Scleral Perforation and Penetration

Abstract

Scleral perforation is a known and potentially serious complication of strabismus surgery. It can occur at any time during surgery, but most commonly occurs during reattachment of the muscle to the sclera using sutures. The definition a perforation and a penetration depends upon the tissue of reference. By definition, a penetrating injury extends only partially through the tissue of reference while a perforation extends through the full thickness of the tissue of reference (> Fig. 21.1). Thus a scleral perforation extends full thickness through the sclera. If the eye wall (including the sclera, choroid, and retina) is the tissue of reference, then a scleral perforation represents only an eye wall penetration. Perforation of the eye wall, therefore, requires passage of a needle through all of the tissues that constitute the eye wall. Penetration of the sclera occurs in the normal course of strabismus surgery, while perforation of the sclera represents a complication. There is an unsubstantiated, but probably accurate, perception that the incidence of scleral perforation has declined since the evolution of spatula needles in the 1970s.