Randomized clinical trial of deep lamellar keratoplasty vs penetrating keratoplasty

PURPOSE: To prospectively compare the safety and efficacy of deep lamellar keratoplasty (DLKP) and penetrating keratoplasty (PKP). DESIGN: Prospective, randomized clinical trial. METHODS: Consecutive 26 eyes of 24 patients who had stromal opacity without endothelial abnormalities were randomly assigned to either PKP or DLKP. Best-corrected visual acuity (BCVA), contrast visual acuity, glare test, intraocular pressure, corneal topography, endothelial density, and pachymetry were measured before and after surgery. RESULTS: Two eyes in the DLKP had rupture of the Descemet membrane and one of the eyes developed endothelial decompensation. One eye in the PKP group showed decreases in vision due to secondary glaucoma. None of the eyes developed immunologic rejection. The PKP group showed a tendency of faster recovery in BCVA than the DLKP group, but the difference was not statistically significant. Contrast visual acuity, glare test, and corneal topography did not show significant differences between the two groups. The intraocular pressure was significantly higher at 12 months in the PKP group (P = .004), but not in the DLKP group (P = .41) compared with preoperative values. While the PKP group showed progressive decrease in endothelial density over 24 months, this was not observed in the DLKP group after surgery. Difference in endothelial density at 24 months reached statistical significance (P = .04). CONCLUSIONS: We found that DLKP was superior to PKP in its safety such as continuous decreases of endothelium or increases in intraocular pressure. However, endothelial damage can also occur in DLKP, especially in cases of intraoperative Descemet membrane rupture. With the development of easier surgical techniques, DLKP may be a first choice of keratoplasty in most eyes without endothelial abnormalities.