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Discontinuation of Orthokeratology on Eyeball Elongation in Myopic Children (DOEE1)

This study is currently recruiting participants.
Verified June 2011 by The Hong Kong Polytechnic University
Sponsor:
Collaborator:
Menicon Co., Ltd.
Information provided by:
The Hong Kong Polytechnic University
ClinicalTrials.gov Identifier:
NCT01236742
First received: November 8, 2010
Last updated: June 23, 2011
Last verified: June 2011
History of Changes
  Purpose

The primary aim of this study is to compare eyeball elongation in existing ortho-k subjects who stop the treatment with subjects who continue ortho-k lens wear and control subjects wearing single-vision glasses.


Condition Intervention
Myopia
 Procedure: Switching of orthokeratology and single-vision glasses

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Parallel Assignment
Masking: Single Blind (Outcomes Assessor)
Primary Purpose: Treatment
Official Title: Discontinuation of Orthokeratology on Eyeball Elongation (DOEE) Study. (1) Discontinuation of Lens Wear in Existing Ortho-k Children

Resource links provided by NLM:

U.S. FDA Resources

Further study details as provided by The Hong Kong Polytechnic University:

Primary Outcome Measures:
  • Axial length [ Time Frame: 14 months ] [ Designated as safety issue: No ]
    To determine the change in axial length in the study and control groups


Secondary Outcome Measures:
  • Incidence of adverse effects [ Time Frame: 14 months ] [ Designated as safety issue: Yes ]
    To determine the incidence of adverse effects on the cornea, the palpebral, bulbar and tarsal conjunctiva in the study and the control groups


Estimated Enrollment: 120
Study Start Date: July 2010
Estimated Study Completion Date: March 2013
Estimated Primary Completion Date: October 2012 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Discontinuation of ortho-k lenses
Children who are currently wearing ortho-k lenses at night for correction of refractive errors will be switched to wear single-vision glasses for the first 7 months and then switched back to ortho-k lenses for the next 7 months
 Procedure: Switching of orthokeratology and single-vision glasses
Daily use of spectacles to correct the refractive errors for a period of 7 months followed by ortho-k lenses for another 7 months
No Intervention: Continuation of ortho-k lenses
Children who are currently wearing ortho-k lenses at night for the correction of refractive errors will continue with the current treatment and serve as the first control group
No Intervention: Continuation of single-vision spectacles
Children who are currently wearing single-vision spectacles in the daytime for correcting their refractive errors will continue with the current treatment and serve as the second control group

Detailed Description:

Children wearing ortho-k have been shown to have slower rate of myopic progression than those wearing single-vision spectacles (Cho et al. 2005) or soft lenses (Walline et al. 2009). Both studies showed that the effect of myopic control was most significant during the first six months of the treatment. It is unknown whether the myopic control effect would dissipate upon the discontinuation of the treatment or whether the myopic control effect only happened in the first six month of lens wear and was maintained thereafter. The current study aims at evaluating the effect of discontinuation of ortho-k treatment on myopic control in children who are currently on the treatment. This knowledge is necessary and important as patients/parents have concerns about the permanent dependency on ortho-k once they enrolled in the treatment.

Children who have been on the treatment for two years and have recently completed the myopic control studies at The Hong Kong Polytechnic University, i.e. the ROMIO, TO-SEE and HM-PRO studies, will be invited to participate in this 14-month study. Ortho-k subjects will be randomly assigned to study group or the ortho-k control group. The study group subjects will be required to stop lens wear for 7 months at the completion of the previous study (Phase I) and resume lens wear for next 7 months (Phase II). The ortho-k control group subjects will be required to continue the current treatment for another 14 months. Control subjects in the existing myopic control studies will be required to continue using the same treatment, i.e. single-vision glasses, for another 14 months. Rate of myopic progression among the 3 groups and at the two study phases will be determined and compared.

  Eligibility

Ages Eligible for Study:   8 Years to 14 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Age 8-14 years old (inclusive)
  • Subjects who have completed the ROMIO, TO-SEE or HM-PRO studies at The Hong Kong Polytechnic University
  • Willingness to be randomized into groups (for ortho-k subjects)
  • Availability for follow-up for at least 14 months

Exclusion Criteria:

  • Non-compliance to the follow up schedule
  • Non-compliance to the assigned optical correction (i.e. single-vision glasses or ortho-k lenses)
  • Contraindication for contact lens wear and ortho-k (e.g. limbus to limbus corneal cylinder and dislocated corneal apex)
  • Systemic or ocular) conditions which may affect contact lens wear (e.g. allergy and medication)
  • Systemic or ocular conditions which may affect refractive development (e.g. Down syndrome, ptosis)
  Contacts and Locations
Please refer to this study by its ClinicalTrials.gov identifier: NCT01236742

Contacts
Contact: Pauline Cho, PhD (852) 2766 6100 sopaulin@inet.polyu.edu.hk
Contact: Sin Wan Cheung, MPhil (852) 2766 4462 sopeggy@inet.polyu.edu.hk

Locations
China
School of Optometry, The Hong Kong Polytechnic University Recruiting
Hong Kong SAR, China
Contact: Pauline Cho, PhD     (852) 2766 6100     sopaulin@inet.polyu.edu.hk    
Contact: Sin Wan Cheung, MPhil     (852) 2766 4462     sopeggy@inet.polyu.edu.hk    
Sponsors and Collaborators
The Hong Kong Polytechnic University
Menicon Co., Ltd.
Investigators
Principal Investigator: Pauline Cho, PhD The Hong Kong Polytechnic University
  More Information

Publications:

Responsible Party: Dr Pauline Cho, School of Optometry, The Hong Kong Polytechnic University
ClinicalTrials.gov Identifier: NCT01236742     History of Changes
Other Study ID Numbers: H-ZG50-1
Study First Received: November 8, 2010
Last Updated: June 23, 2011
Health Authority: Hong Kong: Ethics Committee

Keywords provided by The Hong Kong Polytechnic University:
children
corneal reshaping
myopia
myopia progression
orthokeratology

Additional relevant MeSH terms:
Myopia
Refractive Errors
Eye Diseases

ClinicalTrials.gov processed this record on May 16, 2013