The Cup-to-disc Ratio Is Smaller in the Pseudotumor Cerebri Population Compared to Norms: Implications for Anterior Optic Neuropathies

A small cup:disc (C:D) ratio is a known "risk factor" for anterior ischemic optic neuropathy (AION), a disease characterized by disc edema. The small cup:disc ratio in AION may be related to the pathophysiology as a marker of a "crowded" optic nerve head with implications concerning blood supply. We hypothesized that an optic nerve with a small C:D ratio may bemore likely to swell from any cause, not just ischemia. We began to investigate this hypothesis by performing a chart review of pseudotumor cerebri (PTC) in order to discern if small C:D ratios were over-represented in this population.