Alteração refracional após capsulotomia posterior com laser Nd:YAG

Abstract

Objective: To identify if there is a significant change on refraction after Nd:YAG laser posterior capsulotomy in pseudophakic eyes. Methods: A retrospective study with analysis of medical records of patients treated at a hospital, with diagnosis of opacification of posterior lens capsule treated with Nd:YAG laser posterior capsulotomy, from October 2019 to March 2021. The comparison of refraction before and after the procedure was performed by calculating the spherical equivalent. Changes in visual acuity (VA), measured by LogMAR, were also evaluated. Results: A total of 90 medical records (140 eyes) of patients submitted to Nd:YAG laser posterior capsulotomy were analysed. The mean pre-procedure spherical equivalent was -0.07±0.89D, minimum of -3.0D and maximum of +2.5D, median (interquartile range) of 0.0D (-0.50D to +0.375D). The postprocedure mean was -0.18±0.86D, minimum of -3.5D and maximum of +2.25D, median (interquartile range) of -0.125D (-0.50D to 0.0D), with p <0.0082. Of the 140 eyes, 66 underwent myopia and 37 hyperopia, the mean change in the general spherical equivalent was -0.12±0.51D, minimum -2.50D and maximum +1.25D, median (interquartile range) of 0.0D (-0.375D to +0.125D). When comparing the difference between the spherical equivalent before and after the procedure of the group of eyes that underwent myopia (n=66) or hyperopia (n=37), separately, both obtained p<0.0001. When comparing all eyes that suffered any change on refraction (n=103), the p value was 0.008. The mean pre-procedure visual acuity was 0.23±0.32, minimum of 0.0 and maximum of 2.3. After the procedure, the mean was 0.06±0.13, minimum of -0.12 and maximum of 0.7, p<0.0001. Conclusion: Nd:YAG laser posterior capsulotomy significantly improved visual acuity of patients in this study; however, it also led to a significant change on refraction after the procedure, both for myopization, which was more frequent, and for hyperopization.