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CHAN YI YANG

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YYang C (M/22) came for eye examination, with complaint of sometimes slight blurry far vision with existing glasses of 1year. He has worn this power for 3-4years. No headache is reported. He reported playing basketball in his old glasses of power 500.

Vision without glasses
R: cannot guess 6/120
L: cannot guess 6/120

Existing glasses
R: -8.50/-0.25×10 (6/7.5-)
L: -7.75/-0.75×5 (6/7.5-)

Subjective Refraction
R: -8.75/-0.25×10 (6/6-) PHNI R>L
L: -8.25/-0.50×5 (6/6-) PHN
Near: L>R

Other assessments show:

Cover Test
Distance: small XP, fast recovery
Near: small – moderate XP, fast recovery
(RE shows bigger XP movement than LE)

Howell Card
Distance: 2 – 4 XP
Near: 6 – 8 – 10 XP (will drift higher XP without blink)
+1.00 Near: 12 – 14 XP
-1.00 Near: 4 – 6 XP
+2.00 Near: 14 XP
-2.00 Near: 0 – 2 XP

NRA 
+1.75

PRA 
-1.50

NPC
TTN, TTN, TTN, TTN, TTN, TTN
(we notice his eyes deviating out but he can bring back his eyes in with focus)

AA
R: 14.5D, 13.5D, 13.5D (clear with blink then blur the next moment)
L: 14.5D, 13.5D, 13.5D (clear with blink then blur the next moment)

Accommodation Facility (+/- 2.00) 
BE: 7 cpm, difficult minus lens
R: 10 cpm, difficult minus lens
L: 10 cpm, difficult minus lens

MEM
R: +1.00
L: +1.00

Fusional Reserves
Near, PFV: x/20/18
Near, NFV: x/20/18
Distance, PFV: x/25/18 (above break pt 16, double then single)
Distance, NFV: x/10/8
(pt reported seeing double but if he focuses, he can see single)

Vergence Facility
Near: 0 cpm (double BO, double did not get closer with blink)
Distance: 0 cpm (double BO, double did not get closer with blink)

Interpupillary distance, IPD = 6.0cm

YYang told us that he sometimes sees blurry watching TV, in which he needs to focus his eyes then it will be clear. When he relaxes, vision will be blurry. The same goes to his near vision, while using phone.. in which he will take a break after seeing blurry on phone.

We prescribe daily disposable contact lens for sports.

We prescribe Dot card to strengthen convergence, improving exophoric eye posture.

Notes

Vision without glasses
6/6 – smallest testing line
6/7.5 – 2nd smallest line
6/9 – 3rd smallest line
6/12 – 4th smallest line
6/15 – 5th
6/18 – 6th
6/21 – 7th
6/24 – 8th

Examination of Eye Alignment
Cover Test, CT @ Distance & Near
– NMD(No Movement Detected) or
– small XP, fast recovery
EP = Esophoria is misalignment of eye, eye is deviated inwards
XP = Exophoria is misalignment of eye, eye is deviated outwards
ACT: alternating CT

Examination of Eye Posture
(Howell Card) by 6^ BD OD
Distance:
– 0-3 XP (blue part) or
– 0-1 EP (yellow part)
Near:
– 0-6 XP (blue part)

Accommodation/Focusing analysis – ability to relax
NRA
+1.50 to +2.50

Accommodation/Focusing analysis – ability to focus
PRA
-1.37 to -3.37

Convergence, NPC – ability of eye to maintain a single clear near image (RAF rule)
Break/Recovery – within 10cm or TTN(to the nose)

AA(Amplitude Accommodation) – eye stamina (Dioptre, D) (RAF rule)
6yo – 16.5D | 6cm
9yo – 15.5D | 6.5cm
12yo – 14.5D | 7cm
15yo – 13.5D | 7.5cm
18yo – 12.5D | 8cm
21yo – 11.5D | 9cm
24yo – 10.5D | 10cm
27yo – 9.5D | 11cm
30yo – 8.5D | 12cm

MEM(Monocular Estimation Method) – measure accommodation response seeing near target
+0.25 to +0.75 (with movement)

Accommodation Facility – ability to change focus: far to near or near to far) by Flipper +/- 2.00
Monocular: 6cpm – 16cpm
Binocular: 4cpm – 14cpm
(1 cycle per minute, cpm = 2 words)

Fusional Reserves –
Convergent/Divergent reserve stamina (Prism Bar)
Blur/Break/Recovery
Children 7-12yo
Near, BO/PFV: x/15-31/10-22
Near, BI/NFV: x/7-17/3-11
Adult
Near, BO/PFV: x/10-28/7-21
Near, BI/NFV: x/7-19/5-15
Distance, BO/PFV: x/4-18/5-9
Distance, BI/NFV: x/4-10/2-6

Vergence Facility  – ability to make rapid repetitive vergence changes (Prism Flipper 12BO & 3BI)
Distance: 12-18 cpm
Near: 12-18 cpm)
(1 cycle = 2 times clearing target)

Random Dot 3S  – 3D Vision 
12.5″