Learning curve for radial keratotomy

I prospectively evaluated my own learning curve for radial keratotomy (RK) by comparing the results achieved in two groups: 20 consecutive eyes on which I performed RK without having had previous experience with the procedure (group 1); and 20 other eyes, matched for age, sex, and preoperative refractive error, on which I performed RK after I had performed the procedure 250 times (group 2). Although there were nine microperforations in group 1 and none in group 2, the postoperative refractions and uncorrected visual acuities were similar in both groups. Since the microperforations had no adverse effect on the visual results, it is reasonable to conclude that there was, in effect, no learning curve involved in my experience with RK.