A Study on Hemodynamic Relationship Including Cerebral Blood Flow Using Phase Contrast and Signal Intensity Gradient of Brain Magnetic Resonance Imaging, and Carotid Doppler Ultrasound

Study Overview
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Brief Summary
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Cerebral blood flow measurement, which is applied to patients with cerebrovascular-related diseases, provides useful information about hemodynamic status. There was a method using Doppler ultrasound and phase contrast (PC) MRI, but it was not widely used in clinical practice due to limitations in reproducibility between examiners, complexity of procedure, and time-intensive protocol. We intend to measure cerebral blood flow through the signal-intensity gradient (SIG) technique using Time-of-Flight (TOF) of brain magnetic resonance imaging, which can compensate for the shortcomings of the existing research methods. In addition, by analyzing the correlation with the previous methods, Doppler ultrasound and PC MRI, we will evaluate the effectiveness of our new method.

Official Title
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A Study on Hemodynamic Relationship Including Cerebral Blood Flow Using Phase Contrast and Signal Intensity Gradient of Brain Magnetic Resonance Imaging, and Carotid Doppler Ultrasound

Conditions
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Cerebral Blood Flow

Intervention / Treatment
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* Diagnostic Test: Signal intensity gradient


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients 18 years of age or older who have been admitted to the neurology department due to a stroke, and those who have already performed brain magnetic resonance imaging Among the patients (1) who underwent carotid artery Doppler ultrasound Patients who fully understand the research objectives and procedures and wish to participate in clinical research voluntarily If a patient is not fully understood due to a decrease in awareness or consciousness, the consent of the legal representative is required Exclusion Criteria: Patients whose extracranial artery occlusion or severe stenosis was confirmed in brain magnetic resonance images. Those who judge that the subject is unsuitable for participation in clinical research due to other reasons.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Subjects<br>Cerebral blood flow of a subject is measured using three methods in both common carotid and vertebral arteries. 1) Phase-contrast MR 2) Doppler sonography 3) Signal Intensity Gradient (SIG) To determine whether there is a correlation between the measured values, the correlation coefficient is calculated and analyzed. | Diagnostic Test: Signal intensity gradient<br>* Signal intensity gradient: In time-of-flight (TOF) MRA, The signal intensities at the iso-point (Φa; signal intensity at position A [Xa] along the arterial contour line) and at the inner point (Φb; signal intensity at position B [Xb]) were calculated by using a trilinear interpolation algorithm based on the positions and signal intensities in the eight neighboring voxels. The signal intensities of TOF-MRA were normalized to eliminate the offset and scale effects across the MRA datasets of participants. For each iso-point (position A), the SIG was calculated from the difference in signal intensities between points A and B as follows: Scalar SIG, SI/mm = (Φb - Φa) / │Xb - Xa│ (1) Vector SIG, SI/mm = (Φb - Φa) n / │Xb - Xa│ (2)<br>* Other names: Carotid Doppler sonography;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cerebral blood flow correlation | Cerebral blood flow correlation between 3 tests (SIG, PC MR, US) | After completion of recruitment, average 1 year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Endothelial shear stress, signal-intensity gradient, phase contrast MRI, Time-of-Flight MRI, Carotid Doppler sonography