An observational study in Age-related Macular Degeneration and Aging, sponsored by Cynthia Owsley. Completed at 1 site in United States. Open to participants aged 20 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-09-26.
Sponsored by Cynthia Owsley · Observational
Delayed rod-mediated dark adaptation (RMDA), or delayed recovery of vision in a dark environment, is a functional biomarker (i.e., risk factor) for early age-related macular degeneration (AMD). This research plan is designed to elucidate the structural (anatomical) basis of this visual deficit using cellular- and subcellular level imaging of the retina and its supporting tissues in living people. An accurate map and timeline of structure-function relationships in persons tested for night vision will result in functionally validated structural endpoints for early AMD trials, as well as define major biologic effects for development into future treatments.
The Alabama Study on Early Age-Related Macular Degeneration 2 (ALSTAR2) is a prospective cohort study with baseline measurements that are repeated at follow-up 3 years later. The baseline and 3 year follow-up visits will each consist of 2 visits for a total of 4 visits.
Study assessments are listed below. All are collected at two visits at both baseline and follow-up for 4 visits total (blood collection for DNA analysis at baseline only). For some functional tests (photopic and mesonic acuity, photopic and mesonic contrast sensitivity), each eye will be tested separately. For other functional tests (dark-adapted two-color perimetry, light-adapted cone-mediate perimetry, rod-mediated dark adaptation), only one eye will be tested, which will be designated by the study eye. Tropicamide 1% and phenylephrine hydrochloride 2.5% are used to dilate pupils (diameter of ≥ 6 mm) as needed for specific parts of the protocol. After completing the baseline visits, participants will receive an annual phone call from the study coordinator so that contact information can be updated. Participants will receive an annual newsletter containing study related information (this will be submitted to the IRB for approval).
Study Assessments:
The Young normal group will only complete:
1,459 studies on the registry are indexed under Macular Degeneration; 238 are open to participants now.
This study's enrollment of 556 is above the median of 110 across 409 observational studies indexed under Macular Degeneration.
Browse Macular Degeneration studies →This is the only study on the registry with Cynthia Owsley as lead sponsor.
Counted across the registry records on this site, refreshed daily.
group 1 is >=60 years old with normal macular health group 2 is >=60 years old with early AMD group 3 is 20-30 years old are Young Normals
Inclusion Criteria:
For those in Normal Macular Health or Early AMD: aged ≥ 60 years; either have normal macular health in both eyes at baseline or have early AMD in one eye For Young Normals: aged 20-30 years old; normal macular health in both eyes.
Exclusion Criteria:
Exclusion for those in normal macular health are:
Exclusion criteria for the early AMD group:
These are identical to those described above, except that it is acceptable for participants to have early AMD (AREDS 2-4) in one eye and be AREDS grade 1 or any stage of AMD in the fellow eye.
Exclusion for Young Normals:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
\>=60 years old with no macular disease
Other: Normal Macular Health
\>=60 years old with early age-related macular degeneration
Other: Early Macular Degeneration
20-30 years old with normal macular health
Other: Young Normals
This group of participants will have function assessed using rod- and cone-mediated tests (rod-mediated dark adaptation, 2 color dark adapted perimetry, cone-mediated perimetry, photopic and mesopic acuity, photopic and mesopic contrast sensitivity). Age-related macular degeneration status will be determined by multi-modal imaging.
This group of participants will have function assessed using rod- and cone-mediated tests (rod-mediated dark adaptation, 2 color dark adapted perimetry, cone-mediated perimetry, photopic and mesopic acuity, photopic and mesopic contrast sensitivity). Age-related macular degeneration status will be determined by multi-modal imaging.
This group of participants will have function assessed using rod- and cone-mediated tests (rod-mediated dark adaptation, 2 color dark adapted perimetry, cone-mediated perimetry, photopic and mesopic acuity, photopic and mesopic contrast sensitivity). Age-related macular degeneration status will be determined by multi-modal imaging.
Rod-mediated dark adaptation
Time required to recover light sensitivity after exposure to bright light
Time frame: Measured at baseline enrollment
Rod-mediated dark adaptation
Time required to recover light sensitivity after exposure to bright light
Time frame: Measured at 3 years after baseline enrollment
incident age-related macular degeneration (AMD) or progression of AMD using multimodal imaging
development of AMD or progression of AMD at the 3 year follow up visit
Time frame: Measured at baseline enrollment
incident age-related macular degeneration (AMD) or progression of AMD using multimodal imaging
development of AMD or progression of AMD at the 3 year follow up visit
Time frame: Measured at 3 years after baseline enrollment
Light sensitivity as measured by microperimetry and perimetry
Amount of light needed to detect a small target object
Time frame: Measured at baseline enrollment
Light sensitivity as measured by microperimetry and perimetry
Amount of light needed to detect a small target object
Time frame: Measured at 3 years after baseline enrollment
Photopic and mesopic acuity
Visual acuity under day time and twilight conditions
Time frame: Measured at baseline enrollment
Photopic and mesopic acuity
Visual acuity under day time and twilight conditions
Time frame: Measured at 3 years after baseline enrollment
Photopic and mesopic contrast sensitivity
Amount of contrast needed to recognize a letter under day time and twilight conditions
Time frame: Measured at baseline enrollment
Photopic and mesopic contrast sensitivity
Amount of contrast needed to recognize a letter under day time and twilight conditions
Time frame: Measured at 3 years after baseline enrollment
Plan to share: No — Currently there is no plan to make individual participant data available to other researchers.
This study is completed, as verified in Jun 2025. You cannot join it, but the record below documents what was studied.
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