Comparison of femtosecond laser small-incision lenticule extraction and laser-assisted subepithelial keratectomy to correct myopic astigmatism.

Abstract

PURPOSE:

To compare the efficacy of correcting myopic astigmatism with femtosecond laser small-incision lenticule extraction (SMILE, Carl Zeiss Meditec AG) versus laser-assisted subepithelial keratectomy (LASEK).

SETTING:

The study was conducted at the Ophthalmology Department, Eye and ENT Hospital, Shanghai, China.

DESIGN:

A retrospective, cross-sectional study.

METHODS:

This study included patients who underwent small-incision lenticule extraction or LASEK for the correction of myopia and myopic astigmatism. Preoperative and 6-month postoperative astigmatism values were analyzed. The efficacies of the 2 surgeries to correct astigmatism were compared.

RESULTS:

A total of 180 right eyes of 180 patients (small-incision lenticule extraction: n = 113, LASEK: n = 67) were included. No significant difference was found between the 2 groups in the preoperative astigmatism (small-incision lenticule extraction: 1.16 ± 0.85D, LASEK: 1.16 ± 0.83D, P > .05) or the postoperative astigmatism (small-incision lenticule extraction: 0.35 ± 0.37D; LASEK: 0.31 ± 0.42D, P > .05), determined by manifest refraction. No significant difference was found between the 2 groups in surgically induced astigmatism vector (small-incision lenticule extraction: 1.13 ± 0.83D, LASEK: 1.01 ± 0.65D, P > .05). The correction index was higher for the small-incision lenticule extraction group (1.05 ± 0.53) than for the LASEK group (0.95 ± 0.21, P = .045). The postoperative astigmatism was significantly higher for the small-incision lenticule extraction group when the preoperative astigmatism was 1.0 D or less (small-incision lenticule extraction: 0.26 ± 0.30D, LASEK: 0.12 ± 0.20D, P = .007) and lower for the small-incision lenticule extraction group when the preoperative astigmatism was more than 2.0 D (small-incision lenticule extraction: 0.48 ± 0.37D, LASEK: 0.89 ± 0.46D, P = .002).

CONCLUSIONS:

An adjustment of nomograms for correcting low astigmatism (≤1.0 D) by small-incision lenticule extraction is suggested due to the tendency toward overcorrection, whereas a nomogram adjustment for tissue-saving ablation profile is needed for the correction of high astigmatism (>2.0 D) by LASEK due to the tendency toward undercorrection.

FINANCIAL DISCLOSURE:

The authors declare that they have no competing financial interests.

• Authors: Yishan Qian, Jia Huang, Xingtao Zhou, Yutung Wang
• Journal: Journal of cataract and refractive surgery (J Cataract Refract Surg) Vol. 41 Issue 11 Pg. 2476-86 (Nov 2015) ISSN: 1873-4502 [Electronic] United States
• PMID: 26703499 (Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2015 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Topics

• Adolescent
• Adult
• Astigmatism (physiopathology, surgery)
• Corneal Stroma (surgery)
• Corneal Topography
• Cross-Sectional Studies
• Female
• Humans
• Keratectomy, Subepithelial, Laser-Assisted (methods)
• Lasers, Excimer (therapeutic use)
• Male
• Microsurgery (methods)
• Middle Aged
• Myopia (physiopathology, surgery)
• Nomograms
• Postoperative Period
• Preoperative Period
• Refraction, Ocular (physiology)
• Retrospective Studies
• Visual Acuity (physiology)
• Young Adult