Corneal endothelial viability after femtosecond laser preparation of posterior lamellar discs for Descemet-stripping endothelial keratoplasty

Purpose: To evaluate the feasibility of the femtosecond (FS) laser in preparation of posterior lamellar discs (PLDs) and to study the effect on endothelial cell (EC) viability for Descernet-stripping endothelial keratoplasty. Methods: Fourteen human donor bulbi unsuitable for transplantation were used. A horizontal lamellar cut was prepared in the donor cornea with an FS laser by using a raster and/or a spiral spot pattern. The control group consisted of the paired cornea of the same donor. EC density was evaluated before and after preservation in organ culture. The PLD was stripped from the anterior part by using either a forceps or a blunt dissection technique. The damage to the endothelium was evaluated. Results: EC loss after organ storage was not statistically significant between the FS cornea group and the control group in the 15-(7.7% 6.9% and 8.9% +/- 8.1%, respectively; P = 0.78) and 30-kHz (4.3% +/- 4.0% and 3.7% +/- 3.6%, respectively; P = 0.75) group. There was no significant effect of laser frequency (15 vs. 3 0 kHz) on EC loss (7.7% vs. 4.3%, P = 0.25). Dissection by using a forceps stripping technique resulted in higher EC loss than that with a blunt dissection technique (13.0% vs. 6.5%, P = 0.03). Conclusions: EC loss after FS laser lamellar cutting is not dependent on the frequency (ie, energy level) of the laser. A blunt dissection technique of PLDs resulted in acceptable EC loss and supports the clinical use of the FS laser for the preparation of PLDs.