Descemet stripping automated endothelial keratoplasty (DSAEK) for isolated endothelial dysfunction has become the preferred surgical option for many corneal surgeons. However, there are limited large-scale reports on DSAEK survival and clinical variables affecting the risk of rejection and failure after failed penetrating keratoplasty (PK).
Here, the authors of a multicenter, retrospective, interventional case series report the survival, risk factors for graft rejection and failure, and visual outcome of DSAEK after failed PK. They included patients recruited from six tertiary referral surgical centers: three in the United States, two in Europe, and one in Asia. A total of 246 consecutive eyes (246 patients) that underwent DSAEK after failed PK, with a minimum follow-up period of one month, were included. Furthermore, data comprising demographic details, preoperative and postoperative risk factors, time to rejection, time to failure, and corrected distance visual acuity were collected. Cumulative probability of graft survival, hazard ratio estimates for survival, and corrected distance visual acuity were determined as the main outcomes and measures.
According to the authors, the mean (SD) recipient age was 63.2 (16.6) years and the median follow-up period was 17 months (interquartile range, six to 30 months). One-third of the grafts (n=82) had follow-up data for more than two years; 18.3% had more than one failed PK before DSAEK. In total, 19.1% (47 of 246) of DSAEK grafts failed. The study authors reported that the cumulative probability of DSAEK survival after a failed PK was 0.89 (95% CI, 0.84 to 0.92), 0.74 (95% CI, 0.64 to 0.81), and 0.47 (95% CI, 0.29 to 0.61) at one year, three years, and five years, respectively. Based on multivariate analysis, they determined that significant preoperative risk factors for failure were young recipient age (hazard ratio [HR], 5.18 [95% CI, 1.57 to 17.18]), previous tube filtration surgery (HR, 5.23 [95% CI, 1.47 to 7.33]), and rejection episodes before PK failure (HR, 3.28 [95% CI, 1.47 to 7.33]); single-surgeon centers had a protective effect. Any rejection episode prior to PK failure was a significant predictor of post-DSAEK rejection, which in turn was a significant predictor of DSAEK failure. After a median follow-up of 17 months, 33.3% of the grafts achieved ≥0.3 logMAR (20/40) corrected distance visual acuity.
DSAEK after failed PK combines greater wound stability and reduced suture-related complications, with visual outcomes and graft survival rates comparable to those of a second PK.