ASTIGMATISM AFTER PENETRATING KERATOPLASTY USING THE KRUMEICH GUIDED TREPHINE SYSTEM

BACKGROUND: The use of a suction trephine during penetrating keratopla sty has the potential to reduce trephination errors and astigmatism af ter suture removal. METHODS: In this study, we evaluated refractive as tigmatism after suture removal in 26 eyes that had penetrating keratop lasty for keratoconus using refraction, keratometry, and videokeratogr aphy. Group I (11 eyes) had manual trephination with an open disposabl e blade of both the donor (8.2 mm) and the recipient (8.0 mm). Group I I (10 eyes) had manual trephination with an open disposable blade of t he donor (8.2 mm) and Krumeich guided trephine system trephination of the recipient (8.0 mm). Group III (5 eyes) had guided trephination of both the donor (8.0 mm) and the recipient (8.0 mm). RESULTS: The guide d trephine groups II and III demonstrated statistically significant le ss refractive cylinder when compared to manual trephination group I (p < .01). The mean keratometric cylinder for group I was 6.50 diopters (D) (range, 1.50 to 9.00 D), for group II was 3.00 D (range, 0.50 to 7 .00 D), and for group III was 2.55 D (range, 0 to 4.00 D). CONCLUSION: The Krumeich guided trephine system produced less keratometric astigm atism than manual trephination after penetrating keratoplasty for kera toconus.