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Difficult Driving At Night?

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Mr Chong TW (M/49) came for eye examination.. with complaint of blurry seeing far & glaring when driving at night, glaring is worse with headlight of the vehicles coming from opposite side. Daytime driving is fine, but sometimes he realises that the car number plate will be blurry too.. those of few cars away. He has not worn any glasses before.

Vision without glasses
R: 6/6
L: 6/6- slow

Subjective Refraction
R: PL/-0.50×80 (6/6) (+1.00 blur lens test: 6/12)
L: PL/-0.50×90 (6/6) (+1.00 blur lens test: 6/7.5)
Add: +1.25
No hyperopia/long-sightedness is accepted mono & bino @far

R: PL/-0.50×80
L: PL/-0.50×90

Other assessments show:

Cover Test
Distance: NMD
Near: small XP, fast recovery

Howell Card
Distance: 0 – 1 EP
Near: 6 – 8 XP
-1.00 Near: 0 – 2 XP



16/24cm, 16/24cm, 16/24cm, 16/24cm, 16/24cm

NPC (with Add +1.75)
14/20cm, 14/20cm, 14/20cm

R: 46 YO, 46 YO, 46 YO
L: 46 YO, 46 YO, 46 YO

R: PL/-0.50×80
L: PL/-0.50×90
Add: +1.50

Fusional Reserves
Near, PFV: x/14/12
Near, NFV: x/14/10
Distance, NFV: x/6/4
Distance, PFV: x/14/12 (above break pt 10, double then 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)
Pt reported seeing the diplopic images.. one higher than the other (pt’s left image is seen going up) before slowly becoming paralel

Worth 4 Dots
Distance: 4 dots

Slit Lamp
R: very mild cataract
L: very mild cataract

R: -ve staining
L: -ve staining

Interpupillary distance, IPD = 6.8cm


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
– 0-3 XP (blue part) or
– 0-1 EP (yellow part)
– 0-6 XP (blue part)

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

Accommodation/Focusing analysis – ability to focus
-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)
Children 7-12yo
Near, PFV: x/15-31/10-22
Near, NFV: x/7-17/3-11
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