Drainage Devices In Treatment Of Glaucoma

Abstract

Glaucoma is the second leading cause of blindness, is characterized by changes in the optic disc and visual field defects. The elevated intraocular pressure was considered the prime factor responsible for the glaucomatous optic neuropathy involving death of retinal ganglion cells and their axons. Glaucoma, a leading cause of irreversible visual loss, is characterized by loss of retinal ganglion cells (RGC) and their axons over a period of many years. Glaucomatous optic neuropathy is characterized by changes in the optic disc and visual field defects. Glaucoma is a heterogeneous group of diseases and the pathophysiology of glaucoma is believed to be multifactorial. Multiple factors acting either on cell bodies or their axons are believed to lead to RGC death. According to various theories, factors like elevated intraocular pressure (IOP) and vascular dysregulation primarily contribute to the initial insult during glaucomatous atrophy., the end result in glaucomatous eyes is the dysfunction and death of RGCs leading to irreversible visual loss. Other than the conventional treatment which is surgery and drugs lowering the IOP, there is a line of treatment for the refractory glaucoma that does not respond to such treatment,ie.The Glaucoma Drainage Devices(GDD). Glaucoma drainage devices are designed to divert aqueous humor from the anterior chamber to an external reservoir, where a fibrous capsule forms about 4-6 weeks after surgery and regulates flow. These devices have shown success in controlling intraocular pressure (IOP) in eyes with previously failed trabeculectomy and in eyes with insufficient conjunctiva because of scarring from prior surgical procedures or injuries. They also have demonstrated success in complicated glaucomas, such as uveitic glaucoma, neovascular glaucoma, and pediatric and developmental glaucomas, among others. Since the introduction of the first glaucoma drainage device, Molteno implant. Current GDDs can be classified into those with resistance, those with no resistance, and those with variable resistance to aqueous outflow. GDDs with resistance include,Ahmed Glaucoma Valve and -Krupin eye implant 11