Clinical trial NCT04293328: Monthly Replacement Orthokeratology for Myopia Control in Young Children
Official title: Accrued Effect of Orthokeratology for Myopia Control in Children and the Effectiveness of Myopia Control Using an Innovative Orthokeratology Modality. Experiment 2. Effect in New Ortho-k Wearers
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: NA
Conditions: Myopic Progression
Keywords: Myopia progression
Orthokeratology
Replacement modality
Surface deposits
Lead sponsor: The Hong Kong Polytechnic University
Sponsor class: OTHER
Collaborators: name: Menicon Co., Ltd.
First posted: 2020-03-03
Enrollment: 30
Sex: ALL
Minimum age (years): 6
Maximum age (years): 10
Standard ages: CHILD
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: All subjects will be prescribed with monthly replacement orthokeratology for a period of 12 months. They will be randomly assigned to normal cleaning and intensive cleaning groups on 1:1 basis. All subjects follow the same daily cleaning procedures and subjects in intensive cleaning group will be required to perform weekly protein removal in addition to the daily routine.
Primary purpose: TREATMENT

Brief summary: The two-year prospective study aims at investigating frequently replacement effect on myopia control in young children, and the use of weekly protein removal system in monthly replacement modality orthokeratology lenses on surface deposit.

Detailed description: In this two-year prospective study, low myopic children, aged 6-8 years, who have no prior experience in contact lens wear and myopia control treatment will be recruited. They will be prescribed with monthly replacement orthokeratology lenses for a period of one year. Axial elongation and ocular conditions during the study will be determined. Subjects 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.

Eligibility criteria: Inclusion Criteria:

* Aged 6-10 years
* Normal ocular and general condition and not on medication which may contraindicate ortho-k lens wear
* Refractive sphere between -0.75 to -4.00 D, refractive cylinder ≤ -1.50 D and anisometropia ≤ -1.00 D
* Best correctable vision better than 0.08 logMAR in the worse eye
* Normal binocular function and accommodative status
* No prior experience in contact lens wear and myopia control treatment

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

Primary outcomes:
measure: Axial elongation in 2 years
timeFrame: 12 months
measure: Changes in Back Surface Lens Deposits
timeFrame: Every month up to 24 months
Secondary outcomes:
measure: Number of participants with serious adverse effects in 2 years
timeFrame: 24 months
Other outcomes:
Locations:
city: Kowloon
country: Hong Kong
facility: School of Optometry, The Hong Kong Polytechnic University
Study officials:
affiliation: The Hong Kong Polytechnic University
name: Pauline Cho, PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Lee YC, Wang JH, Chiu CJ. Effect of Orthokeratology on myopia progression: twelve-year results of a retrospective cohort study. BMC Ophthalmol. 2017 Dec 8;17(1):243. doi: 10.1186/s12886-017-0639-4.
citation: Stapleton F, Carnt N. Contact lens-related microbial keratitis: how have epidemiology and genetics helped us with pathogenesis and prophylaxis. Eye (Lond). 2012 Feb;26(2):185-93. doi: 10.1038/eye.2011.288. Epub 2011 Dec 2.
citation: Cho P, Cheung SW. Retardation of myopia in Orthokeratology (ROMIO) study: a 2-year randomized clinical trial. Invest Ophthalmol Vis Sci. 2012 Oct 11;53(11):7077-85. doi: 10.1167/iovs.12-10565.
citation: Hiraoka T, Kakita T, Okamoto F, Takahashi H, Oshika T. Long-term effect of overnight orthokeratology on axial length elongation in childhood myopia: a 5-year follow-up study. Invest Ophthalmol Vis Sci. 2012 Jun 22;53(7):3913-9. doi: 10.1167/iovs.11-8453.
citation: Cheung SW, Boost MV, Cho P. Pre-treatment observation of axial elongation for evidence-based selection of children in Hong Kong for myopia control. Cont Lens Anterior Eye. 2019 Aug;42(4):392-398. doi: 10.1016/j.clae.2018.10.006. Epub 2018 Oct 24.