Endothelial keratoplasty a better bet for repeat corneal transplantation in Asians

In case of failed corneal transplants, performing subsequent endothelial keratoplasty (EK) instead of penetrating keratoplasty (PK) significantly improves long-term regraft survival and visual outcomes, according to a study from Singapore.

Analysis of data on consecutive patients who had repeat keratoplasty at Singapore National Eye Centre showed that among those who had graft failure after the initial PK or EK, the probability of regraft survival at 5 and 10 years was higher for patients who underwent regraft using EK vs PK (PK/EK: 74.2 percent and 69.2 percent; EK/EK: 67.3 percent and 52.8 percent; PK/PK: 47.9 percent and 43.1 percent; p=0.002 for PK/EK vs PK/PK and p=0.002 for EK/EK vs PK/PK). [Front Med 2025;11:1503333]

The same was true for best corrected visual acuity (BCVA) at 1 year after the regrafting procedure. Patients in the PK/PK group had the worst visual outcomes, with PK/PK being associated with worse postoperative BCVA compared with PK/EK (p=0.006) and EK/EK (p<0.001). Meanwhile, the PK/EK and EK/EK groups had equally good postoperative visual outcomes (p=0.295).

“Regrafts performed for failed initial deep anterior lamellar keratoplasty (DALK) grafts did well regardless of the method,” the investigators said, noting that regraft survival was 100 percent for DALK/PK, DALK/DALK, and DALK/EK at 3 to 5 years.

In multiple Cox regression models, the risk factors for regraft failure were male sex (p=0.023), PK regraft (p=0.003), regraft rejection (p=0.003), and initial graft indications of pseudophakic bullous keratopathy (p=0.005), and aphakic bullous keratopathy (p=0.004). Conversely, longer time to regraft was associated with decreased risk of failure (p=0.013).

The investigators pointed out that high-risk regrafts had significantly lower 10-year survival probabilities compared with nonhigh-risk regrafts (p=0.045).

The analysis included 284 eyes which had a previous failed primary graft and underwent a regraft. The method used for repeat corneal transplantation was Descemet stripping automated EK in 181 eyes, PK in 63, Descemet membrane EK in 21, and DALK in 19. The main causes of graft failure requiring repeat corneal transplantations were graft rejection (38.4 percent) and late endothelial failure (15.8 percent).

“A rejection episode in any graft or regraft is associated with a significantly greater risk of failure for that graft, in addition to further episodes of rejection. Prior graft failure is inherently another high-risk factor in repeat keratoplasty, especially if it was due to allograft rejection,” the investigators said. [Cornea 2019;38:1077-1082; Clin Experiment Ophthalmol 2019;47:987-994; J Ophthalmol 2021;2021:1-8; Curr Ophthalmol Rep 2017;5:38-48]

“Repeat transplant patients at our centre undergo more frequent follow-ups and slower tapering of topical corticosteroids. High-risk patients are given additional topical and systemic immunosuppression. This requires collaboration with a rheumatologist and close monitoring of blood chemistry,” they added.

The study was limited by its modest sample size and retrospective design, among others. Nevertheless, the investigators stressed that their graft registry data remains valuable, as it represents real-world data of clinical outcomes of repeat keratoplasties following a failed optical PK, EK, or DALK in an Asian population.