Wavefront-guided Treatment of Symptomatic Eyes Using the LADAR6000 Excimer Laser

PURPOSE

To evaluate the clinical results of wavefront-guided customized treatment of eyes that underwent previous keratorefractive surgery with clinically significant visual symptoms related to the presence of higher order aberrations, with or without defocus/astigmatism.

METHODS

Twenty-eight consecutive eyes of 19 symptomatic patients underwent wavefront-guided custom photorefractive keratectomy (PRK with mitomycin C) to correct low and high order aberrations, using the LADARVision platform. All eyes had manifest refractive spherical equivalent (MRSE) error from 0.00 to –4.25 diopters (D), and high order aberrations root-mean-square (RMS) values >0.80 µm for a 6.0-mm measurement diameter (mean: 1.18 µm). Eyes were examined at 1, 3, and 6 months postoperatively. Uncorrected (UCVA) and best spectacle-corrected visual acuity (BSCVA), MRSE, wavefront measurement of high order aberrations, and patient subjective evaluation were the parameters used to assess the treatment.

RESULTS

Six months after treatment, all 28 eyes had an improvement in UCVA compared to preoperative values. Seventeen (60.7%) eyes gained lines of BSCVA (1 to 3 lines) whereas 1 eye lost 1 line. Although the amount of positive defocus was intentionally and empirically undercorrected in this study, MRSE was slightly hyperopic (mean +0.65 D, range: –0.25 to +1.75 D). All eyes showed a reduction in pre-existing high order aberrations, with a mean reduction of 47% (0.62 µm). Spherical aberration reduced the most (mean 60%), coma was reduced by a mean 29%, and all other terms were reduced by a mean 42% compared to preoperative values. Subjectively, all patients but 1 (both eyes treated) noticed a reduction in their pre-existing visual symptoms. Overall, the treatment was considered satisfactory by the patients in terms of visual quality gain.

CONCLUSIONS

This series of consecutive treatments of symptomatic eyes indicates wavefront-guided custom ablation is an effective surgical option to reduce visually impairing high order aberrations and related visual symptoms. To avoid the resulting hyperopic shift, some significant nomogram adjustments are necessary, most often when pre-existing positive spherical aberration is present. [J Refract Surg. 2006;22:S983-S989.]

AUTHORS

From Carones Ophthalmology Center, Milan, Italy.

Dr Carones is a paid consultant for Alcon Laboratories Inc. The remaining authors do not have any financial or proprietary interest in the materials presented herein.

Correspondence: Francesco Carones, MD, Carones Ophthalmology Center, Via Pietro Mascagni 20 - 20122 Milan, Italy. Tel: 39 02 7631 8174; Fax: 39 02 7631 8506; E-mail: fcarones@carones.com