Optic nerve hypoplasia is an important developmental anomaly of the retina and optic nerve that may occur more frequently than now appreciated. It occurs with equal frequency in males and females and as a unilateral or bilateral defect. It usually produces marked visual impairment and becomes symptomatic early in life as a heterotropia when unilateral and as the cause of grossly poor vision when bilateral. Examination of the fundus reveals a small disc of abnormal character often surrounded by a halo. Histologic examination of similarly affected eyes suggests a primary failure of differentiation of ganglion cells. The etiology of this anomaly remains unknown. Its clinical recognition is an important ophthalmic diagnosis.
Walton DS, Robb RM. Optic Nerve HypoplasiaA Report of 20 Cases. Arch Ophthalmol. 1970;84(5):572-578. doi:10.1001/archopht.1970.00990040574003