Workup for Optic Atrophy

Optic nerve atrophy is a common neuro-ophthalmic problem. It represents the end result of either ascending degeneration after destruction of ganglion cells in the retina, or descending atrophy following destruction of nerve fibers in the optic nerve, chiasm, optic tract and sometimes the retrogeniculate visual pathways. It usually presents with optic nerve pallor that is typically (but not invariably) associated with decreased visual function. The key task in the evaluation is to determine whether there is an on-going process causing destruction of ganglion cells, as determining the cause may allow halting progression of vision loss, and sometimes even visual recovery. This chapter discusses how a careful neuro-ophthalmic history and exam can often establish an etiology or at least substantially narrow the differential diagnosis and guide further workup. OCT analysis can often clarify the clinical picture, and in addition may allow quantitative analysis over time. Of all diagnostic studies, neuroimaging (typically MRI with contrast) has by far the highest yield. Further testing should be performed in a directed fashion.