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Effectiveness of Orthokeratology in Myopia Control

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ClinicalTrials.gov Identifier: NCT03465748
Recruitment Status : Recruiting
First Posted : March 14, 2018
Last Update Posted : March 16, 2018
Sponsor:
Collaborator:
Wesley Research Institute
Information provided by (Responsible Party):
Jennifer Harthan, Illinois College of Optometry

Brief Summary:
The high prevalence of myopia - especially in Asian countries - is well documented, as are the sight-threatening complications of high or degenerative myopia. Retinal detachment, glaucoma, vitreal degeneration and focal retinal changes may occur secondary to the progressive axial elongation of the eye with age. Specialty rigid lenses have long been shown to lessen this progression in the pediatric population; orthokeratology (ortho-k) lenses are worn at night and change the corneal topography to correct low to moderate amounts of myopia. Most of the studies on orthokeratology were conducted on Asian children. To the best of the investigators knowledge, no study has been done on African American (AA) children. The investigators' project seeks to investigate the efficacy of ortho-k in slowing axial elongation and myopic progression in AA children compared to that in other races.

Condition or disease Intervention/treatment Phase
Myopia Device: OrthoK Not Applicable

Detailed Description:

Orthokeratology (ortho-k), when used for partial or full correction of myopia, has been shown to slow myopic progression in children by 36-56% as compared to their spectacle or contact-lens wearing peers.1 This effect is achieved by limiting the axial elongation of the eye,1, 2,3, 4 which is of particular concern in high myopes (>6.00D) and children, where myopic progression has been shown to proceed at a faster rate than average.1 As early intervention is considered beneficial if not essential, Ortho-k as a treatment modality for diminishing myopic progression has, to our knowledge, been studied mostly in Asian children.

The safety and efficacy of ortho-k as a means of decreasing myopic progression was well established by the Children's Overnight Orthokeratology Investigation (COOKI), who evaluated refractive error, visual changes and ocular health over a period of 6 months in myopic children. 7 The Longitudinal Orthokeratology Research in Children (LORIC) study looked at axial elongation in children as old as 12 years, and found that ortho-k decreased axial elongation by approximately 50% compared to be-spectacled controls. 2 They also noted, however, high variability amongst the children that limits the clinician's ability to predict the outcome of the intervention.2 The Corneal Reshaping and Yearly Observation of Myopia (CRAYON) study confirmed that patients fit with ortho-k lenses showed less change in axial length and vitreous chamber depth when compared to subjects wearing soft contact lenses. 3 Other more recent studies by Santodomingo-Rubido et al, 7 Kakita et al4 and Charm et al1 confirm this decrease in axial elongation using IOL Master measurements.

The most commonly accepted theory on how orthokeratology decreases axial elongation relies on the peripheral defocus created on the retina by the corneal changes made by the rigid lens. 9 Hoogerheide et al showed that those at greatest risk for myopic progression were those whose peripheral refraction was hypermetropic10 - that is, they had a hyperopic peripheral 'defocus'. A number of studies have since suggested that treatment approaches to myopia correction should address this peripheral refraction as a means of slowing further axial elongation.9 When looking at subjects treated with ortho k, we see that the lenses do in fact introduce a peripheral myopic defocus while leaving the central refraction more or less emmetropic. 9 With this study, the investigators hope to expand potential application of orthokeratology to a novel population, AA children.


Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 60 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Prevention
Official Title: Effectiveness of Orthokeratology in Myopia Control
Actual Study Start Date : May 1, 2017
Estimated Primary Completion Date : May 2019
Estimated Study Completion Date : May 2019

Resource links provided by the National Library of Medicine


Arm Intervention/treatment
Experimental: Experimental-OrthoK
The study will be a randomized control study using a single-masked design to investigate axial elongation and myopic progression in children wearing ortho-k lenses (study group) versus single-vision spectacles or soft contact lenses (control group) for a period of 24 months. A minimum of 40 and a maximum of 60 subjects will be recruited from patients at Illinois Eye Institute. Once eligibility has been determined by an unmasked observer, patients will be randomly assigned to either the orthokeratology group or the single-vision contact lens /spectacle group
Device: OrthoK
orthok (orthokeratology) is the science of changing the curvature or shape of the cornea to change how light is focused on the retina at the back of one's eye. Specially designed molding retainer contact lenses are placed on the eye at night and are removed upon awakening.

No Intervention: Control
The study will be a randomized control study using a single-masked design to investigate axial elongation and myopic progression in children wearing ortho-k lenses (study group) versus single-vision spectacles (control group) for a period of 24 months. A minimum of 40 and a maximum of 60 subjects will be recruited from patients at Illinois Eye Institute. Once eligibility has been determined by an unmasked observer, patients will be randomly assigned to either the orthokeratology group or the single-vision contact lens /spectacle group



Primary Outcome Measures :
  1. VA [ Time Frame: 2 years ]
    Visual Acuity

  2. Axial Length [ Time Frame: 2 years ]
    Axial Length

  3. Myopia Progression [ Time Frame: 2 years ]
    Autrorefraction



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Ages Eligible for Study:   6 Years to 13 Years   (Child)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • myopia progression more than -1.00D in one year
  • myopic prescription between -1.00D and -6.00D in at least one eye with refractive astigmatism <1.50D
  • Best corrected VA 20/25 or better
  • subjects willing to present to clinic for all necessary follow up care
  • willing to be randomized to either group

Exclusion Criteria:

  • non-compliance with treatment protocol
  • contraindications for orthok as per company guidelines
  • history of refractive surgery
  • current gas permeable contact lens wearers

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03465748


Contacts
Contact: Jennifer Harthan, OD 312-949-7137 JHarthan@ico.edu
Contact: Elyse Nylin 312-949-7298 ENylin@ico.edu

Locations
United States, Illinois
Illinois Eye Institute Recruiting
Chicago, Illinois, United States, 60616
Contact: Elyse Nylin    312-949-7298    ENylin@ico.edu   
Sponsors and Collaborators
Illinois College of Optometry
Wesley Research Institute
Investigators
Study Chair: Yi Pang, OD Illinois College of Optometry

Publications:
Responsible Party: Jennifer Harthan, Chief, Cornea Center for Clinical Excellence, Illinois College of Optometry
ClinicalTrials.gov Identifier: NCT03465748     History of Changes
Other Study ID Numbers: 15021
First Posted: March 14, 2018    Key Record Dates
Last Update Posted: March 16, 2018
Last Verified: March 2018
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No

Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: Yes
Device Product Not Approved or Cleared by U.S. FDA: No
Pediatric Postmarket Surveillance of a Device Product: No
Product Manufactured in and Exported from the U.S.: No

Additional relevant MeSH terms:
Myopia
Refractive Errors
Eye Diseases