Monthly Replacement Orthokeratology for Myopia Control in Existing Lens Wearers
- Conditions
- Myopic Progression
- Interventions
- Device: orthokeratologyDevice: Menicon Progent A+B
- Registration Number
- NCT04295707
- Lead Sponsor
- The Hong Kong Polytechnic University
- Brief Summary
The two-year prospective study aims at investigating the benefits of frequent replacement (monthly) orthokeratology lenses in myopia control in terms of effectiveness in control and prevention of ocular complications. The secondary objective will be investigating the use of weekly protein removal system in monthly replacement modality orthokeratology lenses on surface deposit.
- Detailed Description
This is a two-year randomized trial. Existing orthokeratology lens wearers (aged 8-13 years), who have completed a 2-year myopia control using orthokeratology, will be recruited and monitored for another two years. Eligible subjects will be randomly assigned to monthly or yearly replacement modality. Axial elongation and ocular conditions will be compared between the monthly and yearly replacement groups.
Subjects on monthly replacement lenses will be randomly assigned to normal cleaning and intensive cleaning groups. Subjects in normal cleaning group will be provided with complimentary contact lenses solutions for daily cleaning and disinfection. In addition to the daily procedures for lens case, subjects in the intensive cleaning group will be required to perform weekly protein removal. All subjects on yearly replacement lenses will be required to performed intensive cleaning such that they will follow normal daily cleaning and disinfection as well as weekly protein removal.
Recruitment & Eligibility
- Status
- UNKNOWN
- Sex
- All
- Target Recruitment
- 80
- Aged 8-15 years
- Have completed a two-year myopia control study using ortho-k
- Normal ocular and general condition and not on medication which may contraindicate ortho-k lens wear
- Pre-ortho-k refractive sphere between -0.75 to -4.00 DS, refractive cylinder ≤ -1.50 DC and anisometropia ≤ -1.00 D
- Best correctable vision better than 0.08 logMAR in the worse eye
- Normal binocular function and accommodative status
- Strabismus at distance or near
- Contraindication for ortho-k lens wear
- Prior history of ocular surgery, trauma, or chronic ocular disease
- Systemic or ocular conditions that may interfere refractive development
- Systemic or ocular conditions that may interfere tear quality and contact lens wear
- Poor response to the use of study lenses
- Poor compliance to test procedures
- Poor compliance to the use of ortho-k lenses (e.g. use of solution, use of lenses)
- Poor compliance to follow-up schedule
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description Monthly replacement orthokeratology without protein removal orthokeratology Subjects will be required to perform daily cleaning for the monthly replacement orthokeratology lenses Monthly replacement lenses with weekly protein removal Menicon Progent A+B Subjects will be required to perform both daily cleaning and weekly protein removal for the monthly replacement orthokeratology lenses Yearly replacement lenses with weekly protein removal Menicon Progent A+B Subjects will be prescribed with orthokeratology lenses which will be replaced at least every 12 months during the study period. They will be required to perform both daily cleaning and weekly protein removal for their lenses. Monthly replacement lenses with weekly protein removal orthokeratology Subjects will be required to perform both daily cleaning and weekly protein removal for the monthly replacement orthokeratology lenses Yearly replacement lenses with weekly protein removal orthokeratology Subjects will be prescribed with orthokeratology lenses which will be replaced at least every 12 months during the study period. They will be required to perform both daily cleaning and weekly protein removal for their lenses.
- Primary Outcome Measures
Name Time Method Axial elongation in 2 years 2 years Cycloplegic examination of the eyeball length using IOLMaster every 6 monthly
Back Surface Lens Deposits Every month up to 12 months Surface deposits will be graded using a 4-point scale: 0=no deposit; 1=mild; 2=moderate; 3=severe
- Secondary Outcome Measures
Name Time Method Number of participants with serious adverse effects in 2 years 2 years Number of subjects with serious adverse effects of the cornea, the palpebral, bulbar and tarsal conjunctiva in 2 years
Trial Locations
- Locations (1)
School of Optometry, The Hong Kong Polytechnic University
🇭🇰Kowloon, Hong Kong