Ruby (F/29) a teacher, came for eye examination, vision with existing glasses is fine seeing far.. but she reported difficulty seeing student’s book placed on table opposite of her & having tired eyes with near work.
Vision without glasses
R: 6/18-
L: 6/18-
Vision with existing glasses of 2years
R: -1.25/-0.50×165 (6/6)
L: -1.25/-0.50×180 (6/6-)
Examination shows: (Delay Fogging)
R: -1.50 (6/6) [+1.00 blur lens test: 6/12]
L: -1.50 (6/6) [+1.00 blur lens test: 6/9-] (L: left dominant eye) L>R
Add: +0.75 R>L
Other assessments show:
Examination of Eye Alignment/Vergence (Cover Test, CT)
NMD @Distance
NMD @Near
(alternating CT: upon covering left eye, patient reported the target goes to her right. when covering right eye, the target goes to her 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 – 2 XP (blue part)
+1.00 Near: 4 – 6 XP (blue part)
-1.00 Near: 1 – 3 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
+2.00
(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)
MEM – Monocular Estimation Method (Accommodation lag – to measure accommodation response seeing near target)
R: +0.75
L: +0.75
(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: 30 YO, 30 YO, 30 YO
L: 30 YO, 30 YO, 30 YO
(normal value: AA goes according to age; YO=years old)
NPC (Convergence – ability of eye to maintain a single clear near image) by RAF rule
TTN, 5/7cm, TTN, 5/7cm, TTN, TTN
(normal value: Break/Recovery in less than 10cm or to the nose, TTN)
Accommodation Facility – ability to change focus: far to near or near to far (by Flipper +/-2.00)
BE: 9 cycle per minit(cpm), difficult with minus lens(2nd lens)
R: 10 cycle per minit(cpm), difficult with minus lens(2nd lens) [both eyes see better than with right eye]
L: 11 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)
Fusional Reserves (Convergent/Divergent reserve stamina) by Prism Bar
Near, Base-Out/Convergent, PFV: x/25/16
Near, Base-In/Divergent, NFV: 10/12/10
Distance, Base-In/Divergent, NFV: x/8/6
Distance, Base-Out/Convergent, PFV: x/25/16 (above break point 10, double then single)
(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: 2 cpm (double with Base Out)
Distance: 3 cpm (double with Base Out)
(normal value: 1 cycle = 2 times clearing target
Distance: 12-18 cpm
Near: 12-18 cpm)
Interpupillary distance, IPD = 6.2cm