Study of Effect of Nd:YAG Capsulotomy on Corneal Endothelium: A Teaching Hospital Based Prospective study

Abstract

Introduction: Posterior Capsular Opacification (PCO) is a condition which develops months or years after cataract surgery. The Neodymium Yttrium Aluminium Garnet (Nd:YAG) laser capsulotomy is the procedure of choice for PCO and its adverse effects include intraocular pressure elevation, cystoid macular oedema, corneal endothelial cell damage, retinal detachment and Intraocular Lens (IOL) pitting. Aim: To assess the corneal endothelial structure and function before and after Nd:YAG laser capsulotomy in patients with PCO using specular microscopy. Materials and Methods: This was a prospective observational study carried out in Bharati Vidyapeeth (Deemed to be University) Medical College and Hospital, Sangli, Maharashtra, India on 50 eyes of 50 patients having PCO. This study was conducted in the time period between October 2020 to February 2021 for four months. Patients were subjected to Nd:YAG laser capsulotomy in the affected eye and were followed-up at one week and one month postprocedure. Specular Microscopy was used to evaluate the Endothelial Cell Density (ECD), Coefficient of Variation (CV) and Hexagonality of endothelial cells before and after laser capsulotomy. Statistical Package for Social Sciences (SPSS) version 26.0 was used for the statistical analysis. Chisquare test and ANOVA test are the tests of significance applied in this study. Results: Forty-five patients (90%) gained Best Corrected Visual Acuity (BCVA) of >6/18 after one week and 47 patients (94%) gained BCVA of ≥6/18 after one month postprocedure. Mean ECD prelaser was 2356.76 cells/mm2 , which decreased to 2231.8 cells/mm2 at one week and 2199.2 cells/mm2 at one month follow-up. The difference between prelaser ECD and at one week and one month was 124.96 cells/mm2 and 157.56 cells/mm2 , respectively, which was statistically significant at one month (p<0.0001). The mean CV prelaser was 33.74, at one week was 35.58 and at one month it was 37.22. The difference in CV from prelaser status to one month was statistically significant (p<0.0001). The mean hexagonality at baseline was 65.34% which decreased to 62.02% at one week and 60.42% at one month follow-up. The difference in hexagonality between one month and baseline was statistically significant (p<0.0001). Conclusion: Nd:YAG laser capsulotomy is a safe, effective and non invasive method for the treatment of PCO. However, it causes structural and functional corneal endothelial cell damage.

Keywords

• capsular opacification
• corneal endothelial cell damage
• posterior capsulotomy
• solid-state laser