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Sickle Cell DiseaseHDDOT CVRNCT07776444

Cerebrovascular Reactivity Measurements With High-Density Diffuse Optical Tomography

A study testing Carbon Dioxide in people with Sickle Cell Disease and Cerebral Stroke, run by Washington University School of Medicine at 1 site in United States.

Recruiting

Looking for participants now. Contact the study team or a site below to ask about taking part.

Sites and contacts
Official record

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Trial summary

The purpose of the study protocol is to identify imaging biomarkers for brain tissue under high metabolic stress at risk for permanent injury. We will measure oxygen extraction fraction (OEF) and cerebrovascular reactivity (CVR) in participants with and without perturbations in cerebral oxygen delivery over time to… Read more about this study

Who is it for?
Ages 6 to 70 yearsHealthy volunteers can take part
Conditions the study is for
Sickle Cell Disease, Cerebral Stroke
What is being tested?
Carbon Dioxide
Could I receive a placebo?
No, everyone receives an active treatment
How many people
120 participants
Where
1 siteUnited States
Study dates
1 Oct 2025to 30 Sep 2032
Phase
Interventional

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 6 to 70 years
  • All sexes
  • Healthy volunteers accepted
  • Child, Adult, Older adult

Who may be able to join

  • 6-70 Years Old
  • Able to participate in MRI scan without sedation
  • May or may not have HbSS or beta thalassemia null genotypes of sickle cell anemia

Who cannot join

  • Significant craniofacial malformation or technical contraindications to DOT monitoring (for HDDOT imaging)
  • Metal in/on the body that is contraindicated for MRI safety (for MRI imaging)

Trial locations and contacts

1 site in 1 country. Contact the study team or a site near you to ask about taking part.

Kristin Guilliams, MD contact

3144545436

kristinguilliams@wustl.edu

United States1 site, 1 recruiting
  • Washington University in St. Louis

    St Louis, Missouri, 63110

    Kristin Guilliams, MD, 3144546120, kristinguilliams@wustl.edu

    Kristin Guilliams, MD

    Recruiting

Other trials in United States

About this study

The purpose of the study protocol is to identify imaging biomarkers for brain tissue under high metabolic stress at risk for permanent injury. We will measure oxygen extraction fraction (OEF) and cerebrovascular reactivity (CVR) in participants with and without perturbations in cerebral oxygen delivery over time to determine each parameter's role in clinical and radiologic neurologic outcomes. Measuring OEF can be done with specialized MRI sequences. Measuring CVR requires a vasoactive response, such as carbon dioxide. In order to deliver carbon dioxide evenly and as safely as possible, we will use RespirACT, an MRI-compatible device, to prevent over-breathing carbon dioxide and allow rapid steady-state physiology to minimize total scan time. We will also use a high density diffuse optical tomography (HD-DOT) cap to assess the measurement of OEF and CVR. This study will investigate both regional OEF and CVR simultaneously to understand each marker's unique developmental trajectory and contribution to stroke risk in children. This work will expand insights into mechanisms of stroke in children and assess the feasibility of the HD-DOT cap for obtaining these insights by comparing a cohort of optical CVR and a cohort of MRI CVR.

In addition to the MRI and/or HD-DOT cap with RespirAct, participants may also have their vitals measured, complete cognitive testing, and complete a blood draw with a study visit. Participants may be followed for up to three years and may complete both an MRI scan and an HD-DOT scan within 1 week-12 months of each other. Participants may be invited back to repeat MRI and/or HD-DOT scans 1-2 times over the next three years.

Read the detailed description

The purpose of the study protocol is to identify imaging biomarkers for brain tissue under high metabolic stress at risk for permanent injury. We will measure OEF and CVR in participants with and without perturbations in cerebral oxygen delivery over time to determine each parameter's role in clinical and radiologic neurologic outcomes. Measuring OEF can be done with specialized MRI sequences. Measuring CVR requires a vasoactive response, such as carbon dioxide. In order to deliver carbon dioxide evenly and as safely as possible, we will use RespirACT, an MRI-compatible device, to prevent over-breathing carbon dioxide and allow rapid steady-state physiology to minimize total scan time. We will also use an HD-DOT cap to assess the measurement of OEF and CVR.

Being tested
Carbon Dioxide
Keywords
cerebrovascular reactivity, magnetic resonance imaging, High density diffuse optical tomography
Medical subject headings
Anemia, Sickle Cell, Stroke

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • Carbon DioxideOther

    Participants inhale carbon dioxide, delivered by computer-controlled delivery system, to target specific levels of carbon dioxide while in magnetic resonance imaging scan and/or during HDDOT imaging to measure cerebrovascular reactivity.

Study groups in NCT07776444
Study groupRoleWhat they receive
Healthy ControlsActive comparatorNot described
Receives: Other: Carbon Dioxide
Sickle Cell Anemia ParticipantsActive comparatorNot described
Receives: Other: Carbon Dioxide

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. HDDOT-Based Cerebrovascular Reactivity

    Changes in relative concentration of deoxyhemoglobin with fluctuations of carbon dioxide as compared to gold standard measurement of MRI-based cerebrovascular reactivity.

    Measured: ~15 minutes during the MRI scan and ~60 minutes during the HDDOT imaging.

Secondary outcomes (1)
  1. Cerebral Oxygen Metabolism

    MRI-based cerebral based blood flow oxygen extraction fraction will be combined with laboratory data estimating arterial oxygen content to calculate cerebral oxygen metabolism.

    Measured: From administration of carbon dioxide to end of inhalation of carbon dioxide -- 60 minutes during MRI and/or HDDOT imaging.

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted20 Aug 2026
  2. Study start1 Oct 2025
  3. Primary completion30 Sep 2030 (estimated)
  4. Study completion30 Sep 2032 (estimated)

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase N/A
Primary purpose
Basic science
Allocation
Non-randomised
Intervention model
Single group
Model description
All arms will receive the same study conditions.
Masking
None (open label)
Enrolment
120 participants (estimated)
IDs, dates and publications
ClinicalTrials.gov ID
NCT07776444
Sponsor's protocol ID
202508036
Acronym
HDDOT CVR
Status last verified
Aug 2026
First submitted
22 Sep 2025
Last updated
20 Aug 2026
Results posted
No
Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No

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