Pupil snap, described by Dr. Ronald Yeoh, is an ominous sign during a phacoemulsification procedure, marking the breakage of the posterior capsule followed by momentary constriction of the pupil, like a quick snap, as seen in Figure 1.
Performing hydrodissection is an important step during phacoemulsification. Multiple quadrant hydrodissection helps to diffuse fluid evenly, forming a good cushioning effect for the nucleus and thereby separating it from the capsule from all sides. Thick cortical adhesions often prevent the free seepage of fluid; forceful injection leads to buildup of fluid that