Jev (M/14) came for eye examination, with complaint of sometimes blurry near vision after long hours of online learning with existing glasses of 2+ years. The spectacles are not aligned for quite some time and the lens coating has peeled off & scratched.
Vision without existing glasses
R: -3.00 (6/12-)
L: -3.75 (6/7.5+)
Examination shows:
R: -3.50/-0.75×20 (6/6) (R: dominant right eye)
L: -3.50/-0.25×180 (6/7.5+) PHNI
Relax Add: +1.00
Other assessments show:
Examination of 3D Vision (Random Dot 3S)
20″
(normal value: 12.5″
Examination of Eye Alignment/Posture (Cover Test)
NMD @Distance
small XP, fast then moderate recovery @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
NPC (Convergence – ability of eye to maintain a single clear near image) by RAF rule
6cm, 8cm, 10cm
(normal value: less than 10cm or to the nose, TTN)
AA (Accommodation/Focusing – eye stamina/ability of eye to focus & sustain seeing near clearly) by RAF rule
R: 8cm, 8cm, 8cm
L: 8cm, 8cm, 8cm
(normal value: 8cm for 14yo)
Examination of Eye Alignment/Posture (Howell Card)
Distance: 2 XP
Near: 8 XP
+1.00 Near: 2 XP
+0.50 Near: 8 XP
(normal value: 1 EP-0 or 0-3 XP @Distance & 0-6 XP @Near)
EP = Esophoria is misalignment of the eye, eye is deviated inwards
XP = Exophoria is misalignment of the eye, eye is deviated outwards
Examination of Fusional Reserves (Convergent/Divergent reserve stamina) by Prism Bar
Near, Base-Out/Convergent, PFV: 14/12
Near, Base-In/Divergent, NFV: 12/10
(normal value: Break/Recovery)
Near, PFV: 15-31/10-22
Near, NFV: 7-17/3-11
[Scheiman et al, 1989]
Jev has some 8 exophoria at near alignment/posture. In order to have comfortable near vision, he should have at least twice in reserve stamina of 16 to balance the near posture.. but he only has 14 in this finding (Near, Base-Out/Convergent, PFV: 14/12). This is decompensated exophoria at near – after some time of looking at near, when he has exhausted his reserve stamina, he may start to see blurriness. We give a little help of Relax power in near, his near posture surprisingly is normalised to 2 exophoria.
His convergence, NPC is receded – this tells us that as he keeps looking at near, his ability (to maintain a single clear image) deteriorates with time. Also, his Convergent reserve stamina, PFV is not sufficient to fuel & support his near posture. We will prescribe home vision therapy(VT) pencil push up in order to strengthen his convergence & to normalise his PFV.
It is no good to wear misaligned glasses. Should the glasses need some adjustment, bring to your eye care practitioner & we will have them serviced & adjusted for you. When you purchase your glasses, lenses are cut & positioned at the centre of your eyes for clearest, comfortable vision. Looking though the off-centre part of lens will bring about unnecessary eyestrain to your eyes.
Lens coating is sensitive to chemical.. using body/hair shampoo to wash glasses is a big no no. When the lens coating is compromised, peeling may occur. We should use spectacles lens cleaner/lens wipes to clean your lenses.