Qling (F/12) complains of blurry far vision looking at whiteboard at school with existing glasses.
Vision with existing power since 6YO (Cycloplegic Refraction, power after put eye drop at eye specialist clinic)
R: +0.75/-4.00X10 (6/7.5)
L: PL/-2.75X170 (6/45+)
Examination shows:
R: +0.25/-4.00X10 (6/6) N5@35cm
L: -1.50/-3.00X170 (6/9) PHNI, N5@35cm
Other assessments show:
3D Vision (Random Dot 3S)
100″
(normal value: 12.5″)
Examination of Eye Alignment/Vergence (Cover Test)
NMD @Distance
small XP fast recovery @Near
(normal value: orthophoria/NMD-No Movement Detected or small XP small 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 (Howell Card)
Distance: 0 -> 2 XP
Near: 4 -> 6 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
NPC (Convergence – ability of eye to maintain a single clear near image) by RAF rule
6cm, 6cm, 8cm, 12cm, 15cm
(normal value: less than 7.5cm)
Qling has 150 of shortsighted power/myopia in left eye while her astigmatism is maintained. When we see power increment in one eye only, we will ask about the posture and to reinforce proper posture. Her vision in left eye is blurred for quite some time, so her 3D vision seems reduced. We can appreciate the perception of 3D only when both eyes can see a target clearly at the same time. Having uncorrected power in one eye and/or both eyes or lazy eye/amblyopia or even strabismus/crossed eye or other underlying eye condition, our 3D vision will be disrupted. We will assess her vision again after 4-6weeks of full-time spectacle wear to see whether or not her vision improves.
Her convergence gives receded result upon repeated testing. This may tell us that: she sees fine at first, but after a while, the ability of eye to maintain single clear image is reduced so she may see blurry near vision sometimes especially after looking at near for a long time. However, due to non-optimum power in left eye for quite some time, we will let her wear new power & assess her Convergence again after 4-6weeks full-time wear of new power.