Korean J Ophthalmol.  2016 Dec;30(6):434-442. 10.3341/kjo.2016.30.6.434.

Effectiveness of Toric Orthokeratology in the Treatment of Patients with Combined Myopia and Astigmatism

• Lyu B
• Hwang KY
• Kim SY
• Kim SY
• Na KS

• KMID: 2374001
• DOI: http://doi.org/10.3341/kjo.2016.30.6.434

Abstract

PURPOSE
The purpose of this multi-institute, single-group clinical trial was to evaluate the effectiveness and safety of toric orthokeratology lenses for the treatment of patients with combined myopia and astigmatism.
METHODS
A total of 44 patients were included in this clinical trial. The patients ranged in age from 7 to 49 years, with myopia of -0.75 to -6.0 diopters (D) and astigmatism of 1.25 to 4.0 D. After excluding 21 subjects, 23 subjects (39 eyes) were analyzed after toric orthokeratology lens use. The subjects underwent ophthalmologic examination after 1 day and 1, 2, 3, and 4 weeks of wearing overnight toric orthokeratology lenses.
RESULTS
A total of 19 subjects (31 eyes) completed the trial after five subjects (eight eyes) dropped out. In the patients who completed the study by wearing lenses for 4 weeks, the myopic refractive error decreased significantly by 2.60 ± 2.21 D (p < 0.001), from -3.65 ± 1.62 to -1.05 ± 1.64 D. The astigmatic refractive error were also significantly decreased by 0.63 ± 0.98 D (p = 0.001), from 2.07 ± 0.83 to 1.44 ± 0.99 D. The mean uncorrected and corrected visual acuities before wearing the lenses were 2.14 ± 0.80 logarithm of the logMAR (logMAR) and 0.05 ± 0.13 logMAR, respectively, which changed to 0.12 ± 0.30 logarithm of the logMAR (p < 0.001) and 0.01 ± 0.04 logMAR (p = 0.156) after 4 weeks. No serious adverse reactions were reported during the clinical trial.
CONCLUSIONS
Our results suggest that toric orthokeratology is an effective and safe treatment for correcting visual acuity in patients with combined myopia and astigmatism.

Keyword

Astigmatism; Contact lenses; Myopia; Orthokeratologic procedures; Refraction

MeSH Terms

Adolescent
Adult
Astigmatism/complications/diagnosis/*therapy
Child
Cornea/*diagnostic imaging
Female
Humans
Male
Middle Aged
Myopia/complications/diagnosis/*therapy
Orthokeratologic Procedures/*methods
Slit Lamp Microscopy
Treatment Outcome
*Visual Acuity
Young Adult

Figure

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  Fig. 1 Numbers of subjects recruited for the study and who dropped out. The reasons for exclusion and drop-out are described. TBUT = tear break-up time.

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  Fig. 2 Scattergram showing subject distribution according to myopic refractive error at the time of screening and at the end of the study.

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  Fig. 3 Scattergram showing subject distribution according to astigmatic refractive error at the time of screening and at the end of the study.

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  Fig. 4 Typical topographic pattern of corneal astigmatism of subjects at screening (A) and at the end of the study (B). The average corneal astigmatism of subjects decreased from 1.9 to 1.6 diopters. OD = right eye.

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