This prospective study found that a new penetrating keratoplasty (PK) procedure using a femtosecond laser to create anvil-shaped profiles and a diode laser for wound sealing may improve the outcomes of corneal surgery in a variety of pathologic conditions.
The limitations of traditional PK include high astigmatism and endothelial cell loss. This study suggests that newer technology can be used as an adjuvant to the procedure to improve outcomes. More studies with longer follow-up will be needed, however, to substantiate these findings.
The authors report on their experience with laser-assisted PK combining the use of a femtosecond laser to trephine the host and donor graft in an anvil-shaped profile and a diode laser to weld the surgical wound. The anvil profile was designed to create a more structurally stable and predictable wound configuration to achieve faster vision recovery and higher optical quality compared with conventional blade trephination and other more common laser-cut patterns. Moreover, according to the authors, this shape provides a wide contact surface between the donor and recipient corneas, allowing for an effective application of the laser-welding procedure.
They performed the procedure in 22 patients (24 eyes) with granular dystrophy, final-stage keratoconus, post-herpetic leukoma or corneal scars. They used a femtosecond laser (iFS150, Intralase FS Laser, Abbott Medical Optics) to create anvil-profiled cuts in both donor and recipient corneas, then secured the donor cornea to the recipient bed with four cardinal sutures that were later removed after completion of a 16-running 10-0 nylon suture. Diode laser welding was then performed using a near infrared diode laser. There were no intraoperative complications or adverse events.
Mean best corrected vision improved to 0.13 ± 0.16 logMAR at 12 months, with little endothelial cell loss. Furthermore, mean postoperative astigmatism was reasonable even at one month (3.6 D) and remained so at 12 months (2.73 D).
From early in the postoperative period (one month) onward, a well-formed wound scar and smooth tissue transition were observed in almost all patients. Also, the donor–host interface was well-apposed and regular in all cases at six months, as confirmed by Visante OCT analysis. Two patients experienced epithelial rejection, which was managed successfully with systemic and local corticosteroids.