1. Introduction

Several femtosecond (FS) laser platforms have been developed to automate certain steps during cataract surgery, such as clear corneal incision (CCI), capsulotomy, and nucleus fragmentation [1–5]. An increasing number of studies are reporting data on the safety and efficacy of FS laser platforms to create anterior capsulotomy [6–8]. Overall, the FS laser capsulotomies have been shown to be better centered than manual CCC, with highly predictable diameters [1, 7, 9]. Previous studies suggest that optimal capsulotomy centration and accurate size may maximize the performance of premium intraocular lenses (IOLs) [10, 11]. Nevertheless, recent work [12] has reported greater incidence of capsular tears using FS commercial laser platform, compared to conventional phacoemulsification surgery, even beyond the initial learning curve expected with the technology [6]. Several studies [8, 12–15] have analyzed the lens capsulotomies using either optical or scanning probe microscopy techniques. The light optical microscopy has been mainly used to monitor lens epithelial cell (LEC) death after capsulotomy. High-resolution scanning electron microscopy (SEM) imaging has revealed irregularities at the capsulotomy edges, which have not been observed in manual capsulorhexis (CCC). Overall, variations in laser settings have been shown to affect the morphology of capsulotomy cutting edges [12–15]. It is therefore of great interest to understand the source(s) of these microstructural irregularities and how to prevent them to optimize the surgical outcome of FS laser assisted cataract surgery.

The purpose of our study was to analyze, using environmental scanning electron microscopy (eSEM), the morphology and irregularity of the capsulotomy cutting edges obtained using two FS commercial laser cataract platforms, in comparison with manual CCC.