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Diagnostic Innovations in Glaucoma Study (DIGS)

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ClinicalTrials.gov Identifier: NCT00221897
Recruitment Status : Recruiting
First Posted : September 22, 2005
Last Update Posted : July 6, 2021
National Eye Institute (NEI)
Information provided by (Responsible Party):
Linda Zangwill, University of California, San Diego

Brief Summary:

The overarching goal of our research study is to evaluate changes in visual function and optic nerve topography (the structure of the back of the eye) in patients with glaucoma (increased susceptibility to pressure inside the eye that can cause loss of vision) or those with an increased risk of developing the disease. The purpose of this study is to determine the best methods for detecting the presence or progression (worsening over time) of glaucoma in patients with and without myopia and its effects on daily and visual function and quality of life. With several sources of NIH and foundation funding over the last twenty years we have designed a robust research protocol to address the most challenging aspects of glaucoma management. The most recent focus of this research is 1) to improve our ability to detect open angle glaucoma in individuals with myopia and in individuals of European and African descent, 2) to determine whether monitoring of the retinal vasculature with new optical imaging instruments can improve glaucoma management and elucidate the pathophysiology of the disease, and 3) to differentiate between age-related changes and glaucomatous progression.

The grants supporting this project include 3 NIH funded studies, 1) the University of California, San Diego UCSD -based "Diagnostic Innovations in Glaucoma Study" (DIGS funded since 1995): 2) the "African Descent and Glaucoma Evaluation Study" (ADAGES funded since 2002), 3) the Brightfocus Foundation National Glaucoma Research Program and 4) the UCSD-based "Diagnosis and Monitoring of Glaucoma with Optical Coherence Tomography Angiography" (funded since 2018). The ADAGES is a multi-center study with data collection also conducted at 2 other academic sites, the University of Alabama at Birmingham, and Columbia University.

Enrolled healthy participants, glaucoma suspects and glaucoma patients are generally asked to return for two or more visits a year for several years. We then analyze whether the glaucoma patients are progressing and what factors influence their glaucoma status compared to healthy subjects and individuals suspected of having glaucoma.

Condition or disease
Primary Open Angle Glaucoma Myopia

Detailed Description:

The Diagnostic Innovation in Glaucoma Study (DIGS) and ADAGES are longitudinal studies in which participants with or without myopia are examined approximately biannually, in most cases. Healthy controls with or without myopia are examined once, in most cases. The ADAGES recruitment and testing of individuals of African descent is an independently funded multi-center (including UCSD, Columbia University, and University of Alabama, Birmingham) study, which follows the same study protocol as the DIGS to ensure that the data from both studies can be analyzed together. This harmonization of protocols leverages the advantages of both DIGS by increasing the sample sizes to address the unique hypotheses of each study.

All participants must be 18 years old or older. Participants with or without myopia will be required to have at least one eye with open angles, best corrected visual acuity of 20/40 or better to be included. Participants taking a medication known to affect visual field sensitivity and eyes with a history of intraocular surgery (except uncomplicated glaucoma and cataract surgery), a secondary cause of elevated intraocular pressure, a coexisting intraocular disease affecting visual field, or a problem other than glaucoma affecting color vision may be excluded.

Most of the extensive testing completed for these visits can be considered standard of care, but for clinical care all tests are not generally all done at the same patient visit with the variety of instruments included in this research project. The following tests can be considered standard of care: medical history, blood pressure and heart rate, height and weight, visual acuity testing near acuity testing, low contrast sensitivity testing, slit lamp biomicroscopy (including gonioscopy), measurements of intraocular pressure with contact and non-contact tonometry, corneal thickness measurement (pachymetry), corneal elasticity measured using non-contact tonometry, interocular axial length, corneal curvature, anterior chamber depth measurements (all measured using intraocular lens IOL master), dilated fundoscopy, stereoscopic ophthalmoscopy of the optic disc with a 78 D lens, color vision testing, standard automated perimetry, optical coherence tomography (OCT) and photography.

There is currently no end date to the study, as the follow-up will continue as long as the research is supported.

The time involved is usually 2-4 visits per year of approximately 2-5 hours each.

DIGS Positional Study Subjects will also be given the opportunity to participate in the following additional auxiliary study. The DIGS Positional Study will allow subjects to participate in an ancillary study. Participation in this ancillary study includes imaging of the eyes using Optical Coherence Tomography (OCT) and Optical Coherence Tomography Angiography (OCT-A), as well as measurement of intraocular pressure (IOP) and blood pressure (BP) in sitting and supine positions. No invasive procedures or treatments will be administered. We will be using the standard clinically available software as well as investigational software available for research purposes. The investigational software has been deemed safe by the manufacturer of the device and does not pose any additional risks to patients. Since not every glaucoma patient has high eye pressure (low-tension glaucoma) or has pressure controlled with medication use (so that the untreated eye pressure is now known), glaucoma subjects using intraocular pressure lowering medication and with IOP < 25 mm Hg may be requested to stop their medication for 1 to 3 weeks, by the treating ophthalmologist depending on the class of medication, before being imaged. Risks are small and include IOP elevation. However, glaucoma progression is on the order of months to years, and not days. Subjects will resume using the medication after the research visit is completed.

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Study Type : Observational
Estimated Enrollment : 3000 participants
Observational Model: Cohort
Time Perspective: Prospective
Official Title: Diagnostic Innovations in Glaucoma Study
Study Start Date : April 1995
Estimated Primary Completion Date : July 2022
Estimated Study Completion Date : July 2022

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Glaucoma

Healthy individuals
healthy controls with or without myopia
Persons at risk for or with primary open angle glaucoma
with or without myopia with a diagnosis of glaucoma, glaucoma suspect and ocular hypertension

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Sampling Method:   Non-Probability Sample
Study Population


  • Subjects are healthy controls with or without myopia, and patients with or without myopia with a diagnosis of glaucoma, glaucoma suspect and ocular hypertension
  • They will be considered if they are above 18 years old.
  • There is no upper age limit
  • Subject are not restricted by gender, race or ethnicity.


-Participants with other ocular or systemic conditions and treatment, which may affect visual function, are excluded.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00221897

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Contact: Eunice Williams-Steppe, MA 858-822-1133 ewsteppe@glaucoma.ucsd.edu

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United States, California
UCSD, Hamilton Glaucoma Center Recruiting
La Jolla, California, United States, 92093-0946
Contact: Eunice Williams-Steppe, MA    858-822-1133    ewsteppe@glaucoma.ucsd.edu   
Principal Investigator: Linda M Zangwill, PhD         
Principal Investigator: Robert N Weinreb, MD         
Sub-Investigator: Christopher Bowd, PhD         
Principal Investigator: Andrew Camp, MD         
Sponsors and Collaborators
University of California, San Diego
National Eye Institute (NEI)
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Principal Investigator: Linda Zangwill, PhD University of California, San Diego
Additional Information:
Publications of Results:
Weinreb R.N. and Greve E.L. (Eds.). (2004). Glaucoma diagnosis. Structure and function. The Hague, The Netherlands: Kugler Publications.

Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):

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Responsible Party: Linda Zangwill, Principal Investigator, University of California, San Diego
ClinicalTrials.gov Identifier: NCT00221897    
Other Study ID Numbers: EY08208; EY11008, EY027510
R01EY027510 ( U.S. NIH Grant/Contract )
First Posted: September 22, 2005    Key Record Dates
Last Update Posted: July 6, 2021
Last Verified: July 2021
Keywords provided by Linda Zangwill, University of California, San Diego:
Primary open angle glaucoma
Nerve Fibers/pathology
Risk factors glaucoma
Additional relevant MeSH terms:
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Glaucoma, Open-Angle
Ocular Hypertension
Eye Diseases