trabeculectomy

Trabeculectomy is a surgical procedure used to lower intraocular pressure in glaucoma by creating a guarded channel that allows aqueous humor to drain from the anterior chamber into a subconjunctival bleb, thereby reducing IOP. The goal is to achieve sustained pressure reduction to protect the optic nerve when medical therapy or laser treatment is insufficient or poorly tolerated.

Indications include chronic open-angle glaucoma or angle-closure glaucoma that remains uncontrolled or progressive despite topical medications, laser therapy, or intolerance to medications. It may be performed alone or in combination with cataract extraction when both conditions are present. Alternatives include aqueous shunt implants or other filtering surgeries.

The operation is typically performed under local anesthesia with sedation or general anesthesia. A flap of conjunctiva and a partial-thickness scleral flap is created, the inner sclera is entered to form a controlled drainage path, and an iridectomy may be performed to prevent blockage. The scleral flap is sutured to regulate flow and the conjunctiva is closed to form a filtration bleb on the ocular surface. The result is a site where fluid filters from the eye, lowering intraocular pressure.

Adjuncts such as mitomycin C or 5-fluorouracil may be used in high-risk patients to reduce scarring and improve longevity of success. The procedure may be performed with fornix-based or limbus-based conjunctival incisions, and may be combined with cataract surgery.

Postoperative care includes topical antibiotics and anti-inflammatory drops, close monitoring of IOP, and potential needling or revision to optimize bleb function. Complications can include hypotony, bleb leak, infection, choroidal effusion, cataract progression, and bleb failure.