OCT Biomarkers for Diabetic Retinopathy

September 5, 2025 updated by: David Huang, Oregon Health and Science University

Functional Optical Coherence Tomography-Derived Biomarkers for Diabetic Retinopathy

Diabetic retinopathy (DR) is caused by changes in the blood vessels of the retina associated with long-term Type 1 or Type 2 diabetes mellitus. DR is a leading cause of blindness in the United States. Standard optical coherence tomography (OCT) cannot directly detect vascular changes, which may occur early affecting the passage of blood through the tiny capillaries (reduced capillary flow) or cause the greatest damage through formation of abnormal blood vessel growth (neovascularization). Currently, fluorescein angiography (FA) is the gold standard for detecting these changes, but FA requires an injection of a dye into the vein of the arm of the patient. This dye can cause undesirable side effects. Recently, OCT has been used to make functional measurements (such as total retinal blood flow among others) and to perform angiography. Thus, functional OCT may provide a useful, alternate way to evaluate diabetic retinopathy.

Study Overview

Status

Active, not recruiting

Conditions

Diabetic Retinopathy

Study Type

Observational

Enrollment (Actual)

165

Contacts and Locations

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

Study Locations

United States
- Oregon
  - Portland, Oregon, United States, 97239
    - Oregon Health & Science University

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

18 years to 79 years (Adult, Older Adult)

Accepts Healthy Volunteers

Yes

Sampling Method

Probability Sample

Study Population

Participants with Type 1 diabetes of greater than 5 years duration OR Type 2 diabetes of any duration. Healthy controls are also being enrolled in this study.

Description

Inclusion Criteria for participants with diabetes:

Male or female participants 18-79 years old
With Type 1 diabetes for over 5 years or Type 2 diabetes of any duration

Exclusion Criteria for participants with diabetes:

Vision worse than 20/200
Inability to maintain fixation for OCT imaging
Significant kidney disease, kidney failure or kidney transplant
Unstable medical status, including blood pressure greater than 180/110 or unstable heart disease
Pregnant or nursing an infant
Presence of an eye disease (other than diabetic retinopathy) that can affect retinal blood flow, retinal permeability or retinal anatomy
Significant cataract, corneal scar, vitreous bleed or other media opacity
History of major eye surgery within 4 months prior to enrollment in this study

Inclusion Criteria for participants without diabetes (controls):

Male or female participants 18-79 years old

Exclusion Criteria for participants without diabetes (controls):

Vision worse than 20/200
Inability to maintain fixation for OCT imaging
Significant kidney disease, kidney failure or kidney transplant
Unstable medical status, including blood pressure greater than 180/110 or unstable heart disease
Pregnant or nursing an infant
Presence of any eye disease that can affect retinal blood flow, retinal permeability or retinal anatomy
Significant cataract, corneal scar, vitreous bleed or other media opacity
History of major eye surgery within 4 months prior to enrollment in this study

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

Number of groups / cohorts

Cohorts and Interventions

Group / Cohort
Group A Patients with: Type 1 or Type 2 diabetes mellitus severe non-proliferative diabetic retinopathy (NPDR) or proliferative diabetic retinopathy (PDR).
Group B Patients with: Type 1 or Type 2 diabetes mellitus with or without mild to moderate NPDR
Group C (controls) Patients without diabetes or evidence of any form of eye disease

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of participants with decreased total retinal blood flow by OCT angiography Time Frame: 1 year	Total retinal blood flow will be measured in uL/min.	1 year
Number of participants with capillary dropout and/or new abnormal retinal blood vessel growth by OCT angiography Time Frame: 1 year	Neovascular membrane area will be measured in mm2.	1 year
Number of participants with measureable macular edema by OCT imaging Time Frame: 1 year	Retinal thickening area will be measured in mm2.	1 year

Collaborators and Investigators

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

Sponsor

Oregon Health and Science University

Investigators

Principal Investigator: Thomas Hwang, MD, Oregon Health and Science University

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)

January 26, 2015

Primary Completion (Actual)

February 24, 2020

Study Completion (Estimated)

December 1, 2026

Study Registration Dates

First Submitted

December 30, 2014

First Submitted That Met QC Criteria