Abstract
Abstract: :
Purpose: It has been well documented that the final Snellen visual acuity after DLEK may be reduced compared to conventional penetrating keratoplasty, despite lower astigmatism. The etiology of this is unclear, however some investigators suggest that interface opacity, posterior corneal vaulting, and higher order wavefront aberrations may play a role. The purpose of this study is to determine if the use of automated microkeratome systems to create the donor lenticule produces a superior visual outcome in DLEK as compared to manual dissection. Methods: : Thirty consecutive patients underwent DLEK. Eighteen had surgery using the Moria ALTK automated microkeratome system, while twelve had surgery using the Bausch and Lomb artificial anterior chamber with manual dissection. Postoperatively, the mean best corrected Snellen visual acuity, corneal topographic astigmatism (Humphrey Atlas), endothelial cell count (Nidek Confocal System), interface opacity (Oculus Pentacam), and higher order wavefront aberrations (Tracey) were determined at 1 month, 3 months, and 6 months. Results: The mean best corrected Snellen vision at 3 and 6 months was 20/35 and 20/32 in the automated group and 20/55 and 20/51 in the manual group. Corneal topographic cylinder at 3 and 6 months was 3.06 D and 0.875 D in the automated group and 3.478 D and 1.42 D in the manual group. Early results show no significant difference in interface opacity, endothelial cell counts, or higher order wavefront aberrations between the two methods. Three buttonhole flaps occurred in the automated group, while there were no intraoperative complications in the manual group. Conclusions: Early results suggest that use of automated microkeratome systems may provide faster visual rehabilitation in DLEK as compared to manual systems. The inadvertent microkeratome complications which may occur should alert the surgeon to the fact that intraoperative pachymetry is important, as well as having access to various microkeratome head sizes so that the lenticule thickness may be adjusted in cases of thin donors buttons.
Keywords: cornea: endothelium • cornea: clinical science • transplantation