Objective: To compare surgical outcomes following penetrating keratoplasty (PK), Descemet stripping endothelial keratoplasty (DSEK), and Descemet membrane endothelial keratoplasty (DMEK) in patients with iridocorneal endothelial (ICE) syndrome.

Methods: Systematic review and meta-analysis on individual patient data (IPD). Methods: Pre-registration was performed in the PROSPERO database (registration number: CRD42024539444). Eligible studies from Embase, MEDLINE (via PubMed), and the Cochrane Central Register of Controlled Trials (CENTRAL) were retrieved up to April 24, 2024. Studies were included those reporting clinical outcomes after PK, DSEK, or DMEK- graft survival, best spectacle-corrected visual acuity (BSCVA) and endothelial cell density (ECD) - in people with ICE syndrome. Cochrane Handbook was followed for data extraction/ synthesis, and the Risk of Bias in Non-randomized Studies of Interventions (ROBINS-I) and the Joanna Briggs Institute Critical Appraisal Checklists were used to assess risk of bias. Meta-analyses were conducted using a random-effects model. Heterogeneity between studies was assessed using Q-test and I2 statistics.

Results: Nineteen of the 1963 screened studies were included in the meta-analysis. Multivariate pooled Kaplan-Meier curves with 95% confidence intervals, based on IPD from studies with at least 10 cases indicated that graft survival was better after PK compared to DSEK in patients with ICE syndrome. No significant difference (p=0.92) was found in BSCVA improvement between PK [-0.77 (95% CI, -1.45 to -0.09)], DSEK [-0.87 (95% CI, -1.35 to -0.39)] and DMEK [-0.85 (95% CI, -1.07 to -0.62)]. No significant differences in ECD were observed between DSEK and DMEK 6 (p=0.88) and 12 months (p=0.33) postoperatively. IPD analysis revealed no significant difference in graft survival between patients with and without anytime glaucoma (-0.04 ± 0.50 SEM; p=0.940) or cataract surgery (-0.45 ± 0.40 SEM; p=0.265).

Conclusions: PK demonstrated better graft survival compared to DSEK in patients with ICE, however, further research and additional evidence are needed to draw more definitive conclusions. Improvements in BSCVA were comparable across PK, DSEK and DMEK. Glaucoma surgery, whether performed before or after keratoplasty, appear to have no significant impact on graft survival.