MedPath

Non-Invasive Mapping of Cerebral Autoregulation Using Near Infrared Spectroscopy

Not Applicable
Recruiting
Conditions
Cerebral Autoregulation Mapping
Interventions
Procedure: Transient hyperemic response
Procedure: Orthostatic challenge
Procedure: Vascular chemo-reactivity
Procedure: Neurovascular coupling
Registration Number
NCT05433129
Lead Sponsor
University of Manitoba
Brief Summary

The investigators propose to employ advanced multi-channel near non-invasive near infrared spectroscopy (NIRS) system married with entirely non-invasive continuous arterial blood pressure (niABP) monitor to create a new wearable and portable imaging system that derives CA maps of the entire brain with high sampling rates at each point.

The objectives of this project are as follows:

1. To perform in vivo testing and optimization of the device using a block-trial design to evaluate the CA mapping system's performance during various perturbations.

2. To explore the impact of aging and sex on regional disparities in CA in a healthy volunteer population using static recording along with perturbation testing.

Detailed Description

Objective 1:

To assess functionality and feasibility of real-time application in humans, in vivo testing will occur on a small population (n=50) of healthy human volunteers. Such work will investigate feasibility of the combination monitoring setup, optimal NIRS channel placement using the adjustable OxyMon NIRS cap, ability for pipelines to extract and analyze signals in real time for continuous derivation of NIRS-based CVR metrics at each channel and functionality of CVR map generation in real-time. Finally, the investigators will investigate perturbations to system through a series of testing (block design separated by baseline rest): A. transient hyperemic response testing via carotid compression methods, B. orthostatic challenge responses (lying-to-sit, sit-to-stand), C. vascular chemo-reactivity via fast and slow breathing exercises and D. impact of neurovascular coupling through cognitive/Stroop testing. Work here will establish areas for improvement in real time. The testing and optimization phase will last 18 months. The addition of single rSO2 channel from commercial NIRS will be used to provide a "gold standard" data stream to compare our results to.

Objective 2:

Current understanding of the aging process and sex on continuously assessed CA, and regional disparities, has been hampered by a lack of high-resolution platform. The investigators will evaluate the impact of both age and sex on CA using the newly developed platform through static CA assessments in 200 healthy volunteers. Within the 1-hour period, volunteers will have their age and sex recorded in a de-identified electronic database, have an hour of non-invasive simultaneous 24 Channel OxyMon NIRS , Finapres NOVA ABP, and single channel commercial NIRS rSO2 recording which is divided into static resting state recording and perturbation testing. This will facilitate the derivation of a normative reference range for CA using the platform along with making the dataset richer. Static resting state assessments will be done over the first half hour and in second half hour, perturbations to system will be investigated through a series of testing separated by baseline rest: A. orthostatic challenge responses (lying-to-sit, sit-to-stand), B. vascular chemo-reactivity via fast and slow breathing exercises and C. impact of neurovascular coupling through Stroop testing. The addition of single rSO2 channel from commercial NIRS will be used to provide a "gold standard" data stream to compare our results to.

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
250
Inclusion Criteria
  • Healthy volunteers (male and female)
  • Age > 17
Exclusion Criteria
  • History of neurological illness
  • History of systemic vascular
  • History of cerebrovascular disease

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Arm && Interventions
GroupInterventionDescription
Block TestingTransient hyperemic responsePerturbations to the system will be investigated through a series of testing (block design separated by baseline rest): A. transient hyperemic response testing via carotid compression methods, B. orthostatic challenge responses (lying-to-sit, sit-to-stand),8 C. vascular chemo-reactivity via fast and slow breathing exercises and D. impact of neurovascular coupling through cognitive/Stroop testing. Work here will establish areas for improvement in real time.
Block TestingOrthostatic challengePerturbations to the system will be investigated through a series of testing (block design separated by baseline rest): A. transient hyperemic response testing via carotid compression methods, B. orthostatic challenge responses (lying-to-sit, sit-to-stand),8 C. vascular chemo-reactivity via fast and slow breathing exercises and D. impact of neurovascular coupling through cognitive/Stroop testing. Work here will establish areas for improvement in real time.
Block TestingVascular chemo-reactivityPerturbations to the system will be investigated through a series of testing (block design separated by baseline rest): A. transient hyperemic response testing via carotid compression methods, B. orthostatic challenge responses (lying-to-sit, sit-to-stand),8 C. vascular chemo-reactivity via fast and slow breathing exercises and D. impact of neurovascular coupling through cognitive/Stroop testing. Work here will establish areas for improvement in real time.
Block TestingNeurovascular couplingPerturbations to the system will be investigated through a series of testing (block design separated by baseline rest): A. transient hyperemic response testing via carotid compression methods, B. orthostatic challenge responses (lying-to-sit, sit-to-stand),8 C. vascular chemo-reactivity via fast and slow breathing exercises and D. impact of neurovascular coupling through cognitive/Stroop testing. Work here will establish areas for improvement in real time.
Primary Outcome Measures
NameTimeMethod
In Vivo testing and optimization of device during various perturbations2 years

To assess functionality and feasibility of real-time application in humans, in vivo testing will occur on a small population of healthy human volunteers. Such work will investigate feasibility of the combination monitoring setup, optimal NIRS channel placement using the adjustable OxyMon NIRS cap, ability for pipelines to extract, and analyze signals in real time for continuous derivation of NIRS-based CVR metrics at each channel and functionality of CVR map generation in real-time.

Explore impact of aging and sex on regional disparities in Cerebral Autoregulation3 years

Current understanding of the aging process and sex on continuously assessed CA, and regional disparities, has been hampered by a lack of high-resolution platform. We will evaluate the impact of both age, and sex on CA using the newly developed platform through static CA assessments in healthy volunteers.

Secondary Outcome Measures
NameTimeMethod

Trial Locations

Locations (1)

Health Sciences Centre (HSC)

🇨🇦

Winnipeg, Manitoba, Canada

© Copyright 2025. All Rights Reserved by MedPath