Bilateral optic nerve aplasia with corpus callosum hypogenesis in an otherwise healthy child: Report of a rare case.

Optic nerve (ON) aplasia is a rare congenital anomaly. It is characterised by the absence of optic nerve, nerve fibre layer, ganglion cells, and retinal blood vessels. ON aplasia is usually unilateral. Bilateral cases are very rare. We report such a rare case with bilateral ON aplasia and corpus callosum hypogenesis. An 11-month-old male child presented with a history of not seeing or following objects since birth. On examination, the child had microcornea and the absence of an optic disc in both the eyes. In addition, the right eye showed partial aniridia and few rudimentary retinal vessels in the posterior pole, while the left eye showed a chorioretinal coloboma but no evidence of any retinal blood vessels. Flash visual evoked potential was nonrecordable in both the eyes. MRI brain and orbit showed congenital aplasia of the ON on both sides with poorly developed optic chiasm, optic tract, and lateral geniculate body along with the features of corpus callosum hypogenesis. Child had no other systemic or endocrinological abnormalities.