Refractive Outcomes after Myoring Implantation

Document Type : Original Article

Authors

1 MSc, Department of Optometry, Faculty of Rehabilitation, Shahid Beheshti University of Medical Science,Tehran, Iran

2 Tutor, Department of Optometry, Faculty of Rehabilitation, Shahid Beheshti University of Medical Science, Tehran, Iran

3 Assistant Professor, Eye Research center, Farabi Eye Hospital, Tehran University of Medical Science, Tehran, Iran

4 PhD Student, Department of Optometry, Faculty of Paramedicine, Mashhad University of Medical Science, Mashhad, Iran

Abstract

Purpose:
To investigate the refractive error and visual acuity before and six months after myoring implantation in patients with keratoconus at Farabi hospital in Tehran, Iran.
Methods:
In this retrospective study, thirty-four eyes of twenty-eight keratoconic patients with mean age of 29 ± 7.41 years who underwent myoring operation and reevaluated after 6 months were recruited. In these patients, best corrected visual acuity (BCVA), refractive outcomes and Pentacam [Oculus GmbH] findings were assessed. All patients had clear central corneas, contact lens intolerance, and a central corneal thickness of more than 360 mm.
Results:
Six months postoperately, the mean BCVA (in LogMAR value) improved significantly from 0.30 ±0.22 to 0.20 ± 0.20 (p=0.006) and the mean spherical refractive error improved from -4.66 D ± 3.76 to -1.48 D ± 3.72 (p<0.001). The mean cylindrical refractive error decreased significantly from -4.27D ±3.15 to -2.18D ±1.63 (p<0.001). In cylindrical refraction, the frequency percent  of  with the rule, oblique and against the rule axes of astigmatism before operation were 21% ,44% and 35%, respectively and  after operation  have changed to 18%, 24%  and 58%, respectively.
Conclusion:
Myoring operation provided significant improvement in BCVA, spherical and cylindrical refractive errors.

Keywords

Main Subjects

References

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Journal of Paramedical Sciences & Rehabilitation
Volume 5, Issue 4
January 2017
Pages 16-22

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