Pharmacologic interventions for mydriasis in cataract surgery.

backgroundCataract surgery is one of the most common surgical procedures performed worldwide. Achieving appropriate intraoperative mydriasis is one of the critical factors associated with the safety and performance of the surgery. Inadequate pupillary dilation or constriction of the pupil during cataract surgery can impair the surgeon's field of view and make it difficult to maneuver instruments.

objectivesTo evaluate the relative effectiveness of achieving pupillary dilation during phacoemulsification for cataract extraction using three methods of pupillary dilation: topical mydriatics, intracameral mydriatics, or depot delivery systems. We also planned to document and compare the risk of intraoperative and postoperative complications following phacoemulsification for cataract extraction, as well as the cost-effectiveness of these methods for pupillary dilation. SEARCH

methodsWe searched the Cochrane Central Register of Controlled Trials (CENTRAL), which contains the Cochrane Eyes and Vision Trials Register) (2021, Issue 1); Ovid MEDLINE; Embase.com; PubMed; Latin American and Caribbean Health Sciences Literature Database (LILACS); ClinicalTrials.gov; and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). We did not use any date or language restrictions in the electronic search for trials. We last searched the electronic databases on 22 January 2021. SELECTION CRITERIA: We included only randomized controlled trial (RCTs) in which participants underwent phacoemulsification for cataract extraction. DATA COLLECTION AND ANALYSIS: We followed standard Cochrane methodology. MAIN

resultsWe included a total of 14 RCTs (1670 eyes of 1652 participants) in this review. Of the 14 trials, 7 compared topical versus intracameral mydriatics, 6 compared topical mydriatics versus depot delivery systems, and 1 compared all three methods. We were unable to calculate overall estimates of comparative effectiveness for most outcomes due to statistical heterogeneity among the estimates from individual studies or because outcome data were available from only a single study. Furthermore, the certainty of evidence for most outcomes was low or very low, due primarily to imprecision and risk of bias. Comparison 1: topical mydriatics versus intracameral mydriatics Four RCTs (739 participants, 757 eyes) of the 8 RCTs that had compared these two methods reported mean pupillary diameters at the time surgeons had performed capsulorhexis; all favored topical mydriatics, but heterogeneity was high (I AUTHORS'

conclusionsData from 14 completed RCTs were inadequate to establish the superiority of any of three methods to achieve mydriasis for cataract surgery, based on pupillary dilation at different times during the surgery or on time required for surgery. Only one trial had a sample size adequate to yield a robust effect estimate. Larger, well-designed trials are needed to provide robust estimates for the comparison of mydriasis approaches for beneficial and adverse effects.