Effect of Pars Plana Vitrectomy on Central Corneal Thickness and Its Influence onIntraocular Pressure

Abstract

Purpose: To determine the effect of Pars Plana Vitrectomy on the central corneal thickness(CCT)and its influence on intraocular pressure(IOP). Study Design: Interventional case series. Place and Duration of Study: This research was conducted at Ibrahim Eye Hospital, Karachi, Pakistan, from October 2022 to March 2023. Methods: Forty-one patients of either sexpresenting with posterior segment disease and planned for Pars Plana vitrectomy (PPV) were selected after written informed consent. Pre and post-operative comparison of CCT and IOP was done using paired t-test. Follow-up of readings was done by repeated measures ANOVA test. BCVA measurements were based on the Snellen chart and were converted to the logarithm of the minimum angle of resolution (logMAR) scale for statistical analysis. Results: CCT and IOP of the affected eyes were increased considerably in the first post-operative week (CCT=591 ± 1.5,IOP=28 ± 1.5)and decreased significantly in the 3rd month(CCT=527 ± 1.34, IOP=13 ± 2.5). The change was insignificant at 6thmonth follow-up. BCVA was improved in first week (626 ± 1.34) and remained same throughout the follow-up period. Maximum change in CCT (ΔCCT)was found in age <15 years and in aphakic eyes (119 ± 0.09). Conclusion: Pars Plana vitrectomy causes significant change in CCTwhich can influenceIOP. This change should be kept in mind to prevent false diagnosis of glaucoma in the early post-operative period of PPV. Young patients and Aphakic eyes are more prone to the corneal changes.