NCT00978692

Brief Summary

The aims of this study are to investigate the effects of ortho-k for astigmatic and myopic reduction and myopic control in children, and the long term effects on corneal curvatures and biomechanics.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
80

participants targeted

Target at P50-P75 for not_applicable

Timeline
Completed

Started May 2008

Longer than P75 for not_applicable

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

May 1, 2008

Completed
1.4 years until next milestone

First Submitted

Initial submission to the registry

September 16, 2009

Completed
1 day until next milestone

First Posted

Study publicly available on registry

September 17, 2009

Completed
2.8 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

July 1, 2012

Completed
5 months until next milestone

Study Completion

Last participant's last visit for all outcomes

December 1, 2012

Completed
Last Updated

February 22, 2016

Status Verified

February 1, 2016

Enrollment Period

4.2 years

First QC Date

September 16, 2009

Last Update Submit

February 18, 2016

Conditions

MyopiaAstigmatism

Keywords

MyopiaAstigmatismOrthokeratologyCorneal thicknessCorneal curvaturesCorneal biomechanics

Outcome Measures

Primary Outcomes (1)

  • To determine the eyeball elongation in children wearing ortho-k lenses

    Before lens wear, 6, 12,18, 24 months after lens wear

Secondary Outcomes (2)

  • To determine the posterior corneal curvatures, topographic corneal thickness, corneal volume, corneal hysteresis and corneal resistance factor in a group of children and compare these parameters with the ortho-k children

    Before lens wear, 6, 12,18, 24 months after lens wear

  • To investigative the efficacy of toric orthokeratology for correcting astigmatism and myopia

    Before lens wear, 6, 12,18, 24 months after lens wear

Study Arms (2)

Toric orthokeratology lenses

EXPERIMENTAL

Children wearing toric ortho-k lenses at night for correcting astigmatism and myopia will be the study group

Device: Toric Orthokeratology lenses

Single-vision spectacles

OTHER

Children wearing single-vision spectacles in the daytime for correcting the refractive error will be serve as control group

Device: Single-vision spectacles

Interventions

Toric Orthokeratology lensesDEVICE

Children wearing toric orthokeratology at night for correcting astigmatism and myopia will be the study group

Also known as: corneal reshaping therapy
Toric orthokeratology lenses
Single-vision spectaclesDEVICE

Children wearing single-vision spectacles in the daytime for correcting the refractive errors will serve as the control group

Also known as: glasses
Single-vision spectacles

Eligibility Criteria

Age6 Years - 12 Years
Sexall
Healthy VolunteersYes
Age GroupsChild (0-17)

You may qualify if:

  • Myopia (refractive sphere): more than -0.50DS to -5.00DS
  • Astigmatism: with-the-rule astigmatism more than -1.25DC
  • Anisometropia: ≤ 1.50D in both refractive sphere
  • Best corrected monocular visual acuity: equal to or better than 0.10 in logMAR scale in both eyes
  • Availability for follow-up for at least 2 years

You may not qualify if:

  • Strabismus at distance or near
  • Contraindication for contact lens wear and orthokeratology (e.g. limbus to limbus corneal cylinder and dislocated corneal apex
  • Prior experience with the use of rigid lenses (including orthokeratology)
  • Prior experience with myopia control treatment (e.g. refractive therapy or progressive spectacles)
  • 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)

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

School of Optometry, The Hong KOng Polytechnic University

Hong Kong SAR, China

Location

Related Publications (3)

  • Chen C, Cheung SW, Cho P. Myopia control using toric orthokeratology (TO-SEE study). Invest Ophthalmol Vis Sci. 2013 Oct 3;54(10):6510-7. doi: 10.1167/iovs.13-12527.

    PMID: 24003088BACKGROUND

  • Chen CC, Cheung SW, Cho P. Toric orthokeratology for highly astigmatic children. Optom Vis Sci. 2012 Jun;89(6):849-55. doi: 10.1097/OPX.0b013e318257c20f.

    PMID: 22561203BACKGROUND

  • Chen C, Cho P. Toric orthokeratology for high myopic and astigmatic subjects for myopic control. Clin Exp Optom. 2012 Jan;95(1):103-8. doi: 10.1111/j.1444-0938.2011.00616.x. Epub 2011 Sep 5. No abstract available.

    PMID: 21895768BACKGROUND

MeSH Terms

Conditions

MyopiaAstigmatism

Interventions

Eyeglasses

Condition Hierarchy (Ancestors)

Refractive ErrorsEye Diseases

Intervention Hierarchy (Ancestors)

LensesOptical DevicesEquipment and Supplies

Study Officials

  • Pauline Cho, PhD

    The Hong Kong Polytechnic University

    PRINCIPAL INVESTIGATOR

Study Design

Study Type
interventional
Phase
not applicable
Allocation
NON RANDOMIZED
Masking
SINGLE
Who Masked
INVESTIGATOR
Purpose
TREATMENT
Intervention Model
PARALLEL
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Professor

Study Record Dates

First Submitted

September 16, 2009

First Posted

September 17, 2009

Study Start

May 1, 2008

Primary Completion

July 1, 2012

Study Completion

December 1, 2012

Last Updated

February 22, 2016

Record last verified: 2016-02

Locations

CN(1)