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Optical Defocus to Stimulate Eye Elongation in Hyperopia (ODSEEH)

This study is currently recruiting participants.
Verified December 2015 by Aller, Thomas A., OD
Sponsor:
ClinicalTrials.gov Identifier:
NCT00950924
First Posted: August 3, 2009
Last Update Posted: December 29, 2015
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. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details.
Information provided by (Responsible Party):
Aller, Thomas A., OD
July 30, 2009
August 3, 2009
December 29, 2015
January 2015
June 2017   (Final data collection date for primary outcome measure)
Axial length [ Time Frame: One year ]
Same as current
Complete list of historical versions of study NCT00950924 on ClinicalTrials.gov Archive Site
Refractive Error [ Time Frame: One year ]
Same as current
Not Provided
Not Provided
 
Optical Defocus to Stimulate Eye Elongation in Hyperopia
Use of Multifocal Contact Lenses to Stimulate Axial Elongation in Axial Hyperopia
Axial hyperopia results when the length of the eye is too short for the eye to properly focus distance objects on the retina while the focusing system is relaxed. Emmetropization is the process by which the eye actively adjusts various components of the eye to gradually improve the focus of the eye. Emmetropization frequently involves either an increase or a decrease in the growth of the eye, particularly during infancy and childhood. Numerous animal studies suggest that if an animal is exposed to retinal images located behind the retina either centrally or peripherally, the eye will grow in the direction of the focused image. If an abnormally short eye has resulted in hyperopia, exposing such an eye to retinal images partially located behind the retina might encourage axial elongation, thus reducing the hyperopia.
Hyperopia or farsightedness may cause distance vision and near vision to be blurred. Depending on the severity of the condition and the age of the patient and the status of the binocular vision system, hyperopia can also cause fatigue, asthenopia, headaches, double vision, and amblyopia. Low to moderate amounts of hyperopia rarely cause much difficulty in the young person, but will eventually cause significant near vision problems as the patient ages. Hyperopia can be caused by the eye being too short (axial hyperopia) or by the cornea being too flat or the crystalline lens being to weak (refractive hyperopia). It has been established by the PI that axial growth can be dramatically lessened in children and adolescents with myopia through the use of bifocal contact lenses prescribed in a particular way (The CONTROL Study). Studies by Earl Smith, O.D., Ph.D. have suggested that multi-zonal contact lenses that provide proper axial focus while manipulating peripheral defocus can either discourage or encourage axial growth to treat myopia or hyperopia respectively. In the present study, simultaneous vision bifocal soft contact lenses will be used to encourage axial growth in hyperopic children and adolescents with axial hyperopia in an effort to reduce hyperopia. Subjects will be randomly assigned to wear either bifocal soft contact lenses or single vision soft lenses. The bifocal contact lenses will be prescribed to provide for clear central vision at both distance and near with the near zone of the contact, thus exposing the retina to hyperopic defocus from the distance zone.
Interventional
Not Provided
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple (Participant, Care Provider, Investigator)
Primary Purpose: Treatment
  • Hyperopia
  • Refractive Error
  • Device: Simultaneous Vision Bifocal Soft Contact Lenses
    Simultaneous Vision Bifocal Soft Contact Lenses will be prescribed such that the distance vision as measured by manifest subjective refraction will be properly corrected by the near vision add power and undercorrected by the distance power.
  • Device: Single Vision Soft Contact Lenses
    Single vision soft contact lenses will be prescribed to properly correct the distance vision as measured by manifest subjective refraction.
  • Experimental: Bifocal Contact Lenses
    Simultaneous Vision Bifocal Soft Contact Lenses will be prescribed such that the distance vision as measured by manifest subjective refraction will be properly corrected by the near vision add power and undercorrected by the distance power.
    Intervention: Device: Simultaneous Vision Bifocal Soft Contact Lenses
  • Placebo Comparator: Single Vision Soft Contact Lenses
    Subjects will be fitted with single vision soft contact lenses with goal of corrected emmetropia at a distance of 20 feet.
    Intervention: Device: Single Vision Soft Contact Lenses
Not Provided

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
 
Recruiting
30
September 2017
June 2017   (Final data collection date for primary outcome measure)

Inclusion Criteria:

  • Aged 5-12
  • Hyperopia > +1.25 each eye (cycloplegic refraction)
  • Ability to wear soft contact lenses

Exclusion Criteria:

  • Amblyopia
  • Strabismus
  • Astigmatism > 1.00 diopters
  • Axial Length > 24.00 mm
Sexes Eligible for Study: All
5 Years to 12 Years   (Child)
Yes
Contact: Thomas A Aller, O.D. 6508711816 cptreyes@earthlink.net
United States
 
 
NCT00950924
Not Provided
Yes
Not Provided
Not Provided
Aller, Thomas A., OD
Aller, Thomas A., OD
Not Provided
Principal Investigator: Thomas A Aller, O.D. Unafilliated
Aller, Thomas A., OD
December 2015

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