Visual Acuity Outcomes after Phacoemulsification in Eyes with Good Visual Acuity before Cataract Surgery.

OBJECTIVE To analyze cataract surgery outcomes and related factors in eyes presenting with good visual acuity. SUBJECT AND METHODS Retrospective longitudinal of patients undergoing phacoemulsification between the years 2014-2018 in Moorfields Eye Hospital and satellite units. Pre- and postoperative visual acuity (unaided, with glasses, with pinhole) were analyzed. Inclusion criteria were age≥40 years and pinhole visual acuity ≥6/9 preoperatively. Exclusion criteria were no postoperative visual acuity data. VA change variable was also defined according to postoperative visual acuity being above or below the Snellen 6/9 threshold. RESULTS 2720 eyes were included in the analysis. The unaided LogMAR visual acuity improved from 0.54 to 0.20 (p<0.001), the LogMAR visual acuity with glasses improved from 0.35 to 0.05(p<0.001) and the LogMAR pinhole visual acuity improved from 0.17 to 0.13(p<0.001). 8.1% of patients had Snellen visual acuity <6/9 postoperatively. Mean follow up period was 23,6±9.9 days. In multivariate logistic regression, factors associated with visual acuity <6/9 postoperatively were: age [OR=0.96, 95% CI (0.95, 0.98), p<0.001], vitreous loss [OR=0.21, 95% CI (0.08, 0.56), p=0.002] and iris trauma [OR=0.28, 95% CI (0.10, 0.82) p=0.02]. No significant adverse events occurred. CONCLUSIONS Visual acuity improved significantly overall in this group of patients, although at least 8.1% of them did not reach their pinhole preoperative visual acuity. Worse visual acuity outcomes were associated with increasing age, vitreous loss and iris trauma. The 6/9 vision threshold may not be able to accurately differentiate those who may benefit from cataract surgery and those who may not.