point (to relax accomodation) If a cycloplegic used (wet retinoscopy) patient can look directly into the light & refraction
assessed along the actual visual axis. Observe a red reflex in the pupillary area of the patient. Retinoscope is moved in the horizontal and vertical meridia, keeping a watch on the red reflex
which also moves when the retinoscope is moved.
~ 50 cms
Movement(with working distance at 1 metre)
Against
Myopia >1D
With
Emmetropia
Hypermetropia
Myopia
<1D
No movement
Myopia =1D
WHAT TO ASSES?
Size, Speed & Brilliance
Small (Narrow) Fast & Brighter
Low Refractive Error
Large (Wide) Slow & Dim (Faint Glow)
High Refractive Error
Hazy Media
DEMONSTARTIONhttp://www.eyedocs.co.uk/ophthalmology-learning/articles/optics-and-refraction/1508-retinoscopy-simulator
Neutralization of red reflex :
in Streak Retinoscope
a. Neutralization - the band of red reflex moves ‘with’
or ‘against’ the movement of the band of light from retinoscope
- in simple spherical errors, at neutralization the band shaped reflex disappears and pupil appears completely illuminated.
Finding the cylindrical
axis
i) - break in alignment is observed when the streak is not parallel to one of the principal meridia(horizontal and
vertical).
- the axis, can be determined by rotating the streak until the
break disappears.
(ii) - width of the streak varies as it is rotated around the correct axis. It appears narrowest when the streak aligns with the true axis.
(iii)- Intensity of reflex is brighter when streak aligns with true axis.(iv)- Skewing (oblique motion of the streak reflex)
f. End point of neutralization - width of reflex widens progressively as the
neutralization is achieved, and at the end point, streak disappears and the pupil appears completely illuminated or completely dark
WET RETINOSCOPY : CYCLOPLEGICS In Retinoscopy
• Paralysis of Accomodation + Dilation of Pupil.
• Used in young children and hypermetropes where it is suspected that the accommodation is abnormally active and hinders exact retinoscopy.
• Mydriatics to be used cautiously in adults with shallow anterior chamber
WET RETINsc
PY
<5 yrs 5-8 yrs 8-20 yrs MYDRIATIC >CYCLOPLEGIC -do-
DOSE- TDS X 3DAYS
1DROP X 10 MIN X6 TIMES
1 DROP X 15 MIN X 6
TIMEES1DROP X15MIN
X3 TIMES -do-
PEAK EFFECT
2/3 DAYS 60-90MINS 80-90 MINS 20-40 MINS -do-
RETINO TIME- 4TH DAY
AFTER 90 MIN OF 1ST
DROP
AFTER 90 MIN OF 1ST
DROPAFTER 40 MINS -do-
EFFECT DURTN
10-20DAYS 48-72 HRS 6-18 HRS 4-6 HRS -do-
PMT- AFTR 3 WKS
AFTER 3 DAYS
AFTER 3 DAYS
8 HOURS/NEXT DAY -do-
CORRECTION-
1D 0.5 D 0.75 D XXX XXX
0.5%,1%
2%
1%1%
Beta Kitne Der
Lagegi!!!
Reflex Hi
nahi dikh
raha
NEED DR LIKH KAR BHEJ
DETA HUN
PROBLEMS IN RETINOSCOPY
PROBLEMS CAUSE SOULTION
RED REFLEX NOT VISIBLE1.SMALL PUPIL2.HAZY MEDIA
3.APHAKIA/HIGH MYOPIA
1.TRY MYDRIATICS +CYCLOPLEGICS COMBINATION
2.REDUCE WORKING DISTANCE + BRIGHT SOURCE OF LIGHT
3.TRY LENSES OF HIGH POWER+/- 7D, IF STILL NOT ,GO HIGHER.
CHANGING RETINOSCOPIC FINDINGS
ACCOMODATION USED BY PATIENTS
FOGGING- -- PLACE A LENS SUCH THAT VISION BECOMES 6/60 &
THEN START NEUTRALISING.V R ACTUALLY TYRING D CILIARY
MUSCLES BY DOING DIS.
SCISSOR SHADOWS
MIXED ABERRATION E.G KERATOCONUS
OPT FOR ONE SLIT & ADD LENSES , SLOWLY SLIT BECOMES
EQUAL,THAT’S IT.(DIRTY REFRACTION)
POSITIVE SPHERICAL
ABERRATIONS
NEGATIVE SPHERICAL ABERRATION
Uneven wavefront (aKA“optical aberrations”) can be because of asphericalcorneal, lens & retina or uneven thickness of tear film
MEASURING OPTICAL ABERRATIONS
• Shack-Hartmann (SH) aberrometer measures wavefront objectivel
Subjective Refraction• Power of spherical and cylindrical
refraction refined based on patient response
• General rule: Maximum Plus for Maximum Visual Acuity.
• Duochrome test: Based on chromatic aberration; red is
focused more hyperopically than green; yellow is focused on retina
• Letters on both red and green background should appear equally clear
SUBJECTIVE REFRACTION
1. Subjective verification of refraction By Trial & Error technqiue Astigmatic Dial technique
2. Subjective refinement of refraction JCC Astigmatic Fan test
• Combination of two sphero-cylinders: -0.25D sphere & +0.50D cylinders with axes at right angles.
• Combination of two sphero-cylinders: -0.25D sphere & +0.50D cylinders with axes at right angles.
• To determine end-point of magnitude, place JCC with axis parallel to the axis of the cylindrical prescription.
Jacksons Cross Cylinder
Astigmatic Dial Technique
• Fog the eye
• Patient asked to look & identify darkest &sharpest line in astigmatic dial.
• Add minus cylinder of progressively increasing power
• Axis perpendicular to the darkest & sharpest line, till all lines are clear.
• Revert back fogging.
REFERENCES• http://www.slideshare.net/meikocat/Refraction• http://www.eyedocs.co.uk/ophthalmology-learning/articles/opti
cs-and-refraction/1508-retinoscopy-simulator• http://retinoscopy.blogspot.in/
• http://books.google.co.in/books?id=6I6JeDWonhQC&pg=PA2&lpg=PA2&dq=RETINOSCOPY+WITH+PLANE+MIRROR&source=bl&ots=owV9UpZtAO&sig=ku6SiYptvYp_qlEbBi-g2YW7izM&hl=en&sa=X&ei=-mypU8K5MdeUuASBi4HIDw&ved=0CEkQ6AEwCg#v=onepage&q=RETINOSCOPY%20WITH%20PLANE%20MIRROR&f=false
• http://www.college-optometrists.org/en/college/museyeum/online_exhibitions/optical_instruments/retinoscopes.cfm
Had dat Referee had 6/6 refined vision , Argentina would never hav won 1986 FIFA WORLD CUP!!!!!
• THANK YOU EVERYONE FOR PATIENTLY LISTENING TO THIS SEMINAR.
• For feedbacks & brickbats plz mail at• [email protected]./[email protected]
HAND OF GOD