Patients with myopia who have moderate to high astigmatism prefer orthokeratology to soft multifocal contact lenses as a myopia management strategy, according to data reported in Optometry and Vision Science. Although patients treated with both methods reported a preference for orthokeratology for vision and overall use, objective measurements revealed reduced high-contrast and glare visual acuity with this treatment strategy.
Researchers enrolled 30 adults with refractive myopia and astigmatism (1.25-3.50 diopters [D]) in the study and performed corneal tomography measurements. Study participants underwent random assignment to treatment with orthokeratology or soft multifocal contact lenses for 10 days. A washout period of 14 days followed during which participants wore their habitual method of myopic correction. Then, patients switched to the other treatment method for another 10 days. Participants underwent high-contrast, low-contrast, and glare monocular and binocular logarithm of the minimum angle of resolution (logMAR) visual acuity measurements and reported symptoms and lens preferences using the Ranked Symptom Scale and Orthokeratology and Contact Lens Quality of Life surveys. Responses were expressed with a 10-point Likert scale (0, good; 10, poor).
Overall, 17 patients achieved good vision (logMAR, +0.30 or better) with both treatment methods. These participants expressed a preference for orthokeratology lenses for vision and overall use compared with the soft contact lenses (P ≤.007 for both). Participants did, however, report a preference for the soft contact lenses for comfort (Ranked Symptoms Scale: 2.0 vs 5.0; P =.001) and handling (0.0 vs 1.0; P ≤.03 ) compared with orthokeratology.
Toric orthokeratology reduced high-contrast visual acuity by 1 line. Low-contrast visual acuity was reduced by 2 to 2.5 lines from high contrast acuity measurements with each treatment type. Glare acuity produced similar results with high-contrast visual acuity and there was a difference of 1 line between the orthokeratology and soft contact lens treatments (0.00 vs -0.10 logMAR; P ≤.003).
The study authors speculate that visual stability may be responsible for favorable subjective responses despite objective data indicating reduced visual acuity for orthokeratology compared with soft contact lenses.
“When forced to choose between the two lenses, adult participants preferred toric orthokeratology for vision and overall,” the investigators note. “This suggests that patients may prefer the more “stable” blur associated with orthokeratology correction to unstable blur associated with blinking with soft toric multifocal lenses.”
Study limitations include a small sample size, the exclusion of children, and inability to mask examiners.
References:
Tomiyama ES, Richdale R. Clinical outcomes of a randomized trial with contact lenses for astigmatic myopia management. Optom Vis Sci. Published online December 6, 2022. doi:10.1097/OPX.0000000000001969