Myopic Control for High Myopes Using Orthokeratology

Myopia Clinical Trial

— HM-PRO  

Official title:

High Myopia - Partial Reduction Orthokeratology Study

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00977236
• Other study ID #: 4-RP3M
• Status: Completed
• Phase: N/A
• First received: September 14, 2009
• Last updated: July 11, 2013
• Start date: July 2008
• Est. completion date: December 2012

Study information

• Verified date: July 2013
• Source: The Hong Kong Polytechnic University
• Contact: n/a
• Is FDA regulated: No
• Health authority: Hong Kong: Ethics Committee
• Study type: Interventional

Clinical Trial Summary

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.

Description:

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.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 52
• Est. completion date: December 2012
• Est. primary completion date: December 2011
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Both
• Age group: 8 Years to 11 Years

Eligibility

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)

Study Design

Allocation: Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Parallel Assignment, Masking: Single Blind (Investigator), Primary Purpose: Treatment

Related Conditions & MeSH terms

• Myopia

Intervention

Device:
• Orthokeratology lenses
Nightly use of orthokeratology to correct the refractive error and over-specs for a period of two years
• Single-vision spectacle lenses
Daily use of spectacles to correct the refractive error for a period of two years

Locations

Country	Name	City	State
China	School of Optometry, The Hong Kong Polytechnic University	Hong Kong SAR

Sponsors (2)

Lead Sponsor	Collaborator
The Hong Kong Polytechnic University	Procornea Nederland B.V.

Country where clinical trial is conducted

China, 

References & Publications (4)

Charm J, Cho P. High myopia-partial reduction ortho-k: a 2-year randomized study. Optom Vis Sci. 2013 Jun;90(6):530-9. doi: 10.1097/OPX.0b013e318293657d. — View Citation

Charm J, Cho P. High myopia-partial reduction orthokeratology (HM-PRO): study design. Cont Lens Anterior Eye. 2013 Aug;36(4):164-70. doi: 10.1016/j.clae.2013.02.012. Epub 2013 Mar 18. — View Citation

Cho P, Cheung SW, Edwards M. The longitudinal orthokeratology research in children (LORIC) in Hong Kong: a pilot study on refractive changes and myopic control. Curr Eye Res. 2005 Jan;30(1):71-80. — View Citation

Walline JJ, Jones LA, Sinnott LT. Corneal reshaping and myopia progression. Br J Ophthalmol. 2009 Sep;93(9):1181-5. doi: 10.1136/bjo.2008.151365. Epub 2009 May 4. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Determine the change in cycloplegic axial length in the study and control groups		2 years	No
Secondary	Determine the incidence of adverse effects in cornea, the palpebral, bulbar and tarsal conjunctiva in the study and the control groups		2 years	Yes
Secondary	Rate of regression during the daytime		2 years	No

External Links

•   High myopia-partial reduction ortho-k: a 2-year randomized study
•   High myopia-partial reduction orthokeratology (HM-PRO): Study design.