Non-invasive Measurement of Cerebral Dynamic Autoregulation (TOMCAT)

The overall objective of this study is to evaluate the use of diffuse correlation spectroscopy to non-invasively measure dynamic cerebral autoregulation in subjects with vascular risk factors. Optical cerebral blood flow measurements will be correlated with changes in arterial blood pressure to assess how CBF is maintained in response to changes in ABP, and will be compared to transcranial doppler reference measurements.

Study Overview

• Status: Completed
• Conditions: Stroke
• Intervention / Treatment: Device: Thigh Cuff

• Study Type: Interventional
• Enrollment (Actual): 21
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Pennsylvania
    • Philadelphia, Pennsylvania, United States, 19104
      • Hospital of the University of Pennsylvania

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 50 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Age greater than or equal to 50 years
• Positive history of at least one of the following vascular disk factors: hypertension, diabetes, hyperlipidemia, coronary artery disease, atrial fibrillation, prior myocardial infarct, transient ischemic attack, or history of smoking

Exclusion Criteria:

• Vascular risk factor subjects:

  1. Pregnant women
  2. Prisoners
  3. Prior neurosurgical procedure or traumatic brain injury, including hemicraniectomy or other skull defect
  4. Prior history of ischemic or hemorrhagic stroke
  5. Prior lower extremity amputation
  6. Peripheral vascular disease

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Intervention; We will measure dCA with both TCD and DCS during acute changes in mean arterial pressure using thigh cuff deflation techniques in vascular risk factor subjects. Measurements will be compared between TCD and DCS in order to validate DCS as a tool to measure dCA in this population.	Device: Thigh Cuff

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
dCA Measurement During Acute Changes in Mean Arterial Pressure, TCD	Rate of Regulation, measured using transcranial doppler. Rate of regulation (ROR) is calculated as follows: ROR = (change in relative cerebrovascular resistance / change in time) / maximum fractional decrease in blood pressure due to thigh cuff deflation.	1.5 hours
dCA Measurement During Acute Changes in Mean Arterial Pressure, Optical	Rate of Regulation, measured using diffuse correlation spectroscopy. Rate of regulation (ROR) is calculated as follows: ROR = (change in relative cerebrovascular resistance / change in time) / maximum fractional decrease in blood pressure due to thigh cuff deflation.	1.5 hours

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Linear Relationship Between Rate of Regulation Measured Using TCD and Optics	Linear relationship between Rate of Regulation measured using TCD and Optics, expressed as slope of linear fit	1.5 hours

Collaborators and Investigators

• Sponsor: University of Pennsylvania

Study record dates

Study Major Dates

• Study Start (Actual): June 1, 2015
• Primary Completion (Actual): March 1, 2019
• Study Completion (Actual): March 1, 2020

Study Registration Dates

• First Submitted: May 8, 2015
• First Submitted That Met QC Criteria: May 12, 2015
• First Posted (Estimate): May 13, 2015

Study Record Updates

• Last Update Posted (Actual): August 14, 2020
• Last Update Submitted That Met QC Criteria: August 3, 2020
• Last Verified: August 1, 2020

More Information

Terms related to this study

• Other Study ID Numbers: 821705