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Khorrami-Nejad M, Aghili O, Hashemian H, Aghazadeh-Amiri M, Khosravi B. Changes in Corneal Asphericity after MyoRing Implantation in Moderate and Severe Keratoconus. JOVR [Internet]. 2019Oct.24 [cited 2024Apr.18];14(4):428–435. Available from: https://knepublishing.com/index.php/JOVR/article/view/5443

https://doi.org/10.18502/jovr.v14i4.5443

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authors

  • Masoud Khorrami-Nejad

    Masoud Khorrami-Nejad

    Department of Optometry, School of Rehabilitation, Shahid Beheshti University of Medical Sciences, Tehran, Iran
  • Ozra Aghili

    Ozra Aghili

    Eye Research center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran
  • Hesam Hashemian

    Hesam Hashemian

    Eye Research center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran
  • Mohamad Aghazadeh-Amiri

    Mohamad Aghazadeh-Amiri

    Department of Optometry, School of Rehabilitation, Shahid Beheshti University of Medical Sciences, Tehran, Iran
  • Bahram Khosravi

    Bahram Khosravi

    Department of Optometry, School of Rehabilitation, Shahid Beheshti University of Medical Sciences, Tehran, Iran

Published Date

  • Oct 24, 2019
This journal is publishing all the articles under Creative Commons Attribution License CC BY 4.0.

Changes in Corneal Asphericity after MyoRing Implantation in Moderate and Severe Keratoconus

Journal of Ophthalmic and Vision Research (JOVR) / October–December 2019, Volume 14, Issue 4 / Pages 428–435

Abstract

Purpose: To evaluate the effect of MyoRing implantation on corneal asphericity in moderate and severe keratoconus (KCN).


Methods: This cross-sectional observational study comprised 32 eyes of 28 patients with KCN, who had femtosecond-assisted MyoRing corneal implantation. The primary outcome measures were preoperative and six-month postoperative corneal asphericity in 6-, 7-, 8-, 9-, and 10-mm optical zones in the superior, inferior, nasal, temporal, and central areas. The secondary outcome measures included uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refraction, thinnest location value, and keratometry readings.


Results: A significant improvement in the UDVA and CDVA was observed six months after the surgery (P < 0.001) with a significant reduction in the spherical (4.67 diopters (D)) and cylindrical (2.19 D) refractive errors. A significant reduction in the corneal asphericity in all the optical zones and in the superior, inferior, nasal, temporal, and central areas was noted (P < 0.001). The mean thickness at the thinnest location of the cornea decreased from 437.15 ± 30.69 to 422.81 ± 36.91 μm. A significant corneal flattening was seen. The K1, K2, and Km changes were 5.32 D, 7 D, and 6.17 D, respectively (P < 0.001).


Conclusion: MyoRing implantation is effective for improving corneal asphericity in patients with KCN. It allows successful corneal remodeling and provides a significant improvement in UDVA, CDVA, and refractive errors.

Keywords:

Cornea, Corneal Topography, Keratoconus

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