Bifocal Soft Contact Lenses and Their Effect on Myopia Progression in Children and Adolescents.

Not Applicable

Completed

• Conditions: Fixation Disparity; Myopia; Esophoria
• Interventions: Device: Bifocal Contact Lenses; Device: Placebo Control

• Registration Number: NCT00214487
• Lead Sponsor: Aller, Thomas A., OD

Brief Summary

The purpose of this study is to determine whether bifocal soft contact lenses are effective in controlling the progression of myopia in children and adolescents that exhibit a tendency to excessively cross their eyes while reading (esophoria or eso fixation disparity). Several studies have demonstrated that bifocal or progressive multifocal spectacles are effective in slowing the progression of myopia in children either with near point esophoria and/or with inadequate focusing at near. A prominent theory for one cause of myopia progression is that poorly focused images on the back of the eye (retina) cause the eye to lengthen, causing an increase in myopia. Bifocal contact lenses may reduce this retinal defocus, reducing the stimulus to eye elongation, and thus may reduce myopia progression.

Detailed Description

Myopia has become the focus of growing attention and concern because the prevalence of myopia appears to increasing in some populations (reaching 90% for some university student populations in Asia). There are serious risks to higher levels of myopia, including cataracts, glaucoma, retinal detachment and myopic retinal degeneration. Several studies have shown mild to moderate control of myopia progressionwith bifocal or multifocal spectacles in children with esophoria at near and/or with accommodative deficiencies. Pilot studies by the P.I. have suggested that bifocal contact lenses may control myopia progression in children with near point eso fixation disparity.

CONTROL is a controlled, randomized, prospective, double-blind, one year study of the changes in myopia in 80-90 subjects from age 8-18 with low to moderate levels of myopia, low levels of astigmatism, and eso fixation disparity at near, when fitted with either bifocal soft contact lenses or single vision soft contact lenses. The primary outcome measures will be cycloplegic refraction and axial length measures.

Study Timeline

• Study Start: 2003-10
• Study First Submitted: 2005-09-14
• Study First Submitted QC: 2005-09-14
• Study First Posted: 2005-09-22
• Primary Completion: 2006-03
• Study Completion: 2006-03
• Status Verified: 2014-06
• Results First Submitted: 2014-06-23
• Results First Submitted QC: 2014-06-23
• Last Update Submitted: 2014-06-23
• Results First Posted: 2014-07-22
• Last Update Posted: 2014-07-22

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 78

Inclusion Criteria

• Myopia between -0.50 and -6.00
• Eso fixation disparity at 33cm with distance correction
• Astigmatism 1.00 or less
• Ability to wear soft contact lenses

Exclusion Criteria

• Presence of ocular disease preventing wear of contacts
• Pregnancy or nursing
• Use of certain medications

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Bifocal Contact Lenses	Bifocal Contact Lenses	Use of bifocal contact lenses to control the progression of myopia
Control	Placebo Control	Single vision soft contact lenses

Primary Outcome Measures

Name	Time	Method
Changes in Cycloplegic Autorefraction in One Year.	One year

Secondary Outcome Measures

Name	Time	Method
Keratometric Changes at One Year.	One year
Changes in Manifest Refraction at One Year.	One year
Relationship Between Residual Fixation Disparity and Myopia Progression.	One year
Changes in Cycloplegic Subjective Refraction in One Year	One year
Changes in Axial Length at One Year.	One year