Consequences of mechanical pupil dilation, a study based on the Swedish national cataract register

Abstract

Purpose: To describe the outcomes and demographics of patients undergoing mechanical pupil dilation (MPD) during cataract surgery. Setting: All cataract procedures performed in Umeå University Hospital and Sunderbyn, Gällivare and Piteå hospitals reported to the Swedish National Cataract Register (NCR) during 2013–2019. Design: Retrospective cohort study based on the Swedish NCR and electronic patient records. Methods: The number of control visits, pre- and postoperative visual acuities, surgical complications/intraoperative difficulties, ocular comorbidities and postoperative treatment regimens were retrieved for all cataract procedures with MPD. For each procedure, the consecutive procedure in the NCR from the same clinic without MPD was chosen to form a control group. A multinominal regression analysis with MPD as the dependent variable was performed to identify factors and outcomes independently associated with MPD. Results: A total of 25 349 patients aged 18–97 years underwent cataract surgery in these hospitals during the study period. Of these, 653 (2.6%) had MPD. Factors such as pseudoexfoliations and capsule staining were over-represented among MPD eyes. As a group, eyes with MPD had more postoperative visits and more postoperative anti-inflammatory drops, and more frequently needed augmentation of the anti-inflammatory treatment at the first postoperative visit. Conclusions: MPD is independently associated with a more complicated intra- and postoperative course with more follow-up visits and requires more anti-inflammatory treatment postoperatively. This information could be added to the postoperative counselling, and more postoperative anti-inflammatory treatment could be considered in cases with MPD.