Phaco-Chop versus Divide-and-Conquer in Patients Who Underwent Cataract Surgery: A Systematic Review and Meta-Analysis.

Abstract

Cataract surgery is one of the most frequently performed eye surgeries worldwide, and among several techniques, phacoemulsification has become the standard of care due to its safety and efficiency. We evaluated the advantages and disadvantages of two phacoemulsification techniques: phaco-chop and divide-and-conquer. PubMed, Cochrane, Embase, and Web of Science databases were queried for randomized controlled trial (RCT), prospective and retrospective studies that compared the phaco-chop technique over the divide-and-conquer technique and reported the outcomes of (1) Endothelial cell count change (ECC); (2) Ultrasound time (UST); (3) Cumulated dissipated energy (CDE); (4) Surgery time; and (5) Phacoemulsification time (PT). Heterogeneity was examined with I2 statistics. A random-effects model was used for outcomes with high heterogeneity. Nine final studies, (6 prospective RCTs and 3 observational), comprising 837 patients undergoing phacoemulsification. 435 (51.9%) underwent the phaco-chop technique, and 405 (48.1%) underwent divide-and-conquer. Overall, the phaco-chop technique was associated with several advantages: a significant difference in ECC change postoperatively (Mean Difference [MD] -221.67 Cell/mm2; 95% Confidence Interval [CI] -401.68 to -41.66; p < 0.02; I2=73%); a shorter UST (MD -51.16 sec; 95% CI -99.4 to -2.79; p = 0.04; I2=98%); reduced CDE (MD -8.68 units; 95% CI -12.76 to -4.60; p < 0.01; I2=84%); a lower PT (MD -55.09 sec; 95% CI -99.29 to -12.90; p = 0.01; I2=100). There were no significant differences in surgery time (MD -3.86 min; 95% CI -9.55 to 1.83; p = 0.18; I2=99%). The phaco-chop technique proved to cause fewer hazards to the corneal endothelium, with less delivered intraocular ultrasound energy when compared to the divide-and-conquer technique.