None listed
Conditions
Brief summary
Multifocal contact lenses (MFCLs) have shown promising results in slowing myopia progression in children. However, the underlying mechanism for treating myopia with MFCLs is still uncertain; it is assumed that MFCLs reduce hyperopic defocus in the periphery, inhibit accommodation lag, and improve the amplitude of accommodation in myopes. It has been demonstrated that myopic blur induced by the peripheral portions of these lenses can reduce myopia progression in children by 36.4% and axial elongation by 37.9%. However, the effect of MFCL on the ability of the eye to detect the stimulus properties such as contrast, colour, and motion remains unknown, and it is possible that MFCL impact these functions, which may contribute to its effect in slowing myopia progression. It is assumed that both optical and pharmaceutical treatments use two different mechanisms to reduce myopia progression and combining both interventions (known as combined therapy) may provide better myopia control than one treatment alone (monotherapy). The primary objective of this study is to examine the effects of MFCL alone (monotherapy) and its combination with 0.05 % atropine sulfate eye drops (combined therapy) on a range of basic visual functions (contrast sensitivity, colour, and motion detection), pupil size, and image quality. This research is expected to provide a greater understanding of the effect of MFCL on the blur detection mechanism of the eye and associated visual function changes and the potential mechanisms underlying myopia development and progression. To achieve this, the outcome measurements will be taken twice, first with MiSight contact lenses and then with 0.05 % atropine.
Interventions
This study contains two phases:
Phase one involves fitting one eye with a daily disposable soft multifocal contact lens. After 20 minutes of lens insertion, measurements will be taken.
In the same visit, phase two, one drop of 0.05% of atropine sulfate eye drops will be applied in the same eye wearing contact lenses, taken just once, as one drop in only one eye. The study measurements will be retaken after 30 minutes of eye drop instillation. This visit will take approximately 1 hour and 22 mi
This study contains two phases: Phase one involves fitting one eye with a daily disposable soft multifocal contact lens. After 20 minutes of lens insertion, measurements will be taken. In the same visit, phase two, one drop of 0.05% of atropine sulfate eye drops will be applied in the same eye wearing contact lenses, taken just once, as one drop in only one eye. The study measurements will be retaken after 30 minutes of eye drop instillation. This visit will take approximately 1 hour and 22 minutes. The contact lenses will be removed at the end of phase 2 (after all measurements are completed). Afterward, the participant’s ocular surface will be assessed using a microscopic slit lamp to rule out any possible complications. Treatment device MiSight 1 Day contact lenses prescribed by a registered optometrist to participants with myopia will be worn in one eye for a maximum of 2 hours during the study visit. Treatment Drug 0.05% atropine sulfate eye drops, taken just once, as one drop in one eye. All procedures including drop instillation will be conducted at the School of Optometry and Vision Science, UNSW, and be administered by a Ph.D. candidate under the supervision of Australian registered optometrists.” The study's investigators will only insert the contact lens and install the eye drop during the study visit, so no adherence measurements are required.
Sponsors
Unversity of New South Wales -UNSW
Study design
Allocation
Randomised controlled trial
Intervention model
Single group
Primary purpose
Treatment
Masking
Open (masking not used)
Eligibility
Sex/Gender
All
Age
18 Years to 35 Years
Healthy volunteers
No
Inclusion criteria
• Aged 18-35 years-old with good general health. • An experienced soft contact lens wearer or willing to wear soft contact lenses. • Have a prescription between -0.50 and -4.00D, with less than -1.50D of astigmatism. • Have good ocular health. • Have a ‘normal’ vision, measuring 6/7.5 or better with correction. • Have a normal colour vision • Are willing to attend two study visits. • Have a normal intraocular pressure
Exclusion criteria
• Fitted with rigid gas permeable (RGP) lenses, bifocal or orthokeratology (OK) lenses within 4 weeks prior to study enrolment. • Any eye diseases including inflammation, infection or allergy. • Previous eye surgery within the last 6 months. • Moderate to severe dryness or any disease might affect ocular surface integrity such as Pteryguim. • Using ocular medications or eye drops. • Any other condition which would prevent contact lens wear.
Outcome results
None listed