Myopia
Conditions
Keywords
Myopia progression, Myopia control, Simultaneous vision, Myopic defocus
Brief summary
To determine if the 'Defocus Incorporated Soft Contact' (DISC) lens slows myopia progression in Hong Kong schoolchildren using simultaneous vision approach.
Detailed description
The investigators hypothesize that the natural process of emmetropization in human is regulated by the equilibrium between the opposite hyperopic and myopic defocus. A sharp focus of retinal image (foveal fixation) is fundamental for co-ordination of the equilibrium. The DISC lens is a custom-made multi-zone bifocal soft contact lens which is based on simultaneously provides clear vision and defocus at all viewing distances. It comprises of correcting zones for correcting distant prescription(correction of refractive error, and defocusing zones to incorporate constant myopic defocus for slowing down myopia progression.
Interventions
DEVICEDefocus Incorporated Soft Contact (DISC) lens
Use of simultaneous vision bifocal soft contact lenses with myopic defocus to control the progression of myopia
Sponsors
The Hong Kong Polytechnic University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Investigator)
Eligibility
Sex/Gender
ALL
Age
8 Years to 13 Years
Healthy volunteers
Yes
Inclusion criteria
* Age 8-13 years * Myopia (SE) between -1D to -5D * Astigmatism less than or equal to -1D * Anisometropia: less than or equal to 1.25D * aided VA (monocular): 0.00 log MAR or better * willingness to wear contact lens constantly * availability for follow-up for at least 2.5 years * parents' understanding and acceptance * willing to provide refractive status of grandparents
Exclusion criteria
* Severe ocular or systemic allergies * Taking any medication that might have an impact on contact lens wear or that might influence the outcome of the clinical trial * Ocular or systemic condition that might affect refractive development * Strabismus at distance or near * Prior use of bifocal or progressive lenses * Prior use of rigid gas permeable lenses and Ortho-K lenses
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| The changes of cycloplegic refractive errors | every 6 months for 2 years | Refractive error was measured using Shin-Nippon NVision-K 5001 autorefractor The changes of cycloplegic objective refractive errors between the treatment and the control were compared. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| The changes of axial length | every 6 months for 2 years | Axial length was measured after cycloplegia using IOL Master |
Countries
China
Outcome results
None listed