3. • 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
4.
5. 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 Cycloplegics
WET:- With Cycloplegics
DYNAMIC:- With Accomodation
6. • 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.
7. OPTICS OF RETINOSCOPY
ILLUMINATION
STAGE
REFLEX
STAGE
PROJECTION
STAGE
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
8.
9. Advantages of streak -
Undilated pupil
More accurate
Astigmatism
Axis of the astigmatism
D GOOD OLD
DAYZZ
DR.SHASHI
14. 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
16. WHAT TO ASSES?
Size, Speed &
Brilliance
Small (Narrow)
Fast &
Brighter
Low Refractive Error
Large (Wide)
Slow & Dim
(Faint Glow)
High Refractive Error
Hazy Media
18. 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.
19. (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)
20. 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
21. 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
22. W
E
T
R
E
T
I
N
s
c
P
Y
<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
TIMEES
1DROP 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
DROP
AFTER 40 MINS -do-
EFFECT 10-20DAYS
48-72 HRS 6-18 HRS 4-6 HRS -do-
0.5%,1%
2%
1%1%
24. PROBLEMS CAUSE SOULTION
RED REFLEX NOT VISIBLE
1.SMALL PUPIL
2.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
25. Uneven wavefront (aKA“optical aberrations”) can be because of aspherical
corneal, lens & retina or uneven thickness of tear film
27. 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
28. SUBJECTIVE REFRACTION
1. Subjective verification of refraction
By Trial & Error technqiue
Astigmatic Dial technique
2. Subjective refinement of refraction
JCC
Astigmatic Fan test
29. • 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
30.
31. 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.
33. 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
• ykush@yahoo.co.in./drdhir2014@gmail.com
HAND OF
GOD
