The Causes of Optic Disc Edema in Patients Presenting With Significantly Compromised Vision.

Background: To evaluate the most common causes of optic disc edema (ODE) in patients with significantly compromised vision (initial best-corrected visual acuity [BCVA] of 20/400 or worse) at presentation.

Methods: Retrospective chart review over a 5-year period of consecutive patients presenting to tertiary neuro-ophthalmology clinics at the University of Toronto.

Results: A total of 656 patients with ODE were included, and 49 patients (7.47%) had an initial BCVA of 20/400 or worse. There were 54 eyes included at baseline and 49 eyes at final follow-up. There were 29 female and 20 male patients. The mean age at first visit across patients was 55.9 years. Female patients (n = 29) were significantly older than male patients (n = 20) ( P < 0.05). The causes of ODE were optic neuritis (ON) (n = 22; 40.7%), nonarteritic anterior ischemic optic neuropathy (NAION) (n = 22; 40.7%), arteritic anterior ischemic optic neuropathy (AAION) (n = 5; 9.26%), uveitis-related (n = 3; 5.56%), papilledema from idiopathic intracranial hypertension (IIH) (n = 1; 1.85%), and Vogt-Koyanagi-Harada disease (n = 1; 1.85%). Initial BCVA was not significantly different between ON and NAION groups ( P = 0.52); however, final BCVA was significantly better in the ON group ( P < 0.0001). The mean initial BCVA was worst in the AAION group (2.62 ± 0.54 logarithm of the minimum angle of resolution). The most common cause of ODE in patients <40 years old was ON (83.3%), whereas the 2 most common causes in patients >80 were NAION (60%) and AAION (40%). In patients between the ages of 60-80, NAION (100%) was the only cause.

Conclusions: Patients with ODE and poor vision at presentation represent a minority of cases seen in neuro-ophthalmology clinics (<10%). Optic neuritis and NAION are the 2 most common causes of ODE with poor vision at presentation. These findings are limited by a small sample size and potential sampling bias.