ABSTRACT
The goal of guarded filtering surgery is to create a partial thickness scleral flap at the limbus over - lying a hole punched through the remaining eye wall, effectively connecting the anterior chamber to the outside world. The scleral flap is sutured back into place, with tension on the sutures adjusted to allow a calculated flow out of the hole. The aqueous then collects under the conjunctiva, elevating it and forming a ‘bleb.’ The success of the surgery depends on a constant leak of aqueous through the scleral opening, and the integrity of the conjunctival bleb, so there is no leak of aqueous onto the ocular surface. For this reason, during filtering surgery, the conjunctiva should be handled as little as possible and as meticulously as possible. The conjunctiva overlying the area of the filtration site should never be touched. Non-toothed forceps, such as utility forceps or Pierce-Hoskins forceps, should be used when handling conjunctiva.
