Glaucoma Surgery

Glaucoma is a disease in which the optic nerve is damaged, leading to progressive and irreversible loss of vision. Glaucoma can develop at any intraocular pressure (IOP), but elevated intraocular pressure is one of the major risk factors for the development and progression of glaucoma. Most treatments for glaucoma are targeted at lowering the intraocular pressure, either by decreasing the formation of aqueous fluid in the eye, or, as in the case of glaucoma filtration surgery, by increasing the outflow of fluid from the eye. Trabeculectomy is a filtering surgery where an ostium is created into the anterior chamber from underneath a partial thickness scleral flap to allow for aqueous flow out of the eye. The aqueous flows into the subconjunctival space, usually leading to an elevation of the conjunctiva, referred to as a filtering bleb . There are several suggested routes for the aqueous after reaching the filtering bleb. These routes include filtration through the conjunctiva into the tear film, absorption by vascular or perivascular conjunctival tissue, flow through lymphatic vessels near the margins of the surgical area, and drainage through aqueous veins . Trabeculectomy is performed for treatment of glaucoma inadequately controlled by maximally tolerated medical therapy.