Risk factors for a phacodonesis surprise during cataract surgery in patients with pseudoexfoliation

Purpose: To evaluate the association of different pre-operative parameters with surprise phacodonesis during cataract surgery among patients with pseudoexfoliation (PXF). Materials and methods: This is a retrospective charts review of all PXF patients who underwent cataract surgery between the years 2013 and 2018. Pre-operative parameters (demographics, biometry, intraocular pressure (IOP), endothelial cell count, pupil size, cataract density, glaucoma status, cup to disc ratio, number of glaucoma medications, prior intra-vitreous injections, risk for intraoperative floppy iris syndrome) were compared between patients with and without surprise phacodonesis. Binary logistic regression was used to calculate the predictive value of each parameter. Results: Out of 396 surgical cases with computerized pre-operative assessment, we included 127 eyes of 120 PXF patients without evidence of phacodonesis preoperatively. The mean age was 77.8 ± 12.0 years, 63 (52.7%) were male, and 106 (84.2%) underwent phacoemulsification surgery. We identified 10 cases of surprise phacodonesis during surgery (8.2%). Compared to PXF cases without intraoperative phacodonesis, they had higher pre-operative IOP (23.0 ± 11.0 mmHg vs. 14.9 ± 3.8 mmHg, p < 0.001) and a higher rate of B scan use due to dense cataract obscuring posterior pole evaluation [4 (40%) vs. 15 (12.8%), p = 0.04]. Multivariant binary logistic regression confirmed that only baseline IOP contributed to the prediction of surprise phacodonesis (OR 1.22 CI 1.04–1.43, p = 0.014). Conclusions: Among patients with PXF undergoing cataract surgery, elevated IOP and poor posterior segment visibility requiring B scan use were associated with zonular instability putting these patients at risk for intra-operative complications.