Active cyclotorsion error correction during LASIK for myopia and myopic astigmatism with the NIDEK EC-5000 CX III laser.

PURPOSE To investigate the predictability and accuracy of active cyclotorsion compensation during LASIK for myopia with astigmatism. METHODS Fifty-two eyes of 26 patients were divided into two groups; one group (30 eyes) underwent primary LASIK with torsion error correction (TEC [TEC group]) and 22 eyes underwent LASIK without TEC (control group). The NIDEK EC-5000 CX III excimer laser was used for all treatments. All eyes were targeted for emmetropia. Manifest refraction spherical equivalent (MRSE), refractive outcomes, and dispersion and predictability of manifest refractive cylinder were compared between the TEC and control groups. A P value < .01 was considered statistically significant. All outcomes are reported at 3 months postoperatively. RESULTS Statistically significantly lower cylinder dispersion and mean manifest refractive cylinder postoperatively were demonstrated in the TEC group (P < .01). Final refractive cylinder for the TEC group was -0.21 +/- 0.16 diopters (D) (range: -0.62 to 0.00 D) and -0.56 +/- 0.34 D (range: -1.25 to 0.00 D) for the control group. No statistically significant differences in mean MRSE or safety (defined as a loss of 2 or more lines of best spectacle-corrected visual acuity) was noted between groups. CONCLUSIONS LASIK with active cyclotorsion error correction increases the accuracy of cylinder correction.