Evaluation of new phakic intraocular lenses and materials

AcrySof cachet phakic intraocular lens in myopic patients: visual performance, wavefront error, and lens position

PURPOSE

To evaluate visual and aberrometric outcomes and position of the AcrySof Cachet (Alcon Laboratories Inc) angle-supported phakic intraocular lens (PIOL) for correction of myopia in adults.

METHODS

This prospective study included 36 consecutive eyes with moderate to high myopia in which an AcrySof Cachet PIOL was implanted to minimize refractive error. Follow-up was up to 1 year.

RESULTS

Mean manifest spherical equivalent refraction reduced significantly from -14.90 ± 0.90 diopters (D) to -0.29 ± 0.30 D at 1 month and remained stable at 1 year (P<.001). Mean uncorrected distance visual acuity was >0.1 logMAR (20/20 Snellen) in 56% of patients and >0.3 logMAR (20/25 Snellen) in 100% of patients. Corrected distance visual acuity was >0.1 logMAR (20/20 Snellen) in 78% of patients and >0.3 logMAR (20/25 Snellen) in 100% of patients. Mean endothelium-PIOL distance and mean PIOL-crystalline distance were within recommended values at all postoperative evaluations. Statistically significant variations for these variables were not observed. Anterior chamber depth, safety center distance, and vault center distance showed significant reduction after accommodation (P<.01). Anterior chamber depth and safety center distance significantly increased after pupil dilation (P<.01). Mean percentage of endothelial cell loss was 4.04% at 1 year. The root-mean-square of total higher order aberrations and spherical, coma, and trefoil aberrations did not change significantly from pre- to postoperatively.

CONCLUSIONS

The AcrySof Cachet PIOL was effective in the correction of moderate to high myopia and provided excellent visual performance with no modification of physiologic ocular wavefront error. Adequate distance from the cornea and crystalline lens was maintained with no significant change during follow-up and under different environmental conditions.

Basic knowledge of refractive surgery: correction of refractive errors using modern surgical procedures

INTRODUCTION

Refractive ophthalmic surgery allows refractive errors to be corrected permanently in a safe, effective, and reliable way with few complications.

METHODS

Selective literature review with special reference to the guidelines of the German Commission for Refractive Surgery.

RESULTS

With a total of almost 18 million treatments performed to date, laser in-situ keratomileusis (LASIK) is the most commonly used refractive surgical procedure worldwide. Alternatives to LASIK include surface ablation procedures (PRK, LASEK, Epi-LASIK) and phakic intraocular lens implantation. If ocular accommodation is lost, removal of the crystalline lens and implantation of modern multifocal intraocular lenses (refractive lens exchange) provide an alternative means of correcting myopia, hyperopia and presbyopia.

DISCUSSION

The treatment effect is maximized and complications kept to a minimum if strict inclusion criteria are applied and a high technical standard maintained during the procedure.