Abstract
Purpose: :
When precut with a 30 kHz femtosecond laser for Descemet Stripping Automated Endothelial Keratoplasty (DSAEK), endothelial grafts were shown to provide rough interfaces. We compared stromal interfaces of endothelial grafts obtained with 60 kHz and 150 kHz femtosecond lasers.
Methods: :
Six experimental corneas (BFY, France) were prepared using a femtosecond laser (Intralase AMO). A double path precut procedure was performed with laser60 (60 kHz) on corneas 1,2,3 and with laser150 (150 kHz) on corneas 4,5,6. Laser parameters were set to deliver the lowest energy required to achieve a complete precut. Stromal interfaces of the grafts were observed with a scanning electron microscope (SEM).
Results: :
With laser60 set at 2.4kJ/500µm/spot-line 4:4, an efficient precut was obtained on corneas 2, 3 whereas lamellar bridges persisted in the 3mm central area of the graft from cornea 1. With laser150 set at 1.05kJ/500µm/spot-line 2:2, an optimal precut was achieved for all corneas. On SEM, laser150 failed to generate smoother interfaces when compared to laser60 despite settings allowing closer spots.
Conclusions: :
Femtosecond laser is promising to precut grafts for DSAEK. The current 60 kHz and 150 kHz Intralase cutting profiles are efficient for graft precutting and less energy is delivered with laser150. Additional works are needed to further improve the smoothness of graft’s interfaces.
Keywords: cornea: clinical science • laser