Optic nerve aplasia: A case series.

Optic nerve aplasia (ONA) is a congenital optic nerve anomaly characterized by the absence of optic nerve head, retinal blood vessels, retinal ganglion cells, and optic nerve fibers in a malformed eye. Clinically, the condition presents with the absence of perception of light, afferent pupillary defect and a fundus appearance of absent optic nerve head, and retinal vessels with associated ocular and nonocular abnormalities. Systemic anomalies have been reported with bilateral ONA, whereas unilateral ONA is seen in otherwise healthy individuals. We report three cases of ONA with varied clinical presentations.