Pros and cons of DSAEK
DSAEK may be considered for failed PKs because it potentially has a lower risk of rejection and higher long-term graft survival.
As a caveat, however, DSAEK cannot be performed if there is significant pre-existing, irreversible stromal damage or distortion in the PK, Dr. Tan said.
Dr. Tan used the term “potentially” because there are some conflicting data in the literature. A study by Anshu et al. that included 60 cases that had DSAEK after failed PK reported a DSAEK graft survival rate of 74% at 4 years. The rate reached 96% in eyes without a glaucoma shunt, but it was only 22% in those with a glaucoma shunt.
In contrast, the ACGR showed PK may deliver a better graft survival rate than EK after a failed PK that was initially performed for keratoconus or pseudophakic bullous keratopathy.
“But you have to understand the setting of the Australian registry, and so we need to remove the effect of the DSAEK learning curve,” Dr. Tan said. “In our own study, comparing PK with DSAEK and anterior lamellar keratoplasty (ALK), DSAEK and ALK had significantly better graft survival than PK.”
Looking specifically at previous failed PKs, data from the SCTS showed DSAEK was far superior to repeat PK. At 5 years, graft survival rates were just 51% for repeat PK and 86.5% for eyes that had DSAEK.”