Astigmatic outcomes in myopic wavefront-guided laser in situ keratomileusis versus wavefront-guided photorefractive keratectomy using vector analysis.

PURPOSE: To compare astigmatic outcomes between eyes having wavefront-guided laser in situ keratomileusis (LASIK) and eyes having wavefront-guided photorefractive keratectomy (PRK).

SETTING: Byers Eye Institute, Stanford University School of Medicine, Palo Alto, California, USA.

DESIGN: Prospective randomized case series.

METHODS: Patients had refractive surgery, with one eye treated with LASIK and the other treated with PRK. Eyes were randomized according to ocular dominance. Astigmatism vectors were evaluated using the Alpins vector analysis of astigmatism.

RESULTS: Thirty-four patients (68 eyes) had vector analysis; the LASIK and PRK groups had similar target-induced astigmatism vectors (P = 0.75), surgically induced astigmatism vectors (P = 0.86), difference vectors (P = 1.0), indices of success (P = 0.4), correction indices (P = 0.28), and flattening indices (P = 0.5).

CONCLUSION: Based on Alpins vector analysis of astigmatism, there were no statistically significant differences between eyes that had LASIK and eyes that had PRK.