Rod and Cone Mediated Function in Retinal Disease

August 28, 2026 updated by: National Eye Institute (NEI)

Background:

Retinal diseases cause the loss of rod and cone photoreceptors. Symptoms include vision loss and night blindness. Researchers want to learn about rod and cone function in healthy people and people with retinal disease. They want to know if how well a person sees in the dark can test the severity of retinal disease.

Objectives:

To find out if how well a person sees in the dark can test the severity of retinal disease. To find out if this can help detect retinal disease and track its changes.

Eligibility:

People ages 5 and older with:

Retinal disease OR

20/20 vision or better with or without correction in at least one eye

Design:

Participants will be screened with medical and eye history and eye exam. Those with retinal disease will also have:

Eye imaging: Drops dilate the eye and pictures are taken of it.

Visual field testing: Participants look into a bowl and press a button when they see light.

Electroretinogram (ERG): An electrode is taped to the forehead. Participants sit in the

dark with their eyes patched for 30 minutes. Then they get numbing drops and contact

lenses. Participants watch lights while retina signals are recorded.

Visit 1 will be 3-8 hours. Participants will have up to 6 more visits over 6-12 months. Visits include:

Eye exam and imaging

Time course of dark adaptation: Participants view a background light for 5 minutes then

push a button when they see colored light.

Dark adapted sensitivity: Participants sit in the dark for 45 minutes. They push a button when

they see colored light.

For participants with retinal disease, ERG and visual field testing

Study Overview

Status

Recruiting

Conditions

Detailed Description

Objective: The objective of this protocol is to investigate local changes in rod and cone photoreceptor function across the retina in healthy volunteers and participants with retinal disease.

Study Population: Up to 250 healthy volunteers and 250 participants, age five or older, with retinal disease.

Design: This single-center, observational, case-control study will be comprised of three related Aims that assess rod and cone function with commercial perimeters and/or a commercial Cambridge Research Systems computer monitor (Display++) specialized for displaying stimuli at low light intensities. For Aim 1 the normal retinal sensitivity ranges will be established for both fundus-guided and non-guided perimeters. For Aim 2, the normal range for describing the kinetics of dark adaptation following bleaching of retinal rhodopsin will be established for the fundus-guided and non-guided perimeters. For Aim 3, local changes in rod and cone photoreceptor function across the retina in participants with retinal disease will be examined from measurement of the kinetics of dark adaptation, scotopic and photopic retinal sensitivity, and/or Radial Frequency (RF) hyperacuity on the Display++ monitor. Testing may also include patient reported outcome (PRO) questionnaires to assess vision problems under low luminance conditions. For Aim 4, a subset of retinal disease participants (approximately 40) will complete two electroretinogram (ERG) sessions to develop a scaling factor to allow comparison with historical clinical data. The scaling factor will be used in the NEI ophthalmology clinic to account for changes in ERG parameters in patients tested using the current system compared to older clinical results.

Outcome Measures: The primary outcome for this study is to establish normal ranges for A) the kinetics of dark adaptation (time), B) retinal sensitivity (dB) for the fundus-guided and non-guided perimeters, and C) RF hyperacuity on the Display++ monitor. The secondary outcomes will be to examine changes in the kinetics of dark adaptation, scotopic and photopic retinal sensitivity, and/or RF hyperacuity in participants with retinal disease and potentially correlate these clinical measures with patients self-reported evaluation of their vision under low luminance conditions. An exploratory outcome will be to define a scaling factor for ERGs recorded with the RM electrode on the MonCV electrophysiology systems (MonCvONE and MonPackONE, Metrovision France) with the ERG data previously recorded with the Burian-Allen (BA) electrode on the commercial UTAS(TM) electrophysiology system.

Study Type

Observational

Enrollment (Estimated)

500

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Study Locations

    • Maryland
      • Bethesda, Maryland, United States, 20892
        • Recruiting
        • National Institutes of Health Clinical Center

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

5 years and older (Child, Adult, Older Adult)

Accepts Healthy Volunteers

Yes

Sampling Method

Non-Probability Sample

Study Population

Up to 250 participants with retinal disease will be enrolled and up to 120 healthy volunteers will be enrolled.

Description

  • INCLUSION CRITERIA:
  • Participant must be five years of age or older.
  • Participant (or legal guardian) must understand and sign the protocol s informed consent document.
  • Participant must be able to cooperate with the testing required for this study.

For Participants with retinal disease only:

  • Participant must have retinal disease, defined as evidence of loss of retinal dysfunction and/or degeneration as established by standard clinical methods including perimetry, ERG and imaging.
  • Participant must have a measurable visual acuity.

For Healthy Volunteers only:

-Participant must have visual acuity of 20/20 or better, with or without correction (e.g., glasses or contact lens) in at least one eye.

EXCLUSION CRITERIA:

-Participant with changes in pre-retinal media sufficient to obscure a view of the retina.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Observational Models: Case-Control
  • Time Perspectives: Cross-Sectional

Cohorts and Interventions

Group / Cohort
Affected
Participants with retinal disease
Unaffected
Healthy volunteers

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
The primary outcomes for this study are to establish normal ranges for the kinetics of dark adaptation and dark-adapted retinal sensitivity for the fundus guided and non-guided perimeters and for RF hyperacuity on the Display++.
Time Frame: ongoing, up to 10 visits in 5 years
The primary outcomes for this study are to establish normal ranges for the kinetics of dark adaptation and dark-adapted retinal sensitivity for the fundus guided and non-guided perimeters and for RF hyperacuity on the Display++.
ongoing, up to 10 visits in 5 years

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Secondary outcomes will be to examine changes in the kinetics of dark adaptation and dark-adapted retinal sensitivity, and scotopic and photopic RF hyperacuity in participants with retinal disease.
Time Frame: ongoing, up to four visits in 5 years
Secondary outcomes will be to examine changes in the kinetics of dark adaptation and dark-adapted retinal sensitivity, and scotopic and photopic RF hyperacuity in participants with retinal disease.
ongoing, up to four visits in 5 years

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Investigators

  • Principal Investigator: Brett G Jeffrey, Ph.D., National Eye Institute (NEI)

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

March 24, 2016

Primary Completion (Estimated)

December 30, 2029

Study Completion (Estimated)

December 30, 2029

Study Registration Dates

First Submitted

November 28, 2015

First Submitted That Met QC Criteria

November 28, 2015

First Posted (Estimated)

December 1, 2015

Study Record Updates

Last Update Posted (Actual)

August 31, 2026

Last Update Submitted That Met QC Criteria

August 28, 2026

Last Verified

August 18, 2026

More Information

Terms related to this study

Other Study ID Numbers

  • 160024
  • 16-EI-0024

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

UNDECIDED

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.