Defocus Induced Changes on Choroidal Thickness

NCT ID: NCT03954886

Last Updated: 2022-03-17

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 48 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2018-05-15
• Study Completion Date: 2021-12-31

Brief Summary

The goals of this study are to assess the short-term (10-60 minutes) effects of different magnitudes of myopic and hyperopic optical defocus on the transient thickness of the choroid in children and adults, as well as to assess the recovery period. Choroidal thickness will be measured non-invasively following 10-60 minutes of monocular exposure to -5 diopters to +5 diopters of optical defocus induced by spectacle lenses. The hypothesis is that choroidal thickness will increase with increasing myopic defocus and decrease with increasing hyperopic defocus. The relationship between the magnitude of defocus and the magnitude and direction of choroidal thickness change will be assessed.

Detailed Description

The purpose of this study is to determine modifying factors inducing or protecting against the development or progression of myopia, or nearsightedness. Myopia has reached epidemic levels in urbanized countries, reaching up to 90% of the teenage and young adult population in urban Asia. Myopia represents a significant socioeconomic burden and poses a risk for associated ocular diseases such as retinal detachment, choroidal neovascularization, and glaucoma. The economic and public health burden of myopia are growing disproportionately to the population, spurring interest in the development of therapies to prevent occurrence or progression. Myopia generally occurs because the eye grows too long, with onset and progression occurring from about ages 6 to 20. Though much is known about factors that influence eye growth, the exact mechanisms by which they do so have not been elucidated.

The goals of this study are to assess the short-term (10-50 minutes) effects of different magnitudes of myopic and hyperopic optical defocus on the transient thickness of the choroid in children and adults, as well as to assess the recovery period. Choroidal thickness will be measured non-invasively following 10-50 minutes of monocular exposure to -5D to +5D of optical defocus induced by spectacle lenses. The hypothesis is that choroidal thickness will increase with increasing myopic defocus and decrease with increasing hyperopic defocus. The relationship between the magnitude of defocus and the magnitude and direction of choroidal thickness change will be assessed.

Conditions

Induced Defocus to the Retina

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: SINGLE_GROUP
• Primary Study Purpose: BASIC_SCIENCE
• Blinding Strategy: NONE

Study Groups

Induced myopic defocus

Subjects will view a television through a lens that induces blur to the retina for one hour. Images of the eye will be captured every 10 minutes

Group Type: EXPERIMENTAL

Plus powered optical lens

Intervention Type: DEVICE

A plus powered optical lens will be placed in front of one eye.

No defocus

Subjects will view a television through a lens that induces no blur to the retina for one hour. Images of the eye will be captured every 10 minutes

Group Type: NO_INTERVENTION

No interventions assigned to this group

Interventions

Plus powered optical lens

A plus powered optical lens will be placed in front of one eye.

Intervention Type: DEVICE

Eligibility Criteria

Inclusion Criteria

• 6 to 45 years of age (preliminary studies indicate that children under 6 cannot sit for imaging, and subjects over 45 do not respond to the optical defocus with expected choroidal thickness changes)
• Best corrected visual acuity of 20/25 or better in better-seeing eye

Exclusion Criteria

• Age younger than 6 years or older than 45
• Best corrected visual acuity worse than 20/25 in better-seeing eye
• Ocular pathology or prior ocular injury
• Heavily-pigmented choroid that precludes accurate measurement of choroidal thickness

• Minimum Eligible Age: 6 Years
• Maximum Eligible Age: 45 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

University of Houston

OTHER

Sponsor Role: lead

Responsible Party

Lisa Ostrin

Assistant Professor

Responsibility Role: PRINCIPAL_INVESTIGATOR

Locations

University of Houston College of Optometry

Houston, Texas, United States

Countries

United States

Other Identifiers

STUDY00000852

Identifier Type: -

Identifier Source: org_study_id