Femtosecond Laser-Assisted Keratoplasty: Laboratory Studies in Eye Bank Eyes

Purpose: To optimize the surgical technique for performing femtosecond laser-assisted keratoplasty (FLAK) using the IntraLase FS to cut both recipient and donor cornea buttons in eye bank globes. Methods: FLAK was performed in six globes and six corneoscleral buttons for each of the following trephination patterns: top hat, mushroom, tongue-groove, and vertical. Manual trephination was performed as control. The wound integrity was tested in incisions closed with 8 sutures, 8 sutures with fibrin adhesive, and 16 sutures by measuring the intraocular pressure required to produce graft-host wound leakage (IOPL). Light microscopy (LM) and scanning electron microscopy (SEM) were performed to assess cut surface quality and graft-host interface regularity. Results: Mushroom and top hat FLAK had significantly higher IOPL than vertical or manual trephination (p 0.0001) for wounds closed with 16 sutures. There was no difference in IOPL between top hat, mushroom, and tongue-groove FLAK in wounds closed with 8 sutures with fibrin adhesive (p 0.75). LM and SEM demonstrated cut surfaces with good quality and smooth edges. Conclusions: These preliminary studies show that FLAK produces precise trephination cuts of superior wound strength and stability to that of manual trephination. Adjuvant fibrin glue may further improve wound integrity.