Quantitative Assessment and Characterization of Microvascular Function Using Diffuse Optical Tomography (DOT)

May 10, 2022 updated by: Sheffield Teaching Hospitals NHS Foundation Trust

Quantitative Assessment and Characterization of Microvascular Function Using Diffuse Optical Tomography Version

Atherosclerosis is accompanied by microvascular dysfunction (an impairment of blood vessels to dilate or constrict in response to demand). The ability to reliably measure microvascular dysfunction would help identify patients at risk of myocardial infarction and test new treatments. All existing measures of microvascular dysfunction suffer significant limitations.

Near Infrared Spectroscopy (NIRS) is an imaging method that uses an infrared light-source and detector (called optodes) to painlessly shines light into tissue and collect reflected light at different wavelengths. This data allows quantification of the amount of haemoglobin (blood) in the tissue and whether it is oxygenated or de-oxygenated.

Diffuse optical tomography (DOT) is a powerful analysis technique for data collected from multiple NIRH optodes. Unlike most NIRS studies that use a single pair of optodes and collects a single datapoint for each wavelength over time, DOT allows three-dimensional spatial reconstruction of haemodynamic and anatomic changes in a large region of tissue over time.

In preliminary work DOT had the potential to measure forearm reactive hyperaemia, a key indicator of microvascular function. Team will test whether DOT can detect differences between patients and healthy volunteers.

In this work, 30 patients will be recruited with type 2 diabetes, 30 patients who have had a previous myocardial infarction and 30 healthy volunteers. The Investigator will also recruit 50 patients who are on waiting lists for coronary angiography.

The DOT will be used to measure participants' microvascular function after brachial artery occlusion by a blood pressure cuff. The Investigator will then examine whether DOT can detect differences between healthy volunteers, diabetics, and patients with a previous heart attack, and whether DOT is able to predict existence of coronary artery disease on angiography. If successful, DOT can be developed for assessment of microvascular function to the point where it could be applied to clinical studies.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

Previous pilot studies have shown ability to collect promising data safely. In the following studies, the same study as in the pilot will be performed to apply the array of optodes to the surface of the arm. These emit light painlessly into the tissue and collect scattered light from the tissue. Inflation of a blood pressure cuff around the arm for 5 minutes, then deflate the cuff to allow blood flow back into the tissue. From the data gathered before, during and after the cuff is inflated, 3D reconstructions can be performed of HbO, HbR, and HbT changes in the forearm during and after arterial occlusion.

Study 1) Can DOT detect differences in vascular function between healthy volunteers and patients with proven heart disease or diabetes

This study will measure vascular function in patients with known heart disease (previous myocardial infarction) or diabetes and compare this to matched healthy volunteers. This will establish whether DOT can detect differences in vascular response between these groups. If so, then the method has the potential to be useful diagnostically or prognostically.

Potential participants will be approached by poster, or face to face in STH clinics and provided with the information sheet which participants will be asked to read at home. Participants will be given the opportunity to ask questions by email or telephone at any time afterwards. Participants will be asked to contact us if they are willing to participate.

Participants will be booked with an appointment to attend the Clinical Research Facility at Sheffield Teaching Hospitals (at least 24hrs after receiving the information sheet and having the chance to ask questions) for a visit of 30-45 minutes. Visits will be arranged in advance at a convenient time.

When participants attend, after agreeing to take part and signing a consent form, participants will take a seat in a private room. Participants will need to wear short sleeves, or roll their sleeves up. If necessary, the investigator can provide a gown to wear if the sleeves are too tight. The investigator will then do the following;

  1. Record some details about medical history, height/weight, whether they take medications, date of birth, whether male or female.
  2. Measure the blood pressure by briefly inflating a cuff around the upper arm.
  3. Place an array of fibre optics on the surface of the forearm. Some jelly will be placed on the skin first, and the array will be held in place by a strap or tape. This is not painful.
  4. After around 10 minutes of sitting quietly, the investigator will inflate a blood pressure cuff around the arm that the array is placed on. This will temporarily prevent blood entering or leaving the arm. This will feel tight and the arm may go numb. The investigator will keep the cuff inflated for five minutes, but the participant can ask for the cuff to be deflated at any time.
  5. The investigator will then deflate the cuff, allowing blood back into the arm. After around 10 more minutes, the investigator will remove the cuff and array and the participant will be free to leave.

After the first assessment, the investigator will ask participants if they would be willing to attend for a second assessment where we would repeat the above measurements. This is to test how reproducible the measurements are in the same individual.

Study 2) Can DOT predict presence or severity of coronary artery disease on angiography?

This study will measure vascular function in patients awaiting diagnostic coronary angiography (either invasive or by CT), in whom it is not known whether or not coronary artery disease is present. Once the angiographic results are available the investigator will correlate vascular function measured by DOT with presence and severity of coronary artery disease to examine whether or not DOT identified

Potential participants will be approached by poster, or face to face in STH clinics and provided with the information sheet which participants will be asked to read. Participants will be given the opportunity to ask questions by email or telephone at any time afterwards. Participants will be asked to contact us if they are willing to participate.

Participants will be booked with an appointment to attend the Clinical Research Facility at Sheffield Teaching Hospitals (at least 24hrs after receiving the information sheet and having the chance to ask questions) for a visit of approximately 45 minutes. Visits will be arranged in advance at a convenient time.

When participants attend, after agreeing to take part and signing a consent form, particpants will take a seat in a private room. Participants will need to wear short sleeves, or roll their sleeves up. If necessary, the investigator can provide a gown to wear if the sleeves are too tight. the investigator will then do the following;

  1. Record some details about medical history, whether they take medications, date of birth, whether male or female.
  2. Measure the blood pressure by briefly inflating a cuff around the upper arm.
  3. Place an array of fibre optics on the surface of the forearm. Some jelly will be placed on the skin first, and the array will be held in place by a strap or tape. This is not painful.
  4. After around 10 minutes of sitting quietly, the investigator will inflate a blood pressure cuff around the arm that the array is placed on. This will temporarily prevent blood entering or leaving the arm. This will feel tight and the arm may go numb. The investigator will keep the cuff inflated for five minutes, but the participant can ask for the cuff to be deflated at any time.
  5. The investigator will then deflate the cuff, allowing blood back into the arm. After around 10 more minutes, the investigator will remove the cuff and array and the participant will be free to leave.

Once the angiogram is performed (as part of their routine clinical care) the results will be reviewed by a clinically trained researcher. This will then be correlated with their vascular function measured by DOT to determine whether this can predict angiographic findings.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
19

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

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 Kingdom
    • South Yorkshire
      • Sheffield, South Yorkshire, United Kingdom, S5 7AU
        • Northern General Hospital

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

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

18 years to 80 years (Adult, Older Adult)

Accepts Healthy Volunteers

Yes

Genders Eligible for Study

All

Description

Inclusion Criteria:

  1. Age 18-80 of either sex
  2. Ability to read and speak English to a level allowing understanding of the patient information and to give consent to participate
  3. Diagnosed as type 2 diabetic for at least 12 months
  4. No painful arms or health problems preventing blood pressure cuff inflation
  5. No lymphoedema of the arm
  6. Not diabetic or known to have suffered a myocardial infarction in the past

Exclusion Criteria:

Any patients that do not meet the above criteria will be excluded

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

  • Primary Purpose: Basic Science
  • Allocation: Non-Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: Vascular function
Diffuse optical tomography detection of differences in vascular function between healthy volunteers and patients with proven heart disease or diabetes.
Device: diffuse optical tomography
Optical tomography is a form of computed tomography that creates a digital volumetric model of an object by reconstructing images made from light transmitted and scattered through an object.
Experimental: Coronary artery disease
Diffuse optical tomography prediction of presence or severity of coronary artery disease on angiography.
Device: diffuse optical tomography
Optical tomography is a form of computed tomography that creates a digital volumetric model of an object by reconstructing images made from light transmitted and scattered through an object.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Can diffuse optical tomography detect microvascular function?
Time Frame: 3 years from start date
Measuring microvascular function with diffuse optical tomography
3 years from start date

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Detecting differences in microvascular function in atherosclerosis
Time Frame: 3 years from start date
Detecting differences in microvascular function using diffuse optical tomography between healthy people and those with atherosclerosis
3 years from start date
Detecting differences in microvascular function in diabetes
Time Frame: 3 years from start date
Detecting differences in microvascular function using diffuse optical tomography between healthy people and those with diabetes
3 years from start date
Predicting coronary artery disease before angiography
Time Frame: 3 years from start date
Predicting coronary artery disease before angiography using diffuse optical tomography
3 years from start date

Collaborators and Investigators

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

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Sheffield Teaching Hospitals NHS Foundation Trust

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
University of Sheffield

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Timothy Chico, University of Sheffield

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.

General Publications

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)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
January 11, 2016

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
March 26, 2020

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
March 26, 2020

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
December 18, 2017

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
January 18, 2018

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
January 26, 2018

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
May 17, 2022

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
May 10, 2022

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
May 1, 2022

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • STH18094

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.

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