Bilateral optic nerve aplasia: a rare isolated central nervous system anomaly.

[aniridia]

Optic nerve (ON ) aplasia is a rare developmental anomaly comprising of absence of the ON , ganglion cells and the central retinal vessels . It is usually accompanied by a variety of central nervous system (CNS ) malformations . We report an extremely rare case of bilateral true ON aplasia occurring as an isolated CNS anomaly . A 10 -month -old female child was detected with bilateral absence of fixation , associated with multiple ocular findings of microcornea , anterior embryotoxon , pupillary corectopia , partial aniridia and lens coloboma . The optic disc locations were visible as avascular whitish areas . There were no retinal vessels seen in the disc area or elsewhere . There were bilateral multiple chorioretinal atrophic patches present . B-scan ultrasonography showed bilateral absence of ONs . Magnetic resonance imaging showed thinned out bilateral ONs with a hypoplastic optic chiasma and optic tract . There were no other CNS anomalies . Flash visually evoked potential was unrecordable .