Comparison of Femtosecond Laser Assistance and Manual Trephination in Deep Anterior Lamellar Keratoplasty in the Treatment of Keratoconus: A Meta-Analysis

Abstract

To compare the efficacy and safety of femtosecond laser-assisted deep anterior lamellar keratoplasty (F-DALK) with those of manual-trephination DALK (M-DALK) in treating keratoconus. Systematic review and meta-analysis. Through November 2022, we comprehensively searched PubMed, EMBASE, the Cochrane Library, and 4 Chinese databases. Studies that involved comparisons between F-DALK and M-DALK groups and that reported on relevant efficacy and/or safety parameters were included. Primary outcomes were uncorrected- and corrected-distance visual acuity and intraoperative complication rates. Secondary outcomes were spherical equivalent, topographic astigmatism, refractive cylinder, mean keratometry, endothelial cell density, suture removal time, and postoperative complication rates. These data were analyzed using Cochrane Review Manager software version 5.3. This meta-analysis included 9 nonrandomized controlled studies involving 1713 eyes. In eyes treated with F-DALK, corrected-distance visual acuity at 1 to 6 months (weighted mean difference=-0.07 [95% confidence interval {CI} -0.10 to -0.03]; I2=0%; P < .001) after surgery was better and intraoperative Descemet membrane perforation occurred less often (odds ratio=0.53 [95% CI 0.31-0.92]; I2=6%; P=.02) than in eyes treated with M-DALK. No clinically significant differences in other outcomes were found among the groups. Both F-DALK and M-DALK are safe and efficacious for patients with keratoconus. Compared with M-DALK, F-DALK can provide better early visual acuity and reduce the intraoperative perforation rate, and its likely improvements to long-term visual quality and endothelial cell preservation warrant further investigation. In addition, the 2 techniques seem to be comparable regarding refractive outcomes and other complications.