Abstract
Abstract: :
Purpose: We believe a femtosecond laser (Intralase) would be ideal for dissecting a thin posterior lamella of tissue to be used for endothelial transplantation. In order to have a thin and uniform button, the Intralase application lens must be applied to the posterior side of the donor cornea. Current dogma suggests that the corneal endothelium would be destroyed by applanation with the Intralase delivery lens coupling process. We investigated the use of a viscoelastic "sandwich" to protect the endothelium during laser delivery. Methods:Human eye bank donor buttons were placed endothelial side up, covered with a thin coat of viscoelastic, and brought into contact with the Intralase application lens. A 100 µm button was cut from the endothelial side. The viability of the corneal endothelium was studied after staining with Trypan blue. In a second set of experiments, endothelial viability following this laser procedure was determined using a live cell/dead cell assay. Results: At full thickness cuts, the stromal side of the dissected tissue planes appeared smooth. The average endothelial cell loss in the first set of experiments was 37% (n = 3, range of 12%–71%). In the second set of experiments, the average endothelial loss was 27% (n = 5 and range of 13–35%). Conclusions:The technique of using of the Interlase laser and its coupling device from the endothelial side is promising (with up to 78% of the endothelial cells surviving). Further studies are warranted and will compare commercially available viscoelastics and applantion pressures to optimize endothelial cell survival. This technique may prove to be superior for obtaining thin donor buttons due to the smooth dissection surfaces for the transplantation of corneal endothelium.
Keywords: cornea: endothelium • laser • transplantation