Thirty-six-month outcomes of femtosecond laser-assisted DSEK and PKP for corneal endothelial decompensation

Abstract

To describe and compare the 36-month outcomes associated with femtosecond laser-assisted Descemet stripping endothelial keratoplasty (FS-DSEK) and femtosecond laser-assisted penetrating keratoplasty (FS-PKP) for corneal endothelial decompensation under indication-based surgical selection. This single-center, retrospective, nonrandomized cohort study included 130 consecutive eyes of 130 patients who underwent FS-DSEK or FS-PKP at Nanjing First Hospital, Nanjing Medical University, between July 2016 and June 2021. All included eyes had 36 months of follow-up, with data collection completed in June 2024. Procedure selection was based on pathological depth and the severity of corneal structural involvement. Visual acuity, central corneal thickness (CCT), ocular discomfort symptoms, refractive parameters, endothelial biomarkers, graft survival, and postoperative complications were evaluated. Longitudinal outcomes were analyzed using generalized estimating equations, and graft survival was estimated using Kaplan-Meier analysis. Baseline demographic, preoperative ocular, donor-related, and recorded indication variables did not differ significantly between groups. The median time to corneal transparency was shorter in the FS-DSEK group than in the FS-PKP group [4.0 (3.0, 5.25) vs. 5.0 (4.0, 7.0) days, P  = 0.008]. Both groups showed improvement in ocular discomfort and CCT during follow-up. FS-DSEK was associated with more rapid early-to-intermediate improvement in uncorrected and best-corrected visual acuity, whereas visual outcomes were similar by 36 months. Spherical equivalent remained stable in both groups, while absolute astigmatism was lower after FS-DSEK. Endothelial cell density decreased in both groups; early-to-intermediate endothelial cell loss was greater after FS-DSEK and the difference was no longer statistically significant at 24 or 36 months. The 36-month graft survival rates were 86.7% and 75.8% in the FS-DSEK and FS-PKP groups, respectively, without a significant difference ( P  = 0.198). Graft dislocation occurred only in the FS-DSEK group. In this indication-based cohort, FS-DSEK was associated with faster corneal clearance, earlier visual recovery, and lower postoperative absolute astigmatism in eyes whose anterior stroma was expected to regain transparency. FS-PKP remained necessary for eyes with irreversible stromal opacity, scarring, degeneration, or full-thickness structural defects. The findings support complementary, anatomy-based procedure selection with procedure-specific postoperative surveillance.