John (M/24) came for eye examination, vision with existing glasses of 1/2 year is fine seeing far & near but he reported blurry far vision sometimes. His frame was broken.
Vision without glasses
R: 6/24
L: 6/30+2
Vision with existing glasses
R: -1.75/-0.50×125 (6/6)
L: -2.00/-0.50×15 (6/6)
Examination shows: (Delay Fogging)
R: -1.75/-0.50×125 (6/6) [+1.00 blur lens test: 6/12+]
L: -2.00/-0.50×15 (6/6) [+1.00 blur lens test: 6/7.5-] (L: left dominant eye) L>R (adding +0.50 in left eye R>L)
Add is not favoured (L>R)
Lowering -050 or -025 shortsightedness/astigmatism monocularly/binocularly is uncomfortable @far & near
Other assessments show:
Examination of Eye Alignment/Vergence (Cover Test, CT)
NMD @Distance
small EP, fast recovery @Near
(alternating CT: upon covering left eye, patient reported the target goes to his right.. when covering right eye, the target goes to his left)
(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: 0 – 1 EP (yellow part)
+1.00 Near: 2 – 4 XP (blue part)
-1.00 Near: 3 – 5 EP (yellow 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
-0.50
(normal value: -1.37 to -3.37)
NPC (Convergence – ability of eye to maintain a single clear near image) by RAF rule
7/9cm, 7/9cm, 7/9cm, 7/9cm, 7/9cm, 8/10cm
(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: 21 YO, 25 YO, 25 YO (pt reported target is blurry @end of RAF rule, only comes into focus starting @30cm, 28cm, 28cm)(astigmatism is omitted as vision is reported to be better without)
L: 25 YO, 26 YO, 26 YO
(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 +/- 1.50
BE: 4 cycle per minit(cpm), cannot clear minus lens(2nd lens) [with Flipper +/-2.00]
R: 12 cycle per minit(cpm), difficult with minus lens(2nd lens) (both eyes see better than with right eye)
L: 12 cycle per minit(cpm), difficult with minus lens(2nd lens) (both eyes see better than with left eye)
– cannot clear -2.00
(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: +1.00
L: +1.00
(normal value: +0.25 to +0.75)
Fusional Reserves (Convergent/Divergent reserve stamina) by Prism Bar
Near, Base-In/Divergent, NFV: 12/16/14
Near, Base-Out/Convergent, PFV: 16/20/18
Distance, Base-In/Divergent, NFV: 8/10/8
Distance, Base-Out/Convergent, PFV: 8/14/12
(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: 10 cpm (double Base Out, blink then single swiftly)
Distance: 0 cpm (double Base Out)
(normal value: 1 cycle = 2 times clearing target
Distance: 12-18 cpm
Near: 12-18 cpm)
Interpupillary distance, IPD = 6.3cm
We asked John if he has blurry near vision sometimes, he said his near vision is fine.
We plan on prescribing him flipper eye exercise when he comes back soon.