Effect of Preoperative Ocular Surface Optimization on Biometric Accuracy and Refractive Outcomes After Cataract Surgery: A Systematic Review with Narrative and Exploratory Quantitative Synthesis

Abstract

Background The ocular surface and tear-film instability can affect keratometry and biometry before cataract surgery. This review evaluated whether preoperative ocular surface optimization improves biometric accuracy, keratometric repeatability, intraocular lens (IOL) power prediction, and postoperative refractive outcomes. Methods PubMed/MEDLINE was searched on 24 June 2026 and Cochrane CENTRAL on 1 July 2026 without language, study-type, age, or date filters. One reviewer screened records in Rayyan and the exported CENTRAL trial list, assessed full texts against prespecified eligibility criteria, and extracted study data; screening and extraction were not independently duplicated. The primary synthesis was narrative because study designs and outcome reporting were heterogeneous, with exploratory random-effects sensitivity analyses performed only for sufficiently compatible datasets. Results PubMed identified 179 records and CENTRAL identified 44 trial records. PubMed screening selected 23 records for full-text review. CENTRAL added two completed published studies and identified five registry-only records awaiting results. Overall, 25 completed published studies were included, while five registry-only records were tracked but not synthesized. Heterogeneity in interventions, comparators, and outcomes limited quantitative pooling. Conclusions Preoperative ocular-surface optimization may improve the stability of cataract measurements and refractive prediction in selected patients, particularly when dry eye disease, meibomian gland dysfunction, tear-film instability, or ocular-surface irregularity is present. Heterogeneity and predominantly nonrandomized evidence preclude a definitive pooled treatment effect. Final biometry should be performed after clinically significant ocular-surface disease has been treated and the surface is reasonably stable.