Endothelial cell loss in penetrating keratoplasty, endothelial keratoplasty, and deep anterior lamellar keratoplasty

PURPOSE: To compare endothelial cell density (ECD) loss rates in penetrating keratoplasty (PKP), Descemet's stripping automated endothelial keratoplasty (DSAEK), and deep anterior lamellar keratoplasty (DALK). DESIGN: Single-center, multiple-surgeon, retrospective cohort study. MATERIALS AND METHODS: Patients who received PKP, DSAEK, or DALK from 2009 to 2014 were analyzed (68 vs. 38 vs. 11 patients, respectively). We excluded patients with therapeutic PKP or regraft, infection, endothelial rejection, or uncontrolled glaucoma. Only clear grafts and initial ECD more than 1000 cell/mm(2) were included in the study. The main outcome was ECD loss rate. The follow-up time period was divided into five subgroups: 0–1.5 months, 1.5–6 months, 6–12 months, 12–24 months, and longer than 24 months. RESULTS: Average ECD loss rate (cell/mm(2)/month) declined in all three groups (PKP group: −561.5, −113.2, −36.6, −31.4, and −53.7; DSAEK group: −686.4, −68.3, −21.8, −14.4, and −5.1; DALK group: −576.5, −68, −23.7, 5.9, and 18.3). Although DSAEK group showed faster ECD loss rate in the early postoperative period, it became slower compared to the PKP group within the postoperative 6(th) month and demonstrated significant difference within 2 years. No ECD loss developed in the DALK group after the 1(st) postoperative year; this was significantly different from the PKP group. CONCLUSIONS: Although ECD loss rate in the DSAEK group was initially larger than that in the PKP group, the DSAEK group possessed better long-term endothelial cell survival rate. The DALK group had a lower ECD loss rate than that of the other groups and maintained a stable ECD at 1 year after surgery.