INTRAOPERATIVE CAUTERIZATION OF THE CORNEA CAN REDUCE POSTKERATOPLASTY REFRACTIVE ERROR IN PATIENTS WITH KERATOCONUS

Objective: This study aimed to evaluate the effect of intraoperative c orneal cauterization on the postkeratoplasty refraction of patients wi th keratoconus. Design: A randomized clinical trial. Participants: Thi rty eyes of 29 patients with keratoconus undergoing standard penetrati ng keratoplasty by the same surgeon were evaluated (MB). Intervention: Standard penetrating keratoplasty included the use of an 8.0-mm donor button sutured into a 7.5-mm recipient bed by means of two running 10 -0 nylon sutures with 16 bites each. Before trephination of the recipi ent bed, superficial cauterization causing tissue shrinkage was applie d to a 6-mm central area of the cornea of only 15 eyes (group A). The remaining 15 eyes (group B) did not undergo intraoperative cauterizati on. Before surgery, 6 months, and 13 months after surgery, a complete ophthalmologic examination was performed on each patient, including un corrected and best-corrected visual acuity, refraction, keratometry, c omputerized corneal topography, as well as A-scan contact ultrasonogra phy. Main Outcome Measures: Postkeratoplasty refractive error was meas ured. Results: Both 6 months (sutures still in place) and 13 months (s uture removal performed in all patients) after surgery, the average sp herical equivalent was significantly less myopic in the patients under going cauterization. At 6 months, it was +1.72 diopters (D) +/- 1.13 D in group A and -3.16 D +/- 2.84 D in group B; at 13 months, it was +0 .09 D 1.52 D in group A and -3.89 D +/- 3.01 D in group B. The average keratometric astigmatism also was significantly lower in group A than in group B both at 6 (2.5 D +/- 1.6 D vs. 4.1 D +/- 2.3 D) and 13 mon ths (2.7 D +/- 1.5 D vs. 4.4 D +/- 2.4 D) after surgery. Conclusion: C auterization of the central cornea improves the postkeratoplasty refra ctive results of patients with keratoconus.