Cornea - ARVO

ARVO 2013 Annual Meeting Abstracts by Scientific Section/Group - CorneaPurpose: To compare changes in the corneal endothelium after threedifferent keratoplasty techniques for the treatment of endothelialdisease.Methods: Patients with corneal endothelial disease (predominantlyFuchs dystrophy) were enrolled in two consecutive prospectivestudies at Mayo Clinic, Rochester, MN. In a randomized controlledtrial, 28 eyes (26 patients) received penetrating keratoplasty (PK) ordeep lamellar endothelial keratoplasty (DLEK) with a 9 mm scleralincision. In a consecutive prospective observational study, 52 eyes(45 patients) received Descemet-stripping endothelial keratoplasty(DSEK) with a 5 mm scleral incision. Endothelial images wereacquired through 3 years (or 5 years for some eyes after DSEK) byusing confocal microscopy (ConfoScan 3 or 4, Nidek Technologies).Endothelial cell density (ECD) and morphology were determined bythe same masked observer by digitizing the apices of cells (HAI CellAnalysis System) in images acquired at various intervals afterkeratoplasty. Endothelial cell loss (ECL) was the percentage of cellslost from preoperative ECD of the donor tissue, as measured by theeye bank that provided the donor tissue. Endothelial variables werecompared between techniques by using generalized estimatingequation models to account for any correlation between fellow eyesof the same subject.Results: Donor diameter was 7.6 ± 0.1 mm (mean ± sd) for PK, 7.9 ±0.1 mm for DLEK, and 8.2 ± 0.3 mm for DSEK. Preoperative donorECD did not differ between treatments (PK, 2,845 ± 306 cells/mm2;DLEK, 2,749 ± 364 cells/mm2; DSEK, 2,925 ± 374 cells/mm2;p≥0.10). Mean ECL is summarized in the Table. At one month, therewas a trend toward higher ECL after DSEK than after DLEK and PK(p≥0.31, minimum detectable difference, 17% [α=0.05, β=0.20]). At24 and 36 months, ECL after DSEK was lower than it was afterDLEK (p≤0.004) and PK (p≤0.03). At 60 months, ECL after DSEKwas similar to that at 36 months after DLEK and PK. By 3 years,there were 0, 1, and 5 graft failures after PK, DLEK, and DSEK,respectively.Conclusions: Despite a trend toward higher early endothelial cellloss after DSEK, cell loss at 3 years after DSEK is lower than thatafter PK or DLEK. This difference might be related to graft diameteror to postoperative anatomic differences of the posterior cornealsurface. Continued observation is required to determine the longertermtrend in cell loss after DSEK.Purpose: Lamellar corneal grafts are now being performed forindications that previously were treated by full-thickness cornealgrafts. We examined the evidence for the success of these newlamellar procedures, with a focus on graft survival and visualoutcome.Methods: In a national register of >23,000 corneal grafts with up to25 years of annual follow-up, 2983 lamellar grafts were identified, ofwhich 42% were endokeratoplasties (posterior corneal endothelialcell grafts), 39% were traditional, peripheral lamellar keratoplasties,and 19% were deep anterior lamellar keratoplasties (DALKs).Kaplan-Meier plots were used to determine graft survival times, Coxproportional hazards regression was used for multivariate graftsurvival analysis, and visual outcomes were investigated using bestcorrectedSnellen acuity, that is, with any prescribed spectacle lens orcontact lens.Results: Kaplan-Meier graft survival at one year was 74% forendokeratoplasties, 80% for traditional lamellar procedures, and 93%for DALKs. The major indications for endokeratoplasty were Fuchs’dystrophy (47%) and bullous keratopathy (33%). Over the time frame2004-2012, penetrating corneal grafts performed for either of theseindications exhibited significantly better graft survival than didendokeratoplasties for the same indications (p