Pupil Size After Cataract Surgery

As we age, the pupils become smaller. When cataract surgery is performed it is essential that the pupil be widely dilated allowing for a full view of the anterior surface of the lens. Some patients are on oral medication that reduces the pupil size and creates a floppy iris that interferes with surgery. Flomax and related alpha blockers used for benign prostatic hypertrophy are common problems. 

Before surgery potent pupil dilating drops are administered to create maximal dilation. These pupils usually return to the pre op size after cataract removal. 

In the operating room a small pupil must be enlarged for safe surgery. Most frequently, the pupil is stretched open with smooth iris hooks. Patients do not feel it. In more severe cases a ring like plastic device is implanted to hold the iris open during surgery. It is removed at the end of the operation. Patients do not feel this either.

If the pupil is stretched open or a ring inserted as part of your cataract surgery, the post op pupil is usually larger than before surgery. Over time, the pupil may get smaller but that is hard to predict.  Post op pupils sizes up to approximately 5 mm usually do not create visual problems. However, larger pupils can be associated with visual artifact from light hitting the edge of the intraocular lens. This is particularly true while driving at night. Oncoming headlights can be a real problem. This may be treated with eye drops that shrink the pupil. If problems persist then we can return to the operating room and suture the iris to create a smaller pupil.