ABSTRACT
Filtering surgery is usually indicated when the patient’s glaucoma is worsening or progression of glaucomatous damage is anticipated at the present level of intraocular pressure, despite using the maximum tolerated medical or laser therapy. Good surgical exposure is critical for the successful outcome of any filtering procedure. The placement of the filtration opening as close to the base of the scleral flap as possible is of crucial importance. A corneoscleral block excision is not required if the surgeon chooses to use the EX-PRESS glaucoma filtration device. In many patients, glaucoma filtration surgery can halt or at least slow the progression of what would otherwise be a relentlessly progressive vision loss from glaucoma. Successful filtration surgery requires diligent attention to details of performance. The basic principle of guarded filtering surgery is to create a partial thickness scleral flap overlying a fistulous opening at the limbus, effectively connecting the anterior chamber to the intrascleral and subconjunctival spaces.
