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Myopic Control for High Myopes Using Orthokeratology (HM-PRO)

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.
ClinicalTrials.gov Identifier: NCT00977236
Recruitment Status : Completed
First Posted : September 15, 2009
Last Update Posted : July 12, 2013
Information provided by (Responsible Party):

September 14, 2009
September 15, 2009
July 12, 2013
July 2008
December 2011   (Final data collection date for primary outcome measure)
Determine the change in cycloplegic axial length in the study and control groups [ Time Frame: 2 years ]
Same as current
Complete list of historical versions of study NCT00977236 on ClinicalTrials.gov Archive Site
  • Determine the incidence of adverse effects in cornea, the palpebral, bulbar and tarsal conjunctiva in the study and the control groups [ Time Frame: 2 years ]
  • Rate of regression during the daytime [ Time Frame: 2 years ]
Same as current
Not Provided
Not Provided
Myopic Control for High Myopes Using Orthokeratology
High Myopia - Partial Reduction Orthokeratology Study
The purpose of this study is to evaluate and compare the eyeball elongation in high myopic children using partial correction orthokeratology and single-vision spectacles.

Orthokeratology (ortho-k) has been shown to have strong potential for retardation of myopic progression in low myopes. To date, clinical experience has shown the technique to be less effective in achieving full myopic reduction in high myopes. Would myopic control be possible for high myopes undergoing partial correction ortho-k treatment?

A randomized, longitudinal study is designed to investigate the efficacy of partial correction ortho-k in retardation of myopic progression in high myopic children. Eye growth in terms of axial length elongation in children wearing ortho-k and over-spectacles (to correct residual refractive errors) (study group) and those wearing single-vision spectacles (control group) will be evaluated and compared.

Not Provided
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single (Investigator)
Primary Purpose: Treatment
  • Device: Orthokeratology lenses
    Nightly use of orthokeratology to correct the refractive error and over-specs for a period of two years
    Other Name: Corneal reshaping therapy
  • Device: Single-vision spectacle lenses
    Daily use of spectacles to correct the refractive error for a period of two years
    Other Names:
    • Glasses
    • Spectacles
  • Experimental: Orthokeratology lenses
    Children wearing orthokeratology at night for partial correction and spectacles at daytime for residual refractive error will be study group
    Intervention: Device: Orthokeratology lenses
  • Single-vision spectacle lenses
    Children wearing single-vision spectacles in the daytime for correcting the refractive error will serve as control group
    Intervention: Device: Single-vision spectacle lenses

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
December 2012
December 2011   (Final data collection date for primary outcome measure)

Inclusion Criteria:

  • Myopia (refractive sphere): > 5.75D
  • Astigmatism: < ½ of myopia; with-the-rule astigmatism (axes 180 +/- 30) ≤1.25D; astigmatism of other axes ≤ 0.50D
  • Spherical equivalent (SE): > 5.75D
  • Anisometropia: ≤ 1.50D in both refractive sphere, refractive cylinder and SE
  • Best corrected monocular visual acuity: equal to or better than 0.10 in logMAR scale in both eyes
  • Willingness for randomization
  • Availability for follow-up for at least 2 years

Exclusion Criteria:

  • Strabismus at distance or near
  • Contraindication for contact lens wear and orthokeratology (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)
Sexes Eligible for Study: All
8 Years to 11 Years   (Child)
Contact information is only displayed when the study is recruiting subjects
Not Provided
Not Provided
Pauline Cho, The Hong Kong Polytechnic University
The Hong Kong Polytechnic University
Procornea Nederland B.V.
Principal Investigator: Pauline Cho The Hong Kong Polytechnic University
The Hong Kong Polytechnic University
July 2013

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