DR. SHWETA PARAKH

DR.SHRUTANJOY MOHAN DAS, DR. LUTHRA SAURABH, DR. SHREY MAHESHWARI

Abstract

An 8-year-old boy presented with diminution of vision OS since childhood. BCVA was 6/6 OD and 6/24 OS (-0.50 DC at 180deg OD, +5.50DS /-2.50DC@160deg OS). Anterior segment OD was normal. OS showed iris coloboma & absent ciliary zonules superotemporally. Disc and macula were normal OU. Atypical superotemporal peripheral chorioretinal coloboma with intact intercalary membrane was seen in OS.

Typical ocular coloboma occurs due to defective closure of inferior embryonic fissure between 6-7th week of intrauterine life. Atypical colobomas are outside inferonasal area and do not originate in a defect of embryonic fissure closure. Atypical coloboma involving superior quadrants of iris, retina & choroid is a rare anomaly with very few cases being reported in literature.They result from defective closure of superior ocular sulcus due to variation in genes encoding type 1 BMPR1A and TBX2.This case re-emphasizes the importance of peripheral retinal screening and wide-field imaging.