Two stage insertion of glaucoma drainage implants
Severe cases of secondary glaucoma can be treated by an implant consisting of a silicone tube attached to a circular plate. The open end of the tube is inserted into the anterior chamber and the plate is placed on the posterior sclera where it induces the formation of a large unilocular bleb. The complications associated with drainage of terminal eyes, namely hypotony, blockage of the drainage channel, and bleb inflammation followed by fibrosis are greatly reduced by inserting implants in 2 stages. The results of 34 operations are reported in which the implants were placed subconjunctivally but insertion of the tube into the anterior chamber was delayed until a fibrous layer had formed a bleb cavity around the episcleral plate. Early fibrosis of the bleb was controlled by a combination of anti-inflammatory agents. Thirty-two out of 34 cases followed for up to 3 yr drained well.