Measuring Cerebral Blood Flow Using Pseudo-continuous Arterial Spin Labeling Perfusion Magnetic Resonance Imaging

Study Overview
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Brief Summary
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This study will test a new MRI sequence that measures cerebral blood flow (CBF). Because this technique for measuring CBF is new, there is little information on what the normal values for different regions of the brain should be. Information from the study will be used to establish normative CBF values for the brain, improving the reliable use of this technique for the diagnosis of brain injury or disease.

Detailed Description
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Cerebral blood flow (CBF) represents an important physiological parameter for the diagnosis and management of multiple brain disorders. The clinical need for CBF measurements is further complicated by the desire to have a non-invasive method with high temporal resolution that can measure CBF over a wide range of blood flows and in a wide range of patients. Numerous techniques are available to measure CBF. Nuclear medicine approaches, such as single positron emission computed tomography (SPECT) and positron emission tomography (PET) rely on radioisotopes which can be problematic in the pediatric population. In contrast, MRI-based methods are non-invasive and the CBF information can be obtained in conjunction with other MRI techniques (i.e. diffusion weighted imaging or spectroscopy) which allows for a combined longitudinal assessment of CBF, morphology, and metabolism, to provide a more complete understanding of the developing pathophysiological mechanisms. Arterial spin labeling (ASL) perfusion imaging uses arterial blood water as an endogenous diffusible tracer where radiofrequency (RF) pulses magnetically label the moving spins in flowing blood without the use of a contrast agent. After a time delay allowing for the magnetically labeled blow to flow into the brain, labeled images are acquired. Separate control images are also acquired, without labeling and the difference between the two sets of imaged provides a measure of perfusion. Since gadolinium-based contrast agents are not required, the ASL perfusion technique is completely non-invasive. In addition, ASL techniques are insensitive to blood-brain barrier permeability changes, which can occur after strokes or with tumors. Because gadolinium-based contrast is not used, the ASL technique has an inherently lower sensitivity than DSC-PWI. To date, there are a number of commercially available ASL techniques that differ in their labeling schemes, which has contributed to the difficulty in obtaining consistent results across different patient populations (pediatric, elderly, stroke, tumors). A number of recent reports using pseudo-continuous ASL (pCASL) have been published and show increased reliability across different patient populations. Moreover, a recent consensus statement published by the International Society of Magnetic Resonance in Medicine Perfusion Study Group recommends the use of pCASL labeling strategies for clinical applications. The objectives of this study is to determine the accuracy and reliability of a newly developed pCASL sequence and post-processing software across multiple patient populations (neonate to elderly) and pathological processes.

Official Title
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Measuring Cerebral Blood Flow Using Pseudo-continuous Arterial Spin Labeling Perfusion Magnetic Resonance Imaging

Conditions
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Traumatic Brain Injury, Multiple Sclerosis, Alzheimer's Disease, Tumor

Intervention / Treatment
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* Device: Magnetic Resonance Imaging


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Any person between the ages of 18-90 years, who is undergoing routine magnetic resonance imaging (MRI) of the head with or without contrast at Loma Linda University Medical Center. Must be eligible for MRI (no electronic or metal implants that are not MR compatible). Exclusion Criteria: Electronic or metal implant that is not MRI safe, pregnancy or claustrophobia.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Magentic Resonance Imaging<br>magnetic Resonance Imaging. | Device: Magnetic Resonance Imaging<br>* All participants will have be given a MRI using a pseudo-continuous arterial spin labeling perfusion sequence.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Regional Cerebral Blood Flow Values of the Brain Measured Using Pseudo-continuous Arterial Spin Labeling (pCASL) MRI. | The relative cerebral blood flow (CBF) in frontal, parietal, occipital gray matter and white matter regions, basal ganglia, thalami, and cerebellum will be measured using region of interest analysis to determine institutional normative values for healthy subjects. | single encounter |