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Orthokeratology for High Myopia (OHM) Study

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ClinicalTrials.gov Identifier: NCT03881358
Recruitment Status : Recruiting
First Posted : March 19, 2019
Last Update Posted : March 19, 2019
Sponsor:
Collaborators:
Queensland University of Technology
Aston University
Information provided by (Responsible Party):
Pauline Cho, The Hong Kong Polytechnic University

Tracking Information
First Submitted Date  ICMJE February 21, 2019
First Posted Date  ICMJE March 19, 2019
Last Update Posted Date March 19, 2019
Actual Study Start Date  ICMJE August 4, 2018
Estimated Primary Completion Date August 2021   (Final data collection date for primary outcome measure)
Current Primary Outcome Measures  ICMJE
 (submitted: March 18, 2019)
Change in axial length elongation over 24 months. [ Time Frame: 2 years ]
To determine the change in axial length measured at baseline and two years after lens wear using IOLMaster
Original Primary Outcome Measures  ICMJE Same as current
Change History No Changes Posted
Current Secondary Outcome Measures  ICMJE
 (submitted: March 18, 2019)
  • First fit success rate of a newly designed ortho-k lens for high myopic children [ Time Frame: 1 month ]
    The success rate in using the first pair of lenses to achieve target refractive correction will be determined
  • Quality of life (questionnaire) [ Time Frame: 3 months ]
    Quality of life will be determined by questionnaires (using revised PREP1 in traditional Chinese version) before and after ortho-k in the two groups of subjects
  • Ocular aberration [ Time Frame: 2 years ]
    Ocular aberration will be measured by Complete Ophthalmic Analysis System (COAS) aberrometer
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 Orthokeratology for High Myopia (OHM) Study
Official Title  ICMJE Orthokeratology for High Myopia (OHM) Study
Brief Summary This project aims to investigate/examine high myopic subjects on full correction ortho-k (using Topaz ortho-k lenses for high myopia) compared to subjects undergoing partial reduction ortho-k and their relationship with myopia and myopic progression.
Detailed Description

For many years, commercially-available ortho-k lenses aim to reduce low - moderate myopia. Attempts to use these lenses for reduction of high myopia have been shown to give rise to complications such as corneal staining and lens decentration. Thus, practitioners may choose a more conservative way for high myopic children, that is, offering partial reduction ortho-k. Partial reduction ortho-k is target for 4.00-5.00D reduction and the residual refractive errors will be corrected with single vision spectacles to allow good visual acuity in the daytime. Partial reduction ortho-k has been shown to slow axial elongation in high myopic children, however, the main disadvantage is that the children have to wear spectacles in the daytime to correct residual refraction.

Euclid has recently designed a new lens, Euclid's Topaz, for high myopic children. It is currently commercially available to correct myopia for up to 10 D. However, evidence of its effectiveness for visual correction and slowing AL growth is lacking. While numerous studies have shown that orthokeratology is an effective clinical treatment to slow axial eye growth in children, the exact mechanism underlying this reduction in myopia progression associated with orthokeratology remains unclear.

Study Type  ICMJE Interventional
Study Phase  ICMJE Not Applicable
Study Design  ICMJE Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single (Outcomes Assessor)
Primary Purpose: Treatment
Condition  ICMJE
  • Myopia
  • High Myopia
Intervention  ICMJE
  • Device: ortho-k lenses and thinner spectacles
    Conventinally designed (Emerald) ortho-k lenses (target for -4.00D) and thinner specs during day time
  • Device: newly designed ortho-k lenses
    Newly designed (Topaz) ortho-k lenses for high myopia (target for full correction)
Study Arms  ICMJE
  • Active Comparator: ortho-k lenses and thinner spectacles
    participants using conventionally designed ortho-k lenses (target for 4.00D) and thinner spectacles during day time
    Intervention: Device: ortho-k lenses and thinner spectacles
  • Experimental: newly designed ortho-k lenses
    participants using newly designed ortho-k lenses for high myopia (target for full correction)
    Intervention: Device: newly designed ortho-k lenses
Publications *

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
 
Recruitment Information
Recruitment Status  ICMJE Recruiting
Estimated Enrollment  ICMJE
 (submitted: March 18, 2019)
66
Original Estimated Enrollment  ICMJE Same as current
Estimated Study Completion Date  ICMJE October 2021
Estimated Primary Completion Date August 2021   (Final data collection date for primary outcome measure)
Eligibility Criteria  ICMJE

Inclusion Criteria:

  • Myopia: at least 5.00D in one eye or in both eyes
  • Astigmatism: ≤1.50D; with-the-rule astigmatism (axes 180 ± 30) ≤1.25D; astigmatism of other axes ≤0.50D in both eyes
  • Anisometropia: not be more than 1.00D in the former and not more than 2.00D in the latter.
  • Best-corrected Monocular Snellen visual acuity 6/7.5 or better

Exclusion Criteria:

  • Strabismus at distance or near
  • Previous experience in contact lens wear or myopia control treatment (e.g. refractive therapy or progressive spectacles)
  • Contraindication for contact lens wear and orthokeratology (e.g. limbus to limbus corneal cylinder and dislocated corneal apex)
  • Previous history of ocular surgery, trauma, or chronic ocular disease
  • Concurrent use of medications that may affect tear quality or contact lens wear
  • Systemic or ocular conditions that may affect tear quality or contact lens wear (e.g allergy and concurrent medication) or that may affect refractive development (e.g Down syndrome, ptosis)
  • Poor compliance to tests (e.g poor fixation in noncontact tonometry or intolerance of lens wear)
  • Not willing to comply with the allocated treatment, use and care of lenses and follow-up schedule
Sex/Gender  ICMJE
Sexes Eligible for Study: All
Ages  ICMJE 7 Years to 13 Years   (Child)
Accepts Healthy Volunteers  ICMJE Yes
Contacts  ICMJE
Contact: Pauline Cho, PhD (+852) 2766 6100 pauline.cho@polyu.edu.hk
Contact: Yajing Yang, BSc (+852) 6486 2435 grace.yj.yang@connect.polyu.hk
Listed Location Countries  ICMJE Hong Kong
Removed Location Countries  
 
Administrative Information
NCT Number  ICMJE NCT03881358
Other Study ID Numbers  ICMJE HSEARS20180322002
Has Data Monitoring Committee Yes
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: Undecided
Responsible Party Pauline Cho, The Hong Kong Polytechnic University
Study Sponsor  ICMJE The Hong Kong Polytechnic University
Collaborators  ICMJE
  • Queensland University of Technology
  • Aston University
Investigators  ICMJE
Principal Investigator: Pauline Cho, PhD The Hong Kong Polytechnic University
PRS Account The Hong Kong Polytechnic University
Verification Date March 2019

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