Dataset Information

Corneal curvature, asphericity, and aberrations after transepithelial photorefractive keratectomy and femtosecond laser-assisted in situ keratomileusis for myopia: A prospective comparative study.

ABSTRACT:

Purpose

We aimed to compare transepithelial photorefractive keratectomy (TPRK) and femtosecond laser-assisted in situ keratomileusis (FS-LASIK) for myopia treatment by analyzing corneal curvature, asphericity (Q-value), and corneal aberration.

Methods

Corneal topography was measured before and 6 months after the TPRK or FS-LASIK surgery. We measured and compared corneal curvature (sagittal curvature in the 1- to 7-mm zones), change in keratometric measurements (Kmpost - Kmpre, ?K), Q-values (from the vertex of the 6-, 7-, 8-, and 9-mm zones), higher-order aberration (HOA), vertical and horizontal trefoil (Z3^-3 and Z3³), vertical and horizontal coma (Z3^-1 and Z3¹), and spherical aberration (Z4⁰) between the two surgery groups.

Results

The sagittal curvature ? K in the 1-mm zone after TPRK was significantly higher than after FS-LASIK. The ? K/?SE (?SE [spherical equivalent] = SEpre - SEpost) ratio in the 1- to 4-mm diameter zones was significantly higher after TPRK than after FS-LASIK. The preoperative Q-values of the 6- and 7-mm zones did not differ between the treatment groups, but postoperative values were significantly higher following FS-LASIK than following TPRK. HOA, Z4⁰, and Z3^-1 were all significantly higher after surgery in both groups. Postoperative Z3^-3 was significantly higher following TPRK but not following FS-LASIK. There were no postoperative differences in aberrations in either group; however, the change in HOA and Z3^-1 was significantly greater following FS-LASIK.

Conclusion

TPRK changes the corneal curvature to a greater extent and the visual quality (Q-value, aberrations) to a lesser extent than FS-LASIK.

SUBMITTER: Zhang YL

PROVIDER: S-EPMC7856998 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Publications

Corneal curvature, asphericity, and aberrations after transepithelial photorefractive keratectomy and femtosecond laser-assisted <i>in situ</i> keratomileusis for myopia: A prospective comparative study.

Zhang Ya-Li YL Xu Xiang-Hui XH Cao Li-Jun LJ Liu Lei L

Indian journal of ophthalmology 20201201 12

<h4>Purpose</h4>We aimed to compare transepithelial photorefractive keratectomy (TPRK) and femtosecond laser-assisted in situ keratomileusis (FS-LASIK) for myopia treatment by analyzing corneal curvature, asphericity (Q-value), and corneal aberration.<h4>Methods</h4>Corneal topography was measured before and 6 months after the TPRK or FS-LASIK surgery. We measured and compared corneal curvature (sagittal curvature in the 1- to 7-mm zones), change in keratometric measurements (Kmpost - Kmpre, ΔK) ...[more]

PMID: 33229675

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