LIDRS is lens iris diaphragm retropulsion syndrome and it occurs when the iris forms a seal around the anterior capsule causing a reverse pupillary block. This is more common in highly myopic eyes and in cases where the patient had a prior pars plana vitrectomy. The infusion pressure from our phaco probe or I/A probe causes the pressure in the anterior chamber to be much higher than the pressure in the posterior chamber and so we get an overly deep anterior chamber. While lowering the infusion pressure or bottle height can help, that is not the ideal solution. A better move is to break the reverse pupillary block by temporarily lifting up the iris with your chopper. This allows the pressure between the AC and PC to equilibrate and the situation is resolved. If you don’t want to encounter this at all during your cataract surgery in a myopic eye with a prior vitrectomy, simply place a single iris hook to tent up the iris throughout the case.
click to learn how to deal with LIDRS during cataract surgery: