Purpose: To evaluate outcomes from the use of a femtosecond laser to trephine both donor and recipient corneas during penetrating keratoplasty (PK).
Design: Prospective interventional case series.
Methods: Patients were recruited from the cornea clinic of the Singapore National Eye Centre. We used a 10-kHz Femtec (20/10 Perfect Vision, Heidelberg, Germany) femtosecond laser to perform trephination of the donor cornea on an artificial anterior chamber, followed by trephination of the recipient cornea. Trephination cuts were straight and performed 90 degrees to the corneal surface. Tissue bridges were bluntly separated with a Barrett phaco chopper. The donor button was then sutured to the recipient with double continuous sutures, or interrupted sutures if significant host corneal vascularization was present. Postoperatively, visual acuity, refraction, intraocular pressures, and optical coherence tomography (Visante; Carl Zeiss, Jena, Germany) were evaluated.
Results: Eight eyes of eight patients underwent PK for conditions ranging from bullous keratopathy to corneal scarring from herpetic stromal keratitis. Patients were followed up for a mean of 9.5 months. Best-corrected visual acuities of patients with no ocular comorbidity ranged from 20/20 to 20/80. Mean cylindrical refractive error at last review was 2.56 diopters [D] (range, 0.50 to 4.00 D). Tissue bridges were bluntly dissected except for one case that required scissors completion of trephination. No complications were encountered related to use of the Femtec laser.
Conclusion: The Femtec laser reliably trephines both donor and recipient corneas for PK, with good visual outcomes and relatively low degrees of astigmatism.