Promising results using the Hanna Corneal Trephine System in penetrating keratoplasty

To evaluate the outcome of penetrating keratoplasties using the Hanna Corneal Trephine System.

Fifty-five patients out of 70, who had penetrating keratoplasty performed by a single surgeon (KHO), from 1995 to 2001, were reviewed in 2002, at Department of Ophthalmology, Hospital of Hilleroed, Denmark. The reviews were performed by a single observer (NJ). All donor corneas were trephined from the epithelial side. Visual acuity, refraction, corneal astigmatism, and graft survival were main outcome measures.

Seventy-two percent of the patients achieved a visual acuity > or =0.5. In major subgroups, that is, Fuchs endothelial dystrophy, secondary endothelial dystrophy, and keratoconus, a best corrected visual acuity of > or =0.5 was achieved in 57, 67, and 100%, respectively. The mean (+/-SD) postoperative spherical refraction was +0.84 D (+/-3.72), whereas mean keratometric and refractive astigmatism were -3.24 D (+/-1.51) and -3.06 D (+/-1.95), respectively. The overall graft survival rate was 96.7% after 2 years and 81.2% after 5 years. At least 90% of all patients were content with the result and course of the operation.

The best corrected visual acuity was better, and the degree of astigmatism was less compared to previously reported studies. We suggest that these findings can be partly explained by the operative technique, that is, cutting the donor and the recipient cornea from the epithelial side by the use of an artificial chamber.