Ivan (M/10) lost his glasses since a few months ago. His father said he tends to remove glasses to see near & to hold very upclose when seeing near.
Vision without glasses
R: 6/24
L: 6/24-
Examination shows:
R: -0.50/-1.50×5 (6/7.5), N5@33cm
L: -0.75/-1.50×180 (6/7.5), N5@33cm (L: dominant left eye)
Other assessments show:
Examination of 3D Vision (Random Dot 3S)
12.5″
(normal value: 12.5″)
Examination of Eye Alignment/Vergence (Cover Test)
NMD @Distance
moderate XP, fast 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
7cm, 7cm, 7cm
(normal value: less than 7.5cm)
AA (Accommodation/Focusing – eye stamina/ability of eye to focus & sustain seeing near clearly) by RAF rule
R: 9cm, 10cm, 10cm
L: 9cm, 10cm, 10cm
(normal value: less than 7.5cm for a 10yo)
NRA (accommodation analysis – ability to relax accommodation)
+1.50
(normal value: +1.50 to +2.50)
PRA (accommodation analysis – ability to stimulate accommodation)
-1.25
(normal value: -1.37 to -3.37)
Examination of Eye Alignment (Howell Card)
Distance: 0
Near: 10 XP
+1.00 Near: 12 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
Since Ivan has not worn glasses for a few months, he will wear his glasses fulltime to regulate his visual system back. Sometimes, when you do not correct your power or you did not wear your glasses for a period of time, you tend to stress your eyes in doing the extra work (by right, glasses should help to do some of the work). Your convergence and/or accommodation may go haywire too in trying to keep your vision clear during extensive near work especially having significant astigmatism like Ivan.
Therefore, you are advised to wear your glasses as prescribed by your eye care practitioner – to put your eyes at the most relaxed state. So, we will see Ivan in 2-3months to reassess his vergence & accommodation after his visual system is stabilised back upon fulltime wear of his glasses.
- Why do your child remove shortsighted glasses to see near?
- shortsighted power may be too strong that he/she finds removing glasses to see near is more comfortable
- accommodation/focusing may not be sufficient to sustain seeing near comfortably (supply x= demand)
- incorrect power of glasses
- binocular vision related
#tb