MedPath

AMD and Validation Rod-Meditated Dark Adaptation With Everyday Task Performance

Not Applicable
Not yet recruiting
Conditions
Age-Related Macular Degeneration
Interventions
Diagnostic Test: Streetlab VR
Registration Number
NCT06619405
Lead Sponsor
Duke University
Brief Summary

The goal is to conduct a cross-sectional, single timepoint study on older adults with early and intermediate AMD, and with subretinal drusenoid deposits (SDD), and those in normal health, establishing an association between dark adaptation and reading performance under dim illumination, both which depend on rod photoreceptors.

Detailed Description

The investigators propose two sites for the study, Duke University and UAB. Each site will enroll 100 participants as indicated in the table above, per the AREDS 9-step AMD classification system, with 200 participants in the sample. Because the variance of rod-mediated dark adaptation in AMD patients increases with increasing disease severity, the investigators will implement a larger sample size for intermediate AMD and a smaller sample for patients in normal macular health.

The investigators will collect demographic characteristics (age, race/ethnicity, gender), ocular medical history from the electronic health record, and medication use. In addition, the protocol will focus on measuring the following major components:

1. Comprehensive eye exam

2. Rod-mediated dark adaptation

3. Reading performance

4. Mobility

5. Ellipsoid zone loss and attenuation

Statistical associations will be computed using correlational analysis for the overall sample, within each patient group, and also separately for those with SDD. Sample size estimation is challenging because there is no previous literature on the association between rod-mediated dark adaptation and MNREAD reading performance or MOST performance. With a sample size of 200 participants, the investigators will have adequate statistical power (80%) to detect a correlation of at least 0.20 for the total sample and adequate statistical power to detect within-group correlations of at least 0.40.

Recruitment & Eligibility

Status
NOT_YET_RECRUITING
Sex
All
Target Recruitment
100
Inclusion Criteria
  • Capable and willing to provide consent
  • Has been diagnosed with early, intermediate dry age-related macular degeneration or geographic atrophy or has a healthy macular for controls
  • At least 50 years of age
Exclusion Criteria
  • Unable or unwilling to give consent or unable to read consent since the study involves testing which requires reading
  • Under 50 years of age
  • Presence of dense cataracts in the study eye (s) that can affect visual function tests
  • Presence of glaucoma requiring treatment during the study and/or visual field defects
  • Previous retinal laser or surgical therapy in the study eye(s)
  • Previous retinal laser or surgical therapy in the study eye(s)
  • Any other ocular condition requiring long-term therapy or surgery during the study
  • The participant has photographically significant corneal or media opacities in either eye that would preclude adequate ophthalmic imaging and functional testing
  • Diagnosis of nystagmus that will interfere with testing
  • High myopia -8 Diopters or more severe
  • The participant has, in the opinion of the Investigator, any physical or mental condition that would increase the risk of participation in the study or may interfere with the study procedures, evaluations, and outcome assessments.

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Arm && Interventions
GroupInterventionDescription
Early AMDStreetlab VRStudy patients who have a diagnosis of early AMD
Intermediate AMDStreetlab VRStudy patients who have a diagnosis of Intermediate AMD
Geographic AtrophyStreetlab VRStudy patients who have a diagnosis of Geographic Atrophy
AMD ControlsStreetlab VRStudy patients who have healthy eyes
Primary Outcome Measures
NameTimeMethod
Total number of participants with total ellipsoid zone (EZ) band attenuationApproximately 2 years

Total EZ attenuation is defined as EZ-RPE (retinal pigment epithelium) thickness = 0 μm.

Secondary Outcome Measures
NameTimeMethod
Total number of participants with partial ellipsoid zone (EZ) band attenuationApproximately 2 years

Partial EZ attenuation is defined as EZ-RPE (retinal pigment epithelium) thickness ≤ 20 μm.

Rod-mediated dark adaptationSingle visit, approximately 5-6 hours

Measured for right and left eyes separately using the AdaptDx, a computerized dark adaptometer.

Reading performance as measured by the MNREAD (Minnesota low vision reading) chartSingle visit, approximately 5-6 hours

Reading performance will be assessed binocularly with the MNREAD iPad app on a digital version of the MNREAD chart. The MNREAD is a text based chart used to measure near visual acuity in people with normal or low vision.

Mobility as measured by the Mobility Standardized Test (MOST)Single visit, approximately 5-6 hours

The MOST task involves walking through a maze which can be performed under a range of mesopic and photopic conditions. Scoring is automatically computed based on the duration and mobility errors, which generated a score from 0 to 100, with 100 as the best performance.

Trial Locations

Locations (1)

Duke Eye Center

🇺🇸

Durham, North Carolina, United States

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