Prospective study into the effect of an intraocular injection of a steroid in the prevention of Glaucoma drainage surgery failure after cataract surgery

Trabeculectomy surgery for Glaucoma establishes a connection between the inside of the eye and the subconjunctival space which lies just below the surface of the eye. Flow of fluid through this connection forms a subconjunctival blister known as a bleb. Aqueous humor (fluid inside the front of the eye )is absorbed from the bleb into the blood stream. A significant casue of failure of trabeculectomy is scarring of the bleb. If the bleb develops an excessive amount of scar tissue then fluid is prevented from exiting and the eye pressure is increased. Cataract surgery has been shown in research trials to increase the risk of trabeculectomy failure. Control of postoperative scar formation after cataract surgery is a significant challenge in the surgical management of glaucoma in patients who have had previous Trabeculectomy surgery. Current practice is to use topical steroids and antiscarring agents such as 5-fluorouracil (5-FU). Although the use of 5-FU is widespread, scar tissue remains a problem in many patients and treatment is associated with side effects including wound leaks and disruption of the ocular surface. Active scarring is associated with inflammation. Triamcinolone is a synthetic corticosteroid that inhibits the inflammatory process and may therefore reduce scar formation. Injection of triamcinolone into the vitreous jelly of the eye has been widely used as a treatment for various diabetic and inflammatory conditions which are unresponsive to topical corticosteroids. It has been used as a mono-therapy and co-therapy for various back of eye conditions, and is also indicated for visualisation during vitrectomy.