Preoperative Diquafosol vs. Intense Pulsed Light with Gland Expression for MGD: Effects on Refractive Accuracy and Tear Film Stability in Cataract Surgery

<b>Objectives</b>: To compare the effects of two preoperative dry eye treatments-3% diquafosol sodium (DQS) and intense pulsed light with meibomian gland expression (IPL-MGX)-on refractive accuracy in cataract surgery and identify tear break-up time (TBUT) thresholds predictive of refractive success. <b>Methods</b>: In this prospective, paired-eye study, 62 patients (124 eyes) with meibomian gland dysfunction underwent bilateral cataract surgery with the same trifocal intraocular lens. One eye received DQS, while the fellow eye underwent four IPL-MGX sessions before biometry. Postoperative absolute prediction error (P-SE) was compared. TBUT and higher-order aberrations (HOAs) were evaluated. Logistic regression identified predictors of refractive accuracy, and receiver operating characteristic (ROC) analysis assessed the predictive value of TBUT for P-SE thresholds of <0.25 D and <0.50 D. <b>Results</b>: P-SE was significantly lower in IPL-MGX-treated eyes than in DQS-treated eyes (mean paired difference -0.11 D, <i>p</i> < 0.001). Success rates within <0.25 D and <0.50 D were higher with IPL-MGX (<i>p</i> < 0.01). TBUT and HOAs were predictors in univariate models, but only TBUT remained significant in the multivariable analysis (odds ratio, 4.90 per 1-s increase; 95% confidence interval, 1.92-12.51; <i>p</i> < 0.001). ROC analysis supported TBUT cutoffs of 7 s (<0.25 D) and 6 s (<0.50 D). <b>Conclusions</b>: IPL-MGX may improve refractive accuracy compared to DQS. TBUT appeared to be the most consistent predictor, and achieving ≥6 s was associated with higher likelihood of refractive success.