Predictive factors and visual outcomes after immediate pars plana vitrectomy for posteriorly dislocated lens fragments during complicated phacoemulsification surgery

Purpose: To investigate the prognostic factors for visual outcome in patients undergoing immediate pars plana vitrectomy (PPV) for posteriorly dislocated lens fragments during phacoemulsification surgery. Methods: This was a single-center, retrospective, cross-sectional study of 37 eyes of 37 patients undergoing immediate PPV for posteriorly dislocated lens fragments from 2015 to 2021. The primary outcome measure was changes in the best-corrected visual acuity (BCVA). Additionally, we analyzed the predictive factors for poor visual outcomes (BCVA <20/40) and perioperative complications. Results: The mean (+/- standard deviation [SD]) age of the patients was 66.57 (+/- 10.86) years, with an almost identical gender profile (M: F = 18/19 [48.64%:51.36%]). The median (interquartile range [IQR]) log of minimum angle of resolution (logMAR) BCVA improved significantly from the baseline (1 [0.6-1.48], similar to 20/200) to the final visit (0.3 [0.2-0.6], similar to 20/40) (P < 0.0001) after a mean (+/- SD) follow-up of 6.35 (+/- 6.32) months. The final BCVA was 20/40 or better in 59.5% of the eyes. Poor final BCVA (<20/40) was associated with small preoperative pupillary size (P = 0.02), presence of preoperative ocular pathology (P = 0.02) including uveitis, glaucoma, and clinically significant macular edema (CSME), intraoperative displacement of >50% of lens matter into the vitreous (P < 0.001), use of iris-claw lens (P < 0.001), and postoperative cystoid macular edema (CME; P = 0.007). The postoperative complications included CME (13.51%), retinal detachment (10.81%), chronic uveitis (8.11%), glaucoma (8.11%), iritis (2.7%), posterior chamber IOL (PCIOL) dislocation (2.7%), and vitreous hemorrhage (2.7%). Conclusion: For retained lens fragments in complicated phacoemulsification surgery, immediate PPV is a viable approach with the potential for a good visual outcome. The important predictors for poor visual outcomes include a small preoperative pupil size, preexisting ocular pathology, displacement of significant volume of lens matter (>50%), use of an iris-claw lens, and CME.