NCT04537611

Brief Summary

To investigate a new method to rapidly modulate pulmonary venous hemoglobin oxygen saturation to enable the use of deoxyhemoglobin concentration in arterial blood as an intra-arterial MRI contrast agent for cerebral tissue perfusion imaging.

Trial Health

43
At Risk

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Trial has exceeded expected completion date
Enrollment
25

participants targeted

Target at below P25 for not_applicable

Timeline
Completed

Started Aug 2021

Shorter than P25 for not_applicable

Geographic Reach
1 country

1 active site

Status
unknown

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

June 2, 2020

Completed
3 months until next milestone

First Posted

Study publicly available on registry

September 3, 2020

Completed
11 months until next milestone

Study Start

First participant enrolled

August 1, 2021

Completed
1 month until next milestone

Primary Completion

Last participant's last visit for primary outcome

September 1, 2021

Completed
6 months until next milestone

Study Completion

Last participant's last visit for all outcomes

March 1, 2022

Completed
Last Updated

April 27, 2021

Status Verified

April 1, 2021

Enrollment Period

1 month

First QC Date

June 2, 2020

Last Update Submit

April 26, 2021

Conditions

Stenosis, CarotidStrokeNeurovascular Disorder

Outcome Measures

Primary Outcomes (1)

  • dHb contrast investigation via MR imaging

    We will measure cerebral blood flow using our hypoxic stimulus combined with functional MRI-Blood oxygen level dependent (BOLD) of the brain and compare it to cerebral blood flow measurements obtained from routine clinical gadolinium contrast imaging.

    1 year

Study Arms (1)

dHb contrast compared to gadolinium contrast imaging

EXPERIMENTAL

Subjects will be referred for a clinical gadolinium contrast perfusion exam. Gas manipulation will be supplied by a programmable computer-controlled gas delivery system while subjects are in the MRI scanner. In addition to their prescribed clinical scans, two additional scans will be obtained: 1) a structural sequence (, followed by 2) a BOLD-EPI sequence while inducing changes of PO2. PO2 will be held at a baseline of 45-50 mmHg for 60s. For 10 s, the lung PO2 will be transiently raised to peak PO2 of 90-120 mmHg (normoxia) within 2 s transition, and then returned to baseline. Alternatively, the baseline may be at normoxia and the gas challenges will target PO2 of 45-50 mmHg. A total of 4 such ventilatory challenges will be applied over 6 min while maintaining normocapnia.

Diagnostic Test: dHb contrast and gadolinium contrast imaging

Interventions

dHb contrast and gadolinium contrast imagingDIAGNOSTIC_TEST

see arm description

dHb contrast compared to gadolinium contrast imaging

Eligibility Criteria

Age18 Years - 80 Years
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Clinical suspicion of a disorder that affects the control of brain blood flow.
  • Previous investigations that indicate the presence of a vascular disorder including history, physical examination, laboratory testing, and imaging.

You may not qualify if:

  • Unwilling or unable to co-operate with breathing manoeuvers
  • Respiratory or cardiac limitations to breathing at 20 L/min
  • Exercise limitation on history of inability to climb one flight of stairs or walk a city block due to shortness of breath
  • Medical contra-indications to limited hypercapnia or hypocapnia (known increased intracerebral pressure, metabolic acidosis or alkalosis)
  • Standard contraindications for MRI scanning (see consent form)
  • Non compliance with prescribed anti-seizure medication
  • Ingestion of caffeine, or smoking within 6 hours of the test
  • Pregnancy
  • Baseline SaO2 \< 95%,
  • Propensity of right to left shunt: lung AVM, patent foramen ovale, atrial-septal defect, ventricular septal defect.
  • History of congestive heart failure, myocardial infarction
  • known coronary artery disease, congenital heart lesion, valvular heart lesion other than mild mitral regurgitation, cardiomyopathy with ejection fraction \< 50%

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Joseph Fisher

Toronto, Ontario, M5G 2C4, Canada

Location

MeSH Terms

Conditions

Carotid StenosisStroke

Condition Hierarchy (Ancestors)

Carotid Artery DiseasesCerebrovascular DisordersBrain DiseasesCentral Nervous System DiseasesNervous System DiseasesArterial Occlusive DiseasesVascular DiseasesCardiovascular Diseases

Study Officials

  • David Mikulis

    Univeristy Health Network

    PRINCIPAL INVESTIGATOR

Central Study Contacts

Joseph Fisher

CONTACT

416-710-6908joe.fisher@utoronto.ca

Olivia Sobczyk

CONTACT

647-289-0266olivia.sobczyk@uhn.ca

Study Design

Study Type
interventional
Phase
not applicable
Allocation
NA
Masking
NONE
Purpose
DIAGNOSTIC
Intervention Model
SINGLE GROUP
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Anesthesiologist

Study Record Dates

First Submitted

June 2, 2020

First Posted

September 3, 2020

Study Start

August 1, 2021

Primary Completion

September 1, 2021

Study Completion

March 1, 2022

Last Updated

April 27, 2021

Record last verified: 2021-04

Data Sharing

IPD Sharing
Will not share

Locations

CA(1)