Risk Factors for Optic Disc Swelling in Acute Primary Angle Closure

Purpose: To investigate the risk factors for optic disc swelling in patients with acute angle-closure glaucoma (AACG).Methods: We analyzed 92 AACG patients and classified them into those with optic disc swelling (41 eyes) and those without it (control, 51 eyes). The time from symptom onset to presentation, intraocular pressure (IOP) before and after initial treatment, pupil dilation, ratio of the disc-to-fovea distance to the disc diameter, visual field parameters at 1 year, and retinal nerve fiber layer (RNFL) thickness at 3 months, 6 months, and 1 year after attack were evaluated.Results: In the swelling group, the IOP after medication was smaller compared to that before the initial treatment, whereas the pupil diameter was larger. The average cpRNFL thickness at 6 months and 1 year decreased compared to 1 month, correlating with the change in visual field parameters. Logistic regression analysis revealed that pupil diameter was a risk factor for optic disc swelling (hazard ratio: 1.161).Conclusions: Optic disc swelling is associated with decreased RNFL thickness and corresponding visual field defects at 6 months and 1 year. Clinical measures to prevent swelling in AACG patients are necessary. There is a high risk of optic disc swelling under severe pupillary block conditions. Further studies are needed to validate the risk factors for optic disc swelling.