Tampa Trephine Penetrating Keratoplasty

The Tampa Trephine penetrating keratoplasty technique (TTPK) provides a 7.0 mm corneal donor button with six rectangular tabs of Bowman’s layer and anterior stroma, 50 microns in thickness, which are inserted into the recipient corneal stroma beneath Bowman’s layer. TTPK offers the hypothetical advantages over standard penetrating keratoplasty of a more stable donor-host interface, the presence of fewer sutures (12 interrupted), lower astigmatism, a shorter visual acuity recovery period, and additional tectonic support in thin recipient beds. This article reports the results from the first 35 patients operated on within a four month follow-up period. The patients in this study were submitted to TTPK and evaluated postoperatively at 1, 7, and 15 days, as well as 1,2, 3, and 4 months. Retrospective evaluations included visual acuity, computerized corneal topography, ultrasonic pachymetry, slit lamp examination, and intraocular pressure. The tab presence induced a clinically stable donor-host interface by four months postoperatively. Early suture removal accomplished in nine cases in the postoperative time frame between 110 and 145 days reflected in minimal astigmatism only in three sutureless corneas. A myopic postoperative sphere was usually observed, especially when early complete suture removal was accomplished. Early postoperative complications included transient donor epithelial defects and corneal edema, inadequate wound closure, wound dehiscence, superficial neovascularization directed towards the tabs, epithelial inclusion in the stromal pocket, and contamination of the donor button. Late complications included one primary graft failure, one endothelial graft rejection, and one crystalline keratopathy.