Reverse Pupillary Block

reverse pupillary block

Reverse pupillary block is an eye condition where the pressure balance between the front and back of the iris creates an abnormal backward bowing of the iris toward the lens. This backward bowing increases contact between the back surface of the iris and nearby structures such as the lens zonules, which can rub away tiny pigment granules and release them into the eye. That released pigment can then clog the eye’s drainage system and raise internal eye pressure, increasing the risk of optic nerve damage if not monitored. The situation is different from the more familiar forward bowing that causes angle-closure; here the geometry makes the iris press inward toward the lens instead of outward. People with certain eye shapes or anatomy are more likely to experience this pressure imbalance, and activities that change the eye’s dynamics may make it worse. Eye doctors diagnose this by observing the iris shape and measuring eye pressure and drainage angle during an exam. Treatment aims to stop the harmful rubbing and normalize fluid flow, which may include medications, laser procedures, or surgical options depending on severity. Recognizing and addressing reverse pupillary block matters because it can be the starting point for pigment release and a form of glaucoma that threatens vision if left unchecked.