The Leading Causes of Optic Disc Edema Seen in Tertiary Care, Academic Neuro-Ophthalmology Clinics

Abstract

Background: Optic disc edema (ODE) is one of the most common reasons for referral to a neuro-ophthalmologist. There are various causes that require vastly different workup. Thus, differentiating among each cause is important. Our goal was to determine the causes of ODE and various clinical characteristics of consecutive patients with ODE presenting to neuro-ophthalmology clinics. Methods: A retrospective review of consecutive patients with ODE over a period of 5 years were included. Fundus photographs were routinely obtained as part of clinical care. Clinical data including retinal nerve fiber layer thickness, best-corrected visual acuity, and visual field mean deviation were retrieved, and patients were grouped by etiology. Results: A total of 654 patients (n = 462 or 70.6% women and 192 or 29.4% men) with ODE were included with a mean age of 41.2 ± 17.9 years. Female patients were significantly younger than male patients (mean age female participants: 38.7 years, male participants: 47.6; P < 0.001). The top 5 most common causes of ODE in our clinics were idiopathic intracranial hypertension (IIH; 351/654 or 53.7%), nonarteritic anterior ischemic optic neuropathy (NAION; 116/654 or 17.4%), non-IIH papilledema (71/654 or 10.9%), optic neuritis (ON; 46/654 or 7.0%), and uveitis (17/654 or 2.6%). When considering female-only patients, the top 3 causes of ODE were IIH, non-IIH papilledema, and NAION. Among male-only patients, the top 3 causes were NAION, IIH, and non-IIH. Among the top 5 causes of ODE, visual acuity was the worst at presentation in the ON group and the best in the patients with IIH. The Humphrey mean deviation was the worst in ON/NAION groups and best in IIH group. The ODE was most severe in patients with non-IIH papilledema and least severe in ON group. Non-IIH patients with papilledema were not significantly different in visual acuity and visual field parameters at presentation compared with patients with IIH papilledema. Patients with papilledema (both IIH and non-IIH etiologies) had significantly better visual function at presentation compared with other top causes of disc edema (P < 0.001). Conclusions: The most common cause of ODE seen in neuro-ophthalmology clinics was IIH, and these patients were more likely to present with preserved visual function. The higher prevalence of IIH was likely why most patients with ODE were women. Visual function at presentation was not able to differentiate the specific cause of papilledema; however, it was an important differentiating factor for all papilledema cases compared with all other causes of ODE including ON and NAION.