Monthly Replacement Orthokeratology for Myopia Control in Existing Lens Wearers

The Hong Kong Polytechnic University80 enrolled

Overview

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.

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.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

SINGLE

Enrollment

Conditions

Myopic Progression

Interventions

orthokeratologyDEVICE

Nightly wear of orthokeratology lenses to correct vision in the daytime

Menicon Progent A+BDEVICE

Menicon Progent A+B is a commercially available protein remover for rigid lenses. It has received FDA clearance and been launched in Hong Kong for over a decade. The product contains two separate sterile solutions, one with sodium hypochlorite and the other with potassium bromide. By mixing the two solutions in a special vial, it can clean and remove protein deposits on the lenses. Parents of subjects assigned to use weekly protein remover will be required to soak the cleansed lenses in the solution mixture for not more than 30 mins every week. All lenses must be rinsed thoroughly with saline and cleansed with daily cleaner again before daily disinfection.

Eligibility

Sex: ALLMin age: 8 YearsMax age: 15 YearsHealthy volunteers:

Medical Language ↔ Plain English

Inclusion Criteria: * 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 Exclusion Criteria: * 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

Locations (1)

School of Optometry, The Hong Kong Polytechnic University

Kowloon, Hong Kong

Outcomes

Primary Outcomes

Axial elongation in 2 years

Cycloplegic examination of the eyeball length using IOLMaster every 6 monthly

Time frame: 2 years

Back Surface Lens Deposits

Surface deposits will be graded using a 4-point scale: 0=no deposit; 1=mild; 2=moderate; 3=severe

Time frame: Every month up to 12 months

Secondary Outcomes

Number of participants with serious adverse effects in 2 years

Number of subjects with serious adverse effects of the cornea, the palpebral, bulbar and tarsal conjunctiva in 2 years

Time frame: 2 years

Data from ClinicalTrials.gov

This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.