Long-Term Outcomes of Posterior Capsular Opacification in Highly Myopic Eyes and Its Influencing Factors

INTRODUCTION: The purpose of this study was to evaluate the long-term outcomes of posterior capsular opacification (PCO) in highly myopic eyes and its influencing factors. METHODS: Patients undergoing phacoemulsification with intraocular lens implantation and followed up for 1–5 years were included in this prospective cohort study. The severity of PCO was evaluated using EPCO2000 software system, with the area of central 3.0 mm (PCO-3 mm) and within the capsulorhexis (PCO-C) both being analyzed. Percentage of eyes after Nd:YAG capsulotomy, as well as clinically significant PCO (defined as eyes with visual-impairing PCO or after capsulotomy), were also included as outcome variables. RESULTS: A total of 673 highly myopic eyes [axial length (AL) ≥ 26 mm] and 224 control eyes (AL < 26 mm) were analyzed. The mean follow-up time was 34.0 ± 9.0 months. PCO was more severe in highly myopic eyes compared with controls with regard to higher EPCO scores (P < 0.001 for both PCO-3 mm and PCO-C), higher capsulotomy rate (P = 0.001), higher clinically significant PCO rate (P < 0.001) and shorter PCO-free survival time (P < 0.001). Extreme myopia (AL ≥ 28 mm) would further aggravate PCO in terms of higher EPCO scores (PCO-3 mm: P = 0.017; PCO-C: P = 0.013) and higher clinically significant PCO rate (P = 0.024) compared with other myopic eyes. In highly myopic eyes, AL [odds ratio (OR) 1.124, P = 0.004] and follow-up duration (OR 1.082, P < 0.001) were independent risk factors for clinically significant PCO after cataract surgery. CONCLUSION: Highly myopic eyes had more severe PCO in the long term. Longer AL and follow-up duration were associated with higher risk of PCO. CLINICAL TRIAL REGISTRATION: The study was registered at ClinicalTrials.gov (NCT03062085).