Compressive Optic Neuropathy Due To A Suprasellar Arachnoid Cyst Presenting With Cupping and Lack Of Optic Disc Pallor

Cupping without optic disc pallor, although infrequent, may be the initial presentation of a compressive optic neuropathy. Histologically, the cupping in compressive optic neuropathy has been shown to correlate with axonal loss rather than glial atrophy as is typically seen in glaucoma.1,4 Our patient demonstrated normal retinal nerve fiber layer measurements, generally accepted as a measure of axonal integrity5 suggesting an alternate mechanism of optic disc cupping. This case report highlights the importance of visual field testing in the differentiation of glaucomatous versus non-glaucomatous optic neuropathies presenting with optic disc cupping alone.