Pathogenesis and management of the lens-iris diaphragm retropulsion syndrome during phacoemulsification.

After the ultrasonic tip is introduced into the highly myopic eye and inflow is activated, the anterior chamber deepens, the lens-iris diaphragm is displaced posteriorly, the iris becomes concave, and the pupil dilates from the weight of the water column above the eye. We define a known but undescribed syndrome--the lens-iris diaphragm retropulsion syndrome (LIDRS)--which is thought to be caused by abnormally loose zonules. The surgeon's reflexive action, lowering the infusion bottle height, reduces the weight of the water column but also reduces the infusion limit. We managed this situation with an inflow-splitting technique in which the infusion bottle height was lowered significantly and a Lewicky chamber maintainer connected to a second infusion bottle at the same height as the first bottle was introduced into the anterior chamber. Pressure monitoring that enabled simultaneous, synchronized recording of phacoemulsification and intraocular pressure fluctuations was used.