CXiang (M/21) came for eye examination, vision with existing glasses of about 3years is fine seeing far & near. He wants to try contact lens for outings.
Vision without glasses
R: 6/30
L: 6/45-
Vision with existing glasses
R: -2.25/-0.50×180 (6/6)
L: -2.25/-1.50×20 (6/9-)
Examination shows: (Delay Fogging)
R: -2.25/-0.75×180 (6/6) [+1.00 blur lens test: 6/12] (R: right dominant eye) R>L
L: -2.50/-1.00×20 (6/6) [+1.00 blur lens test: 6/15-]
Lowering short-sightedness monocularly/binocularly is not favoured
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.. when covering right eye, the target goes down)
small XP, fast recovery @Near (XP movement LE > RE)
(alternating CT: upon covering left eye, patient reported the target goes to his left.. when covering right eye, the target goes to his right)
(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 – 2 XP (blue part)
Near: 4 XP (blue part)
+1.00 Near: 8 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
+0.75
(normal value: +1.50 to +2.50)
PRA (Accommodation analysis – ability to stimulate accommodation) by minus lens
-2.25
(normal value: -1.37 to -3.37)
NPC (Convergence – ability of eye to maintain a single clear near image) by RAF rule
left eye deviates @8cm
(normal value: Break/Recovery in less than 10cm or to the nose, TTN)
AA (Amplitude Accommodation/Focusing – eye stamina/ability of eye to focus & sustain seeing near clearly) by RAF rule
R: 25 YO, 30 YO, 30 YO (pt reported target is clear @end of RAF rule, vision is better with astigmatism -0.75DC compared to -0.50DC)
L: 30 YO, 35 YO, 38 YO (pt reported target is clear @end of RAF rule, vision is better with astigmatism)
(normal value: AA goes according to age; YO=years old)
Facility (Accommodation facility – ability to change focus: far to near or near to far) by Flipper +/- 2.00
BE: 8 cycle per minit(cpm), difficult with clear minus lens(2nd lens)
R: 5 cycle per minit(cpm), difficult with minus lens(2nd lens) (both eyes see better than with right eye)
L: 5 cycle per minit(cpm), difficult with minus lens(2nd 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: +0.50
(normal value: +0.25 to +0.75)
Fusional Reserves (Convergent/Divergent reserve stamina) by Prism Bar
Near, Base-Out/Convergent, PFV: x/4/2
Near, Base-In/Divergent, NFV: x/18/14
Distance, Base-Out/Convergent, PFV: x/20/14 (above break point 10, target is double then single)
Distance, Base-In/Divergent, NFV: x/6/4
(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: 5 cpm (double Base Out, blink3 eyes then single)
Distance: 0 cpm (double with Base Out)
(normal value: 1 cycle = 2 times clearing target
Distance: 12-18 cpm
Near: 12-18 cpm)
Interpupillary distance, IPD = 6.0cm
We ask CXiang whether or not he has blurry near vision sometimes, he said that his near vision is fine.
Prescribe daily disposable
R: -2.50 (R>L)
L: -2.50
VA OU 6/6-
Near: R>L