DSAEK outcomes

Although posterior lamellar keratoplasty has emerged as the preferred transplantation technique for eyes with corneal endothelial disease, there remains a need for more information on long-term outcomes, reports Jesper Hjortdal MD, PhD. He presented information at the 4th EuCornea Congress in Amsterdam indicating that mid- to long-term graft survival as well as the rate of rejection-related graft failure is similar after Descemet’s stripping automated endothelial keratoplasty (DSAEK) and penetrating keratoplasty (PK). However, DSAEK is associated with fewer rejection episodes. “The years to come will be important in determining the long-term prognosis for eyes undergoing transplantation with new surgical modalities, and we need data from more eyes and with longer follow-up,” said Dr Hjortdal, clinical professor of ophthalmology and head, corneal & refractive surgery, Aarhus University Hospital, Denmark. “Follow-up can be done locally in individual clinics, but national or international corneal registries are an important source of information,” he told EuroTimes. Dr Hjortdal and colleagues at Aarhus University began performing DSAEK in 2006. They analysed data for 202 eyes of 202 patients with Fuchs’ dystrophy who were operated on between January 1, 2000 and December 31, 2010. There were 100 eyes in the DSAEK cohort, all operated on by one surgeon; 102 eyes had PK performed by two surgeons. The two groups were comparable in their median age (82 years) and gender distribution (about two-thirds were female). Six per cent of patients in each group had glaucoma at the time of their transplant procedure. The number of at-risk patients was also similar in the two groups at the various follow-up intervals through five years. PK patients received more intensive corticosteroid treatment after surgery as they were treated with a three-month tapering course of oral prednisone in addition to a topical corticosteroid tapered over one year. Despite this difference, early rejection episodes were more common after PK than after DSAEK. Almost all of the rejections occurred within the first two years after surgery. From three years on, the freedom from rejection rate was similar in the PK and DSAEK groups, ~85 per cent and ~90 per cent, respectively. Treatment for a rejection episode was also more aggressive in the PK group where the regimen included subconjunctival dexamethasone, prednisolone ointment and oral prednisone, whereas DSAEK patients received only topical dexamethasone drops and prednisolone ointment. With these respective regimens, most of the rejection episodes were reversible in both groups. At five years, the freedom from rejection-related failure rate was >95% in both groups. “Typically, the rejection episodes that occur after DSAEK appear less aggressive than those seen after PK, and in our series, all rejection episodes after DSAEK could be controlled with topical steroid drops. However, the long-term cumulative frequency of rejection episodes was similar for the two procedures,” noted Dr Hjortdal. “We know from recent studies that rejection episodes are considerably less frequent after Descemet’s membrane endothelial keratoplasty than after DSAEK and PK. This information supports older experimental findings suggesting higher immunogenicity of the corneal stroma compared with the endothelium.” Considering all causes of graft failure, the five-year survival rate was significantly less in the DSAEK group than for PK, 80 per cent vs. 95 per cent. The difference reflects more early failures after DSAEK. “These data are explained by our learning curve with DSAEK and an attempt with femtosecond laser graft preparation that was associated with interface opacities and a need for regrafting,” said Dr Hjortdal. “However, we can still say that we have a high proportion of functioning grafts at five years after DSAEK.” Slit-lamp photo of a DSAEK-operated patient. Note presence of precipitates on the endothelium of the graft, but not on the peripheral recipient cornea Dr Hjortdal also compared the outcomes he reported with data published by other groups. In a 2013 article from the US, Price et al. analysed graft survival based on three years of prospective follow-up for 173 DSAEK eyes and 1101 PK cases. Limiting the analysis to the Fuchs’ patients, three-year graft survival was 96 per cent in both the DSAEK and PK groups. Rejection-related graft failure rates were 1.7 per cent for the DSAEK eyes and 3.1 per cent for PK, and the difference was not statistically significant. Including the bullous keratopathy cases, the probability of a rejection episode at three years was significantly higher for the PK group than for DSAEK, 20 per cent vs. nine per cent, respectively. “These data on rejection-related failure and rejection episodes correspond to our own findings. We also found rejection episodes were less common after DSAEK, although we had fewer eyes and the difference between groups was not statistically significant,” Dr Hjortdal said. In 2012, Ang et al. from Singapore reported their outcomes for 119 DSAEK eyes and 87 eyes that underwent PK. They also found no significant difference between groups for the three-year graft survival rate (87 per cent, PK 85 per cent) or the rejection-related failure rate (DSAEK 3.4 per cent vs. zero per cent). Dr Hjortdal observed that the lower graft survival rates reported in this study can be explained by the inclusion of eyes with bullous keratopathy in the analysis. Jesper Hjortdal: jesper.hjortdal@dadlnet.dk