Ocular optical aberrations after photorefractive keratectomy for myopia and myopic astigmatism.

Abstract

To study the effects of photorefractive keratectomy on ocular optical aberrations and to establish correlations with glare vision and low-contrast vision. Preoperative ocular aberroscopy of 15 eyes undergoing photorefractive keratectomy was compared with aberroscopy at 3 months postoperatively by means of a newly developed automated aberroscope of the Tscherning type. The correlation of the wavefront errors with best spectacle-corrected visual acuity, low-contrast visual acuity, and visual acuity under glare conditions was analyzed. In any individual treated, the total wavefront error increased. On average, the total wavefront error increased by a factor of 17.65; this increase was highly statistically significant (P = .001). Also, the correlation with best-corrected visual acuity, low-contrast visual acuity, and glare visual acuity was statistically significant (P = .02, P = .001, and P = .03, respectively). The increase in ocular aberrations was significantly related with the virtual pupil size. Photorefractive keratectomy increases the ocular aberrations, impairing the visual performance of the eyes treated. In detail, scotopic visual measures such as low-contrast visual acuity and glare visual acuity suffer most from the myopia correction. Aberroscopy-guided photorefractive keratectomy may avoid such effects.