Natural History of Nonarteritic Anterior Ischemic Optic Neuropathy

Visual acuity and quantitative perimetry (Octopus Program 32) testing was performed in the acute (3 months after onset) phases of disease in 27 patients with untreated NAION. Initial group mean acuity and sensitivity loss were compared to final values using the t test. Proportions of patients demonstrating a change of >2 lines acuity or >2 dB mean sensitivity were calculated. Patients were classified as either “progressive” (n = 6) or “stable” (n = 21) for purposes of additional subgroup analysis. There was no significant change in group mean visual acuity or field over time. Overall, significant worsening occurred in 11.1% for visual acuity and 22.2% for visual field; improvement occurred in 23.8% for acuity and 24.0% for field. Of 21 “stable” patients, none worsened for acuity and 4.7% showed late worsening of field; 31.3% showed significant improvement for acuity and 31.6% for field. No “progressive” patients demonstrated worsening or improvement after the initial progressive phase.