A rare case of type 3 usher syndrome with bilateral cystoid macular edema treated with topical dorzolamide

Abstract

A 30-year-old female presented with gradually progressive diminution of vision for 1 month, with night blindness for the past 5 years and difficulty in hearing for the past 10 years. Her developmental history and family history were unremarkable. Ocular examination revealed visual acuity of 6/36 in both eyes. Fundus showed features of retinitis pigmentosa with bilateral macular edema. Audiometry revealed bilateral sensorineural hearing loss; although, her vestibular functions were preserved. Clinical diagnosis of Usher syndrome type 3 was made based on normal hearing at birth, delayed presentation of progressive visual and auditory impairment with normal vestibular function, and developmental milestones. Her macular edema resolved after 3 months of treatment with topical dorzolamide therapy. The unique feature of this case is the presence of bilateral macular edema in type 3 Usher syndrome, which is rarely reported in literature.