Topiramate-induced bilateral secondary angle closure and myopia shift

Abstract

A 41-year-old female with a history of migraine had no previous ocular problems except myopia with spherical refraction of −2.25 D OD and −1.75 D OS. She experienced sudden onset of bilateral blurred vision, ocular fullness sensation, and headache after undergoing topiramate therapy for 7 days (50 mg/day). Her visual acuities with the presenting glasses were 20/200 OD and 20/50 OS. Intraocular pressures (IOPs) were 44 mmHg OD and 49 mmHg OS, respectively. Autorefraction measurement showed spherical refraction of −5.25 D OD and −4.75 D OS. Best-corrected visual acuities were 20/20 for both oculus dexter (OD) and oculus sinister (OS). Slit-lamp examination revealed bilateral conjunctival chemosis, very shallow anterior chambers, forward displacement of lens–iris diaphragm, round and sluggishly reacting pupils, and closed angles on gonioscopy. A B-scan ultrasound displayed choroidal thickening in both eyes. An ultrasound biomicroscopy demonstrated bilateral 360° ciliochoroidal effusions with forward rotation of ciliary body but no pupillary block. Impression of topiramate-induced bilateral angle-closure glaucoma and acute myopic shift was recorded. She was advised to discontinue topiramate immediately and was administered antiglaucoma medication and mydriatics. Two days later, IOP returned to normal limits and myopic shift resolved after 1 week. Her visual acuity with previous glasses improved to 20/20 OU. In addition, choroidal effusions also subsided gradually. The presented case highlights the possible side effects of topiramate, offers management and suggestion for such a condition, and brings awareness to sulfa drug complications.