Ahmed valve for elevated intraocular pressure associated with black diaphragm lenses for aniridia

PURPOSE. To evaluate the Ahmed valve for decrease elevated pressure associated with black diaphragm lenses for aniridia. METHODS. Drainage devices are useful to obtain good control of intraocular pressure in patients with aniridia and the authors often use them because of the poor results of medical therapy or filtering surgery. However, when the elevated intraocular pressure is associated with black diaphragm lenses for aniridia, most authors decide to carry out a filtering technique. The current authors opted for the implantation of an Ahmed valve in three patients, two with traumatic aniridia and the other with a congenital case. Every patient had a different kind of black diaphragm lens for aniridia. RESULTS. The Ahmed valve controlled the intraocular pressure in levels below 20 mmHg for a follow-up year with no complications derived from its application. CONCLUSIONS. Ahmed valve implantation was the best technique to decrease intraocular pressure in patients with aniridia. The authors have used it successfully for cases with elevated pressure associated with black diaphargm lenses for aniridia.