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EMILY TAN YAN

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13/6/2022

Emily Yan (F/15) non spectacles wearer, came for eye examination, teacher has asked her to go for eye examination. Her vision is fine seeing far & near. No headache is reported. But vision in her left eye is very blurry & she was told that she has power 200 in left eye a few years back.

Vision without glasses
R: 6/6-, N5@40cm
L: 6/60-, N8+@40cm

Examination shows:
R: -0.25 (6/6) [+1.00 blur lens test: 6/9+] (adding +1.00 in right eye still R>L)
L: -3.75 (6/6) [+1.00 blur lens test: 6/15-] (L: left dominant eye) R>L (adding +1.00 in right eye still R>L)
Near: R>L

Modified for comfort
R: -0.25
L: -2.25

Other assessments show:

Examination of Eye Alignment/Vergence (Cover Test, CT)
NMD @Distance 
(alternating CT: upon covering left eye, patient reported the target goes up & bigger.. when covering right eye, the target goes down & smaller)
small XP, fast recovery @Near (XP movement in right eye only, left eye no movement)
(alternating CT: patient reported no movement
(normal value: orthophoria/NMD-No Movement Detected or small XP, fast recovery)
EP = Esophoria is misalignment of the eye, eye is deviated inwards
XP = Exophoria is misalignment of the eye, eye is deviated outwards

Examination of Eye Alignment/Posture (Howell Card) by 6^ Base Down on Right eye
Distance: 0 – 1 EP (yellow part)
Near: 4 – 6 – 8 XP (blue part)
+1.00 Near: 6 – 8 – 10 XP (blue part)
-1.00 Near: 2 – 4 XP (blue part)
(normal value: 0-1 EP (yellow part) or 0-3 XP (blue part) @Distance; and 0-6 XP (blue part) @Near)
EP = Esophoria is misalignment of the eye, eye is deviated inwards
XP = Exophoria is misalignment of the eye, eye is deviated outwards

NRA (Accommodation analysis – ability to relax accommodation) by plus lens
+2.00
(normal value: +1.50 to +2.50)

PRA (Accommodation analysis – ability to stimulate accommodation) by minus lens 
-2.00
(normal value: -1.37 to -3.37)

NPC (Convergence – ability of eye to maintain a single clear near image) by RAF rule
TTN, TTN, TTN, TTN, TTN, TTN
(normal value: Break/Recovery in less than 10cm or to the nose, TTN)

Facility (Accommodation facility – ability to change focus: far to near or near to far) by Flipper +/- 2.00
BE: 5 cycle per minit(cpm), difficult with plus(1st lens) & minus lens(2nd lens)
[with plus lens, she sees blurry longer before clear & with minus lens, she sees blurry, but clear faster]
R: 10 cycle per minit(cpm), difficult with plus lens(1st lens) (both eyes see better than with right eye)
L: 9 cycle per minit(cpm), difficult with plus lens(1st lens) (both eyes see better than with left eye)
(normal value: 1 cycle = 2 words read
Monocular or R/L: 6cpm to 16cpm
Binocular or BE-both eyes: 4cpm to 14cpm)

MEM – Monocular Estimation Method (Accommodation lag – to measure accommodation response seeing near target)
R: +0.50
L: -1.25 (dim reflex)
(normal value: +0.25 to +0.75) 

AA (Amplitude Accommodation/Focusing – eye stamina/ability of eye to focus & sustain seeing near clearly) by RAF rule
R: 15 YO, 20 YO, 20 YO
L: 8 YO, 8 YO, 8 YO (given L: -2.75 for clearer near vision seeing target on RAF rule)
(normal value: AA goes according to age; YO=years old) 

Fusional Reserves (Convergent/Divergent reserve stamina) by Prism Bar
Near, Base-In/Divergent, NFV: x/2/-1

Fusional Reserves (Convergent/Divergent reserve stamina) by Prism Bar (with L: -2.75)
Near, Base-In/Divergent, NFV: x/4/2

Fusional Reserves (Convergent/Divergent reserve stamina) by Prism Bar (with L: -3.25)
Near, Base-Out/Convergent, PFV: x/12/10
Near, Base-In/Divergent, NFV: x/12/10
Distance, Base-In/Divergent, NFV: x/8/6
Distance, Base-Out/Convergent, PFV: x/10/8
(normal value: Blur/Break/Recovery)
Near, PFV: 10-28/7-21
Near, NFV: 7-19/5-15
Distance, PFV: 4-18/5-9
Distance, NFV: 4-10/2-6
[Scheiman et al – Adult Data]

Vergence Facility – ability to make rapid repetitive vergence changes (by Prism Flipper of 12Base Out & 3Base In)
Near: 0 cpm (double Base Out – double images are very far apart)
Distance: 2 cpm (double Base Out – double images are very far apart but they get single faster & double Base In – double images are very near but they get single slower)
(normal value: 1 cycle = 2 times clearing target
Distance: 12-18 cpm
Near: 12-18 cpm)

Interpupillary distance, IPD = 5.8cm

Prescribe contact lens
R: PL
L: -3.25

We prescribe Emily daily disposable contact lens on left eye only.. for full-time wear.

We will see her in 1month.

*Updated

Emily came back for follow up. Vision with contact lens is fine seeing far & near.. she feels her left eye is tired with near work.

Vision without glasses
R: 6/6, N5
L: 6/120, N8

Existing power
R: PL (6/6) N5
L: -3.25 (6/6) N5

Other assessments show:

Random Dots 3S
20″

Schober Test
Distance: outer green circle is in red & green colour alternatingly, inner red cross as normal
Near: normal

Cover Test
Distance: NMD
Near: small XP, fast recovery (RE shows more XP movement than LE)

Howell Card
Distance: 0 – 1 EP
Near: 8 – 10 XP
+1.00 Near: 14 XP
-1.00 Near: 6 XP
+2.00 Near: 10 XP (scale is very blurry)
-2.00 Near: 2 XP

NRA 
+2.00

PRA 
-3.25

NPC
TTN, TTN, TTN, TTN, LE deviates @6cm

AA
R: 13.5D, 13.5D, 13.5D 
L: 14.5D, 14.5D, 14.5D

Accommodation Facility (+/- 1.50) 
BE: 11 cpm, difficult minus lens (cannot clear +2.00)

Accommodation Facility (+/- 2.00) 
R: 13 cpm, difficult plus lens
L: 12 cpm, difficult plus lens

MEM
R: +0.75
L: -0.25

Modified
R: PL
L: -2.75

Fusional Reserves
Near, PFV: x/12/6
Near, NFV: x/10/6
Distance, NFV: x/6/4
Distance, PFV: x/16/12

Modified
R: PL
L: -2.50

Fusional Reserves
Near, PFV: x/8/6
Near, NFV: x/10/8

Vergence Facility
Near: 12 cpm
Distance: 0 cpm (double BO, double did not get closer with blink)

Interpupillary distance, IPD = 5.8cm

Prescribe
R: PL
L: -2.75

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

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, PFV: x/15-31/10-22
Near, NFV: x/7-17/3-11
Adult
Near, PFV: x/10-28/7-21
Near, NFV: x/7-19/5-15
Distance, PFV: x/4-18/5-9
Distance, 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″