CYee (F/42) came for eye examination, with complaint of blurry far vision especially in right eye recently. She has a pair of glasses that she uses for night driving only (she did not bring along, power is reported to be -1.25 & -0.75).
Vision without glasses
R: 6/45+
L: 6/7.5-
Examination shows: (Delay Fogging)
R: -2.00/-0.25×180 (6/6) [+1.00 blur lens test: 6/12-] (R: right dominant eye) R>L
L: -0.50/-0.25×20 (6/6) [+1.00 blur lens test: 6/9-]
Add: +1.00
She prefers -1.75 in right eye to feel more comfortable binocularly.
Other assessments show:
Examination of Eye Alignment/Vergence (Cover Test, CT)
NMD @Distance
NMD @Near
(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: 2 – 4 XP (blue part)
No Add Near: 0 – 2 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
+1.00
(normal value: +1.50 to +2.50)
PRA (Accommodation analysis – ability to stimulate accommodation) by minus lens
-0.75
(normal value: -1.37 to -3.37)
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)
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)
AA (Amplitude Accommodation/Focusing – eye stamina/ability of eye to focus & sustain seeing near clearly) by RAF rule
R: 35 YO, 35 YO, 35 YO
L: 35 YO, 35 YO, 35 YO
(normal value: AA goes according to age; YO=years old)
Fusional Reserves (Convergent/Divergent reserve stamina) by Prism Bar
Near, Base-Out/Convergent, PFV: x/25/20
Near, Base-In/Divergent, NFV: x/20/18
Distance, Base-In/Divergent, NFV: x/12/8
Distance, Base-Out/Convergent, PFV: x/25/20
(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: 12 cpm
Distance: 11 cpm
(normal value: 1 cycle = 2 times clearing target
Distance: 12-18 cpm
Near: 12-18 cpm)
Prescribe
R: -1.75/-0.25×180
L: -0.50/-0.25×20
Add: +0.75 (for desktop use)
All near tests are done with Add.
Interpupillary distance, IPD = 6.5cm