Monocular band optic atrophy.

Band or "bow tie" optic atrophy is characterized by well-described ophthalmoscopic findings in the optic nerve and nerve fiber layer and homonymous hemianopia. It is typically associated with compressive lesions of the pregeniculate postchiasmal visual pathway or, less commonly, congenital malformations affecting the postgeniculate radiations or cortex. A unique case with band optic atrophy is described because of the unilateral visual defect. The optic atrophy is strictly unilateral and without an obvious structural lesion that could explain the optic disc damage. However, incidental cerebral gray matter cortical heterotopia may mark a congenital insult that contributed to both of these abnormal findings.