Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12608000007336
Ethics application status
Approved
Date submitted
7/01/2008
Date registered
9/01/2008
Date last updated
23/01/2014
Type of registration
Prospectively registered

Titles & IDs
Public title
The future of corneal refractive reshaping: can we control myopia or is the risk of corneal compromise too great?
Scientific title
A prospective, randomised, controlled, cross-over study to evaluate the effects of orthokeratology versus conventional rigid gas permeable contact lens wear on the progression of myopia in children and adolescents.
Secondary ID [1] 283968 0
Nil known
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Progressing mild childhood myopia 2672 0
Condition category
Condition code
Eye 2794 2794 0 0
Diseases / disorders of the eye

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Subjects with progressing myopia will wear an orthokeratology lens (BE design; RD1800 material) in one eye on an overnight basis, and a conventional rigid gas-permeable (RGP) contact lens (J-Contour design, RD1800 material) in the other eye for either daily or extended wear, for a 6-month period. After 6 months, the eye/lens combinations will be reversed and the lenses worn for a further 6 months.
Intervention code [1] 2414 0
Treatment: Devices
Comparator / control treatment
A matched control group of spectacle-wearing subjects will be enrolled and followed for 12 months. The conventional RGP lens-wearing eye will also act as a contralateral control in the lens-wearing group.
Control group
Active

Outcomes
Primary outcome [1] 3678 0
The primary outcome variable will be axial length change as measured using the IOLMaster ocular biometer.
Timepoint [1] 3678 0
Axial length will be measured at baseline, and 3, 6, 9 and 12 months after commencement of lens wear.
Secondary outcome [1] 6211 0
The relative rate of corneal epithelial cell exfoliation during gentle eye wash with sterile saline, and the amount of bacterial binding to harvested epithelial cells will be determined using a previously published method (Ren et al, 1999).
Timepoint [1] 6211 0
Cell exfoliation rate and bacterial binding will be determined at baseline, and 3, 6, 9 and 12 months after commencement of lens wear.
Secondary outcome [2] 6212 0
Peripheral refractive status will be determined at 10 degree intervals out to 30 degrees along the horizontal meridian using a Shin-Nippon NVision K5001 autorefractor.
Timepoint [2] 6212 0
Peripheral refraction will be measured at baseline, and 3, 6, 9 and 12 months after commencement of lens wear.

Eligibility
Key inclusion criteria
Participants will be required to have myopic refractive error between -1.00 and -4.00D at the time of study enrolment, evidence of progression of myopia over the previous 12 months, <0.75D refractive difference between the two eyes, <1.50D with-the-rule corneal astigmatism, and no against-the-rule astigmatism. Subjects must be of East Asian ethnicity, have good general and ocular health, and no history of rigid contact lens wear. Normal corneal topography, normal binocular function, and vision correctable to 6/9 (20/30) or better are also required for study enrolment.
Minimum age
8 Years
Maximum age
16 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Potential subjects will not be enrolled if they show any contraindications for rigid contact lens wear, abnormal binocular function, anisometropia > 0.75D, ocular pathology or active ocular surface disease that would preclude contact lens wear.

Study design
Purpose of the study
Prevention
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Randomly generated allocations will be held in sealed envelopes by a third party not directly involved in the trial. Allocation to lens-wearing versus spectacle-wearing (control) groups, and the lens/eye combination to be worn for the first 6 months for the lens-wearing group, will be determined by opening the next envelope in the appropriate sequence.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
The sequence will be generated by computer generated block randomisation methods, designed to stratify participants by severity of myopia and age, so that treatment and control groups are balanced.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?



Intervention assignment
Other
Other design features
The treatment group (contact lens-wearing group) will be assigned as a cross-over group. The control (spectacle-wearing) group will be assigned as a parallel group.
Phase
Not Applicable
Type of endpoint/s
Safety/efficacy
Statistical methods / analysis

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
14/01/2008
Actual
23/01/2008
Date of last participant enrolment
Anticipated
Actual
24/04/2009
Date of last data collection
Anticipated
Actual
Sample size
Target
75
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)

Funding & Sponsors
Funding source category [1] 2926 0
Government body
Name [1] 2926 0
Australian Research Council (ARC) Linkage Project Grant Scheme
Country [1] 2926 0
Australia
Funding source category [2] 2927 0
Commercial sector/Industry
Name [2] 2927 0
Boston Products Group of Bausch & Lomb
Country [2] 2927 0
United States of America
Funding source category [3] 2928 0
Commercial sector/Industry
Name [3] 2928 0
BE Enterprises Pty Ltd
Country [3] 2928 0
Australia
Funding source category [4] 2929 0
Commercial sector/Industry
Name [4] 2929 0
Capricornia Contact Lens Pty Ltd
Country [4] 2929 0
Australia
Primary sponsor type
Individual
Name
Prof Helen Swarbrick
Address
School of Optometry and Vision Science, University of New South Wales, Sydney NSW 2052
Country
Australia
Secondary sponsor category [1] 2643 0
None
Name [1] 2643 0
Address [1] 2643 0
Country [1] 2643 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 4871 0
University of New South Wales Human Research Ethics Committee
Ethics committee address [1] 4871 0
University of New South Wales, Sydney NSW 2052
Ethics committee country [1] 4871 0
Australia
Date submitted for ethics approval [1] 4871 0
Approval date [1] 4871 0
16/08/2007
Ethics approval number [1] 4871 0
HREC 07032

Summary
Brief summary
This study aims to determine whether the use of overnight orthokeratology contact lenses slows the progression of eye growth in myopic children and adolescents compared to conventional rigid contact lens wear and spectacle use. At the same time the relative risk for corneal infection (microbial keratitis) with overnight orthokeratology will be evaluated indirectly, using a well-established technique that analyses corneal cell shedding rates and bacterial attachment to these harvested corneal cells. The relationship between myopia progression and peripheral refractive status will also be investigated.
Trial website
Trial related presentations / publications
* Swarbrick H (2012). Do myopia control studies really answer the important clinical questions? Nederlands Contact Lens Congress
* Swarbrick H (2012). Optimising optics and vision through orthokeratology: beyond myopia control. The 3rd Asia Orthokeratology and Specialty Lens Conference
* Kang P, Swarbrick H (2012). Orthokeratology, peripheral refraction and myopia control. 10th Congress of the Orthokeratology Society of Oceania
* Kang P (2012). Future myopia research – where will it take us? 14th International Cornea and Contact Lens Congress
* Watt K, Evans B, Swarbrick H, Eakin P (2012). Phorias and OK. 10th Congress of the Orthokeratology Society of Oceania
* Kang P, Swarbrick H (2011). Peripheral refraction in myopic children wearing OK and GP lenses. Optom Vis Sci 88: 476-82
* Kang P, Swarbrick H (2011). Orthokeratology and peripheral refraction in myopic children. Optom Vis Sci 81:395-403
* Swarbrick H, Alharbi A, Watt K, Lum E (2011). Controlling myopia progression with overnight orthokeratology. Asia-ARVO meeting
* Swarbrick H, Alharbi A, Lum E, Watt K (2011). Overnight orthokeratology for myopia control: short-term effects on axial length and refractive error. British Contact Lens Association
* Swarbrick H, Alharbi A, Lum E, Watt K (2011). Changes in axial length and refractive error during overnight orthokeratology for myopia control. Invest Ophthalmol Vis Sci 52: E-abstract 2829
* Swarbrick H, Alharbi A, Lum E, Watt K (2011). Effects of overnight orthokeratology on axial length and refractive error in progressive myopia. 16th meeting of the The International Society for Contact Lens Research
* Swarbrick H (2011). The science of overnight orthokeratology.Bausch & Lomb Boston Seminar Series
* Kang P (2011). Myopia control with orthokeratology. Corneal and Contact Lens Society of Australia
* Swarbrick H (2010). Research in orthokeratology: balancing risks versus benefits. Global
Specialty Lens Symposium, Las Vegas, Nevada
* Swarbrick H (2010). Latest OK research from the ROK Group. Nederlands Contactlens
Congres, Veldhoven, the Netherlands
* Swarbrick H (2010). Balancing risks vs benefits: the safety of overnight OK. Nederlands
Contactlens Congres, Veldhoven, the Netherlands
* Swarbrick H (2010). Balancing risks and benefits: update on myopia control with OK lenses.
Nederlands Contactlens Congres, Veldhoven, the Netherlands
* Kang P, Swarbrick H (2010). Peripheral Refraction in Myopic Children Wearing OK and GP Contact Lenses. Invest Ophthalmol Vis Sci 51: E-Abstract 3934
* Swarbrick H (2010). ROK Group myopia study update. Eighth Congress of the Orthokeratology Society of Oceania, Gold Coast, Queensland
* Swarbrick HA (2010). Evaluating risks of MK: bacterial binding studies. Eighth Congress of the Orthokeratology Society of Oceania
* Lum E (2010). Are Asian kids OK for OK? Eighth Congress of the Orthokeratology Society of Oceania
* Kang P, Swarbrick H (2010). Peripheral refraction and orthokeratology. Eighth Congress of the Orthokeratology Society of Oceania
*Swarbrick H (2010). Orthokeratology and myopia control. 13th Biennial Scientific Meeting in Optometry
* Gifford, P, Kang P, Swarbrick H (2010). Peripheral refraction and orthokeratology. 13th Biennial Scientific Meeting in Optometry
* Kang P, Swarbrick H (2010). Orthokeratology and peripheral refraction in myopic children. 13th Biennial Scientific Meeting in Optometry
* Swarbrick H (2010). Orthokeratology for myopia control: clinical results. 13th International Cornea and Contact Lens Congress
*Swarbrick H (2010). Managing myopia progression with overnight orthokeratology. Orthokeratology Academy of America Vision By Design 2010 conference
*Swarbrick H (2010). The role of overnight orthokeratology in managing childhood myopia progression. 2nd Asia Orthokeratology and Specialty Lens Conference
* Swarbrick H (2010). The role of overnight orthokeratology in managing childhood myopia progression. TMVC seminar, Annual Meeting of Taiwanese Ophthalmology Society
Public notes

Contacts
Principal investigator
Name 28274 0
Prof Helen Swarbrick
Address 28274 0
School of Optometry and Vision Science, University of New South Wales, Sydney, 2052
Country 28274 0
Australia
Phone 28274 0
+612 9385 4373
Fax 28274 0
Email 28274 0
[email protected]
Contact person for public queries
Name 11431 0
Prof Prof Helen Swarbrick
Address 11431 0
School of Optometry and Vision Science, University of New South Wales, Sydney 2052
Country 11431 0
Australia
Phone 11431 0
+612 9385 4613
Fax 11431 0
+612 9313 6243
Email 11431 0
[email protected]
Contact person for scientific queries
Name 2359 0
Prof Prof Helen Swarbrick
Address 2359 0
School of Optometry and Vision Science, University of New South Wales, Sydney 2052
Country 2359 0
Australia
Phone 2359 0
+612 9385 4373
Fax 2359 0
+612 9313 6243
Email 2359 0
[email protected]

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No Supporting Document Provided



Results publications and other study-related documents

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