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

Abstract

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 (IOP_L). 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 IOP_L than vertical or manual trephination (p < 0.0001) for wounds closed with 16 sutures. There was no difference in IOP_L 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.

Keywords:

• femtosecond laser
• fibrin adhesive
• penetrating keratoplasty