Abstract
To study and compare the macular thickness and peripapillary nerve fibre layer thickness in children with anisometropic amblyopia with those having strabismic amblyopia. A prospective non- randomised case series study was carried out. In all 50 children between the ages of 5 and 16 were selected. The anisometropic amblyopia group had 38 children (24 boys and 14 girls) and the strabismic amblyopia group had 12 children (7 boys and 5 girls) In both the groups the peripapillary retinal nerve fibre layer (RNFL) thickness and macular thickness was measured using optical coherence tomography (OCT) The RNFL thickness and macular layer thickness of the amblyopic eye was measured and compared to the normal eye of the same subject which served as a control. It was found that the macular thickness of the amblyopic eye was greater than that in the normal eye in the anisometropic amblyopia group, 247.8947+/-34.3926 in amblyopic eye versus 222.2386+/-31.1919 in the normal eye a p value = 0.00106. The RNFL thickness too was greater in the amblyopic eye when compared to the normal eye in this group 113.4060 +/-34.8319 versus 109.4494 +/- 29.0185, p value = 0.5922 thus not reaching statistical significance. In the strabismic amblyopia group however it was found that though the macular thickness was increased in the amblyopic eye it did not reach statistical significance, mean macular thickness (in microns) 233.75 +/-31.5224 in amblyopic eye versus 223.00+/- 31.4266 in normal eye a p value = 0.4118. and surprisingly the RNFL layer thickness was actually lesser than that in normal eyes in this group, 116.86 +/- 48.2924 versus 117.7089 +/- 37.2872 in normal eyes. P value = 0.9261. Thus this study found that macular thickness was raised in both anisometropic as well as strabismic amblyopia but RNFL thickness was not.
Keywords: OCT (optical coherence tomography) Strabismic amblyopia, anisometropic amblyopia, macular thickness, RNFL (retinal nerve fibre layer) thickness.
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Corresponding Author
Dr Arkendu Chatterjee
MS(Oph); DO; MBBS, Assistant Professor, Dept. Of Ophthalmology, NRS Medical College and Hospital, 138 AJC Bose Road Kolkata 700014