ABSTRACT
Even if the main advantage of non-penetrating filtering surgeries is the low rate of complications, glaucoma surgeons should be aware of intraoperative as well as early and late postoperative complications. A thorough understanding of each specific condition helps in making
the diagnosis and in subsequent management. In case of complete failure of a non-
penetrating filtering surgery, the surgeon may have to contemplate reoperation. This particular situation will also be discussed briefly and several options proposed.
