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Effectiveness of Myopia Control by Breath-O Correct Orthokeratology Lenses

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT03919396
Recruitment Status : Active, not recruiting
First Posted : April 18, 2019
Last Update Posted : August 27, 2021
SEED Co. Ltd.
Information provided by (Responsible Party):
The Hong Kong Polytechnic University

Tracking Information
First Submitted Date  ICMJE April 16, 2019
First Posted Date  ICMJE April 18, 2019
Last Update Posted Date August 27, 2021
Actual Study Start Date  ICMJE April 1, 2019
Actual Primary Completion Date October 31, 2019   (Final data collection date for primary outcome measure)
Current Primary Outcome Measures  ICMJE
 (submitted: April 28, 2019)
Subjective Refraction [ Time Frame: up to 24 months ]
Refractive Error ( in Diopter )
Original Primary Outcome Measures  ICMJE
 (submitted: April 16, 2019)
Refractive Errors [ Time Frame: up to 24 months ]
Refractive Errors
Change History
Current Secondary Outcome Measures  ICMJE
 (submitted: April 16, 2019)
Axial Length [ Time Frame: up to 24 months ]
Length of eye ball
Original Secondary Outcome Measures  ICMJE Same as current
Current Other Pre-specified Outcome Measures Not Provided
Original Other Pre-specified Outcome Measures Not Provided
Descriptive Information
Brief Title  ICMJE Effectiveness of Myopia Control by Breath-O Correct Orthokeratology Lenses
Official Title  ICMJE Effectiveness of Myopia Control by Breath-O Correct Orthokeratology Lenses in Different Myopia Progression Groups
Brief Summary This is a 24-month longitudinal randomized controlled trial aiming to evaluate the effectiveness of myopia control by Breath-O correct orthokeratology lenses in different myopia progression groups classified according to their initial electro-retinal responses.
Detailed Description

Myopia is the most common refractive error in the world. In Hong Kong, the number of children in myopia is on the rise and approximately 80% of children are myopic by the end of childhood. Orthokeratology is one of the most successful myopia control methods adopting the strategy of peripheral defocus, in which the natural emmetropization process is harnessed by the myopic defocus induced by the orthokeratology lenses.Currently, Breath-O correct lenses are new designed ready-made orthokeratology lenses which are made of new material with higher elasticity as compared traditional lens material.

A recent study has shown young children with an initial weakened central electrical signal from the inner retina had faster myopia progression as measured by multifocal electroretinogram(ERG). We will classify the slow and fast progression group based on the ERG results, so as to evaluate the clinical effectiveness of the newly designed lenses in controlling myopia in children with different rates of progression.

Study Type  ICMJE Interventional
Study Phase  ICMJE Not Applicable
Study Design  ICMJE Allocation: Randomized
Intervention Model: Parallel Assignment
Intervention Model Description:
Randomized clinical trial
Masking: None (Open Label)
Primary Purpose: Treatment
Condition  ICMJE
  • Myopia
  • Orthokeratology
Intervention  ICMJE Device: Breath-O orthokeratology lenses

Specially designed rigid gas permeable lenses which

  1. reshapes corneal profile for myopia control
  2. has higher elasticity compared to traditional lens material.
Study Arms  ICMJE
  • Experimental: OrthoK
    Group wearing Breath-O corrected orthokeratology lenses for 2 years
    Intervention: Device: Breath-O orthokeratology lenses
  • No Intervention: SV Lenses
    Group wearing spectacle with single vision lenses for 2 years
Publications * Not Provided

*   Includes publications given by the data provider as well as publications identified by Identifier (NCT Number) in Medline.
Recruitment Information
Recruitment Status  ICMJE Active, not recruiting
Estimated Enrollment  ICMJE
 (submitted: April 16, 2019)
Original Estimated Enrollment  ICMJE Same as current
Estimated Study Completion Date  ICMJE March 31, 2022
Actual Primary Completion Date October 31, 2019   (Final data collection date for primary outcome measure)
Eligibility Criteria  ICMJE

Inclusion Criteria:

  • Refractive error: Spherical: -1.00D to -4.00D; Cylindrical: half of Sph (against-the-rule Astig.: less than -0.75D)
  • Best corrected Visual acuity: monocular ETDRS 0.1 or better

Exclusion Criteria:

  • Ocular abnormality
  • Contra-indicated for overnight orthokeratology lens wear
  • History of refractive surgery
  • Systemic diseases
  • History of orthokeratology lenses wearing or other myopia control methods
Sex/Gender  ICMJE
Sexes Eligible for Study: All
Ages  ICMJE 8 Years to 12 Years   (Child)
Accepts Healthy Volunteers  ICMJE Yes
Contacts  ICMJE Contact information is only displayed when the study is recruiting subjects
Listed Location Countries  ICMJE Hong Kong
Removed Location Countries  
Administrative Information
NCT Number  ICMJE NCT03919396
Other Study ID Numbers  ICMJE HongKongPU_Optometry3
Has Data Monitoring Committee No
U.S. FDA-regulated Product
Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
IPD Sharing Statement  ICMJE
Plan to Share IPD: No
Current Responsible Party The Hong Kong Polytechnic University
Original Responsible Party Same as current
Current Study Sponsor  ICMJE The Hong Kong Polytechnic University
Original Study Sponsor  ICMJE Same as current
Collaborators  ICMJE SEED Co. Ltd.
Investigators  ICMJE
Principal Investigator: Henry HL Chan, PhD The Hong Kong Polytechnic University
PRS Account The Hong Kong Polytechnic University
Verification Date August 2021

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP