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Delayed-Onset Giant Bleb Formation and Persistent Intraocular Pressure Elevation in a Patient With COVID-19 and a Long-Term Ahmed Glaucoma Valve

Sun E, Iwach AG, Lin SC

The American journal of case reports, 2026

Abstract

BACKGROUND Glaucoma is a progressive optic neuropathy often associated with elevated intraocular pressure (IOP). Implantation of an Ahmed glaucoma valve (AGV), a silicone or polypropylene shunt tube, can regulate aqueous humor drainage through a filtering bleb and lower IOP. A rare postoperative complication of AGV implantation is giant bleb formation, which typically occurs early in the postoperative period and can require surgical revision if IOP becomes uncontrolled or if the bleb causes discomfort/cosmetic concerns. We describe a case of bilateral refractory steroid-induced glaucoma and delayed-onset giant bleb formation after AGV implantation, temporally associated with coronavirus disease 2019 (COVID-19). CASE REPORT A 39-year-old man with bilateral steroid-induced glaucoma presented for an unscheduled visit 3 years after AGV implantation in the left eye with complaints of photophobia and foreign body sensation. He also reported recent COVID-19 onset. Tonometry revealed elevated IOP in the left eye (50 mm Hg). Examination showed an enlarged superotemporal bleb overlying the Ahmed valve plate. Treatment comprising topical glaucoma medications and oral acetazolamide improved bleb appearance and stabilized IOP within 3 months. At the last follow-up, the patient remained stable, with well-controlled IOP in both eyes on 4 topical glaucoma agents (6 medications total) and oral acetazolamide. CONCLUSIONS This report describes delayed-onset giant bleb formation and pronounced…

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