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Protocol Details

Longitudinal Investigation of Dark Adaptation in Participants with Age-Related Macular Degeneration

This study is currently recruiting participants.

Summary | Eligibility | Citations | Contacts




Sponsoring Institute

National Eye Institute (NEI)

Recruitment Detail

Type: Participants currently recruited/enrolled
Gender: Male & Female
Min Age: 50 Years
Max Age: N/A

Referral Letter Required


Population Exclusion(s)



Dark Adaptation;
Age-Related Macular Degeneration (AMD);
Natural History

Recruitment Keyword(s)

Age Related Macular Degeneration;


Age-Related Macular Degeneration

Investigational Drug(s)


Investigational Device(s)




Supporting Site

National Eye Institute


- Age-related macular degeneration (AMD) is a leading cause of vision loss in individuals over 55 years of age. It can cause permanent loss of central vision, which is important for seeing fine details and long distances. AMD has two forms: wet AMD and dry AMD. Most people with AMD have dry AMD. But dry AMD can progress to wet AMD. Wet AMD is the more serious form and can result in severe vision loss.

- A method to identify and monitor the early to middle stages of AMD may help researchers develop new treatments to stop the disease before it becomes severe. In early dry AMD, people cannot see well at night. Researchers want to study whether a procedure that measures how the eye adjusts to the dark can help to identify and monitor early to middle dry AMD.


- To evaluate the effectiveness of using a dark adaptation protocol to identify and monitor early to middle dry age-related macular degeneration.


- People at least 50 years of age who have no AMD. Others who have early to middle dry AMD in at least one eye.


- People will be screened with a physical examination, medical history, blood and urine tests, and a full eye exam.

- This study will last 5 years and require at least 9 visits to NIH. (First visit; study visits at months 3, 6, 12, 18, and 24; and 3 yearly followup visits).

-Up to 10 people will be asked to come back to the clinic 1 week after their first visit. They will be asked to test the device to be used in the study.

- Participants will have baseline exams. These questions will be about problems that affect their eyes under different lighting conditions.

- At every visit, participants will answer questions about general health and current medications (including any vitamins or supplements). They will also have a full eye exam and a 20- to 40-minute test. This test measures how fast the eyes recover in response to decreasing levels of light. The test also measures how sensitive the eyes are to these conditions.

- Participants will continue to have these tests at the yearly followup examinations. They will be treated with the standard of care for any eye conditions they have or may develop during the study.

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Participants will be eligible if the following inclusion criteria are met:

-Participant is able to understand and sign the protocol s informed consent document.

-Participant is able to complete and comply with study assessments for the full duration of the study.

-Participant is greater than or equal to 50 years of age.

-Participant has a BCVA score of greater than or equal to 20/100 (Snellen equivalent) in study eye.

-Participant qualifies for one of the following groups based on AMD grading as defined below.

--Group 0: Participant without AMD defined as no large drusen or advanced AMD in either eye;

--Group 1: Participant has at least one large drusen (greater than or equal to 125 microns) in the study eye and no large drusen or advanced AMD in the fellow eye;

--Group 2: Participant has bilateral large drusen (greater than or equal to 125 microns) with or without retinal pigment epithelial hypo/hyperpigmentary changes;

--Group 3: Participant has at least one large drusen (greater than or equal to 125 microns) in the study eye and advanced AMD in the fellow eye.

--Group 4: Participant has reticular pseudodrusen in the study eye defined as having the presence of RPD on at least one en face imaging method (color photography, autofluorescence or infrared) and (2) confirmation of previously described findings of hyperreflective material located between the RPE and the photoreceptor ellipsoid zone on SD OCT in those areas.


Participants who meet any of the following criteria will be excluded from this study:

-Participant has advanced AMD in the study eye at the baseline visit.

-Participant has other active ocular or macular diseases (e.g., diabetic macular edema, retinal vein occlusion, Stargardt s disease or cone-rod dystrophy) or other known ocular disorders that have caused a visual field deficit (e.g., glaucoma with known visual field defect) in the study eye.

-Participant has a fixation deficit in the study eye that would prevent the participant from performing the AdaptDxTM dark adaptation protocol.

-Participant has a medical condition that the investigator feels would prevent the participant from complying with or being able to complete the study assessments

-Participant had cataract surgery in the study eye within three months prior to enrollment.

-Participant has an oral intake of high doses of vitamin A palmitate supplement (greater than or equal to 10,000 international units (IU) per day).

-Participant has or had hepatitis or liver disease. Abnormally low vitamin A can alter dark adaptation and chronic liver disease has been associated with low vitamin A.

-Participant has a history of vitamin A deficiency.

-Participant is an NEI employee or subordinate or co-worker of an investigator.

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Ferris FL 3rd, Fine SL, Hyman L. Age-related macular degeneration and blindness due to neovascular maculopathy. Arch Ophthalmol. 1984 Nov;102(11):1640-2.

Friedman DS, O'Colmain BJ, Mu(SqrRoot) oz B, Tomany SC, McCarty C, de Jong PT, Nemesure B, Mitchell P, Kempen J; Eye Diseases Prevalence Research Group. Prevalence of age-related macular degeneration in the United States. Arch Ophthalmol. 2004 Apr;122(4):564-72.

Scilley K, Jackson GR, Cideciyan AV, Maguire MG, Jacobson SG, Owsley C. Early age-related maculopathy and self-reported visual difficulty in daily life. Ophthalmology. 2002 Jul;109(7):1235-42.

Grune T, Lietz G, Palou A, Ross AC, Stahl W, Tang G, Thurnham D, Yin SA, Biesalski HK. Beta-carotene is an important vitamin A source for humans. J Nutr. 2010 Dec;140(12):2268S-2285S. Epub 2010 Oct 27.

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Principal Investigator

Referral Contact

For more information:

Emily Y. Chew, M.D.
National Eye Institute (NEI)
NIHBC 10 - CRC BG RM 3-2531
(301) 496-6583

Angel H. Garced, R.N.
National Eye Institute (NEI)
National Institutes of Health
Building 10
Room 10D45
10 Center Drive
Bethesda, Maryland 20892
(301) 594-3141

Office of Patient Recruitment
National Institutes of Health Clinical Center (CC)
Building 61, 10 Cloister Court
Bethesda, Maryland 20892
Toll Free: 1-800-411-1222
Local Phone: 301-451-4383
TTY: TTY Users Dial 7-1-1

Clinical Trials Number:


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