A 2-year Longitudinal Study on the Structural and Optical Effects of Orthokeratology Treatment on Eye

July 29, 2020 updated by: Pauline Cho, The Hong Kong Polytechnic University
This is a two-year longitudinal study investigating the optical and structural effects of increased compression factor of orthokeratology lens on eyes and the corresponding effect on change in choroidal thickness and therefore myopic control.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Actual)

99

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • China
      • Hong Kong, China
        • School of Optometry, The Hong Kong Polytechnic University

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

6 years to 10 years (CHILD)

Accepts Healthy Volunteers

Yes

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • 6 to 10 years old
  • Myopia: between 0.50 D and 4.00 D in both eyes
  • Astigmatism: <1.50 D; ≤ 1.25 D for with-the-rule astigmatism (axes 180 ± 30); ≤ 0.50 D for astigmatism of other axes in both eyes
  • Anisometropia: ≤ 1.50 D
  • Symmetrical corneal topography with corneal toricity <2.00 D in both eyes
  • Agree for randomization

Exclusion Criteria:

  • Contraindications for orthokeratology wear (e.g. limbus-to-limbus corneal cylinder and dislocated corneal apex)
  • Any type of strabismus or amblyopia
  • Myopic treatment (e.g. refractive surgery and progressive lens wear for myopic control) before and during the study period
  • Rigid contact lenses (including orthokeratology lenses) experience
  • Systemic condition which might affect refractive development (for example, Down syndrome, Marfan's syndrome)
  • Ocular conditions which might affect the refractive error (for example, cataract, ptosis)
  • Poor compliance for lens wear or follow-up

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: TREATMENT
  • Allocation: RANDOMIZED
  • Interventional Model: PARALLEL
  • Masking: SINGLE

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
NO_INTERVENTION: Single-vision glasses
Subjects wearing single-vision glasses CR-39 of refractive index 1.56.
SHAM_COMPARATOR: Orthokeratology with normal compression factor
Subjects wearing orthokeratology lenses of normal compression factor about 0.50-0.75D.
Device: Orthokeratology
Other Names:
  • ortho-k
ACTIVE_COMPARATOR: Orthokeratology with increased compression factor
Subjects wearing orthokeratology lenses of increased compression factor about 1.50-1.75D.
Device: Orthokeratology
Other Names:
  • ortho-k

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Axial length
Time Frame: every 6 monthly in 2 years
axial progression of the eyeball
every 6 monthly in 2 years

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Ocular aberration measured by Complete Ophthalmic Analysis System (COAS) aberrometer
Time Frame: every 6 monthly in 2 years
ocular aberration measured by Complete Ophthalmic Analysis System (COAS) aberrometer
every 6 monthly in 2 years
Corneal biomechanics (corneal response using ocular response)
Time Frame: every 6 monthly in 2 years
corneal response using ocular response
every 6 monthly in 2 years
Accommodation lag measured by Complete Ophthalmic Analysis System (COAS) aberrometer
Time Frame: every 6 monthly in 2 years
accommodation lag measured by Complete Ophthalmic Analysis System (COAS) aberrometer using different accommodation targets
every 6 monthly in 2 years
Choroidal thickness captured by Optical Coherent Tomographer (OCT)
Time Frame: every 6 monthly in 2 years
choroidal thickness captured by Optical Coherent Tomographer (OCT) and measured using a customized software
every 6 monthly in 2 years

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

The Hong Kong Polytechnic University

Collaborators

Aston University
Queensland University of Technology
Menicon Co., Ltd.

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (ACTUAL)

June 18, 2016

Primary Completion (ACTUAL)

August 3, 2019

Study Completion (ACTUAL)

August 3, 2019

Study Registration Dates

First Submitted

December 28, 2015

First Submitted That Met QC Criteria

December 30, 2015

First Posted (ESTIMATE)

December 31, 2015

Study Record Updates

Last Update Posted (ACTUAL)

July 30, 2020

Last Update Submitted That Met QC Criteria

July 29, 2020

Last Verified

February 1, 2020

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • HSEARS20150909002

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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