Abstract: Objective To investigate the etiologies of optic disc swelling among patients presenting to Department of Neuro-ophthalmology, Beijing Tongren Eye Center. Design Retrospective case series. Participants 195 cases with optic disc swelling presenting to the Department of Neuro-ophthalmology, Beijing Tongren Eye Center from January to December 2018. Methods The electronic medical records of 195 patients with optic disc swelling were analyzed retrospectively. The etiologies of optic disc swelling in all patients, different age groups, unilateral or bilateral optic disc swelling groups were analyzed. A comparative analysis was made on the top two etiologies of optic disc swelling. Main Outcome Measures Constituent ratio of etiology. Results Non-arteritic anterior ischemic optic neuropathy (NA-AION) is the most common cause of optic disc swelling (49.7%), followed by optic neuritis (16.4%) and papilledema (7.7%). The etiology of optic disc swelling was different in different age groups. The most common cause of optic disc edema was pseudopapilledema in the≤20 years group. NA-AION in the ＞20 but ≤50 years group and > 50 years group. NA-AION is the most common cause of unilateral optic disc swelling, and papilledema is the most common cause of bilateral optic disc swelling. Compared with optic neuritis group, the age is older, unilateral swelling is more common, visual field defect is more, and ocular pain is less in NA-AION group. Conclusion NA-AION is the most common cause of optic disc swelling in neuro-ophthalmology clinic, followed by optic neuritis. The age of onset and the side of eye (unilateral or bilateral) are helpful for us to discriminate the etiologies of optic disc swelling.

Key words: optic disc swelling, non-arteritic anterior ischemic optic neuropathy, optic neuritis, papilledema