stroke-vascular-dementia-2019-posters-abstracts

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March 14-16, 2019 | London, UK

International Conference on

Vascular Dementia and Dementia

Neurological Disorders and Stroke

Joint Event

Journal of Brain and Neurology | Volume 3

Noninvasive Magnetic Resonance Imaging for Quantitative Brain Assessment

Renata Ferranti Leoni

University of São Paulo, Brazil

agnetic Resonance Imaging (MRI) for the assessment

of cerebral blood perfusion has been routinely used

for an increasing number of clinical indications, including

cerebrovascular diseases, neoplasms, degenerative and

psychiatric disorders. Noninvasive and quantitative MRI

techniques include the Arterial Spin Labeling (ASL) and

Intravoxel Incoherent Motion (IVIM). ASL uses hydrogen

present in arterial blood as an endogenous contrast agent.

Briefly, the method consists of magnetically labeling arterial

blood by applying radiofrequency pulses. After the labeled

blood reaches the region of interest, the images are acquired

and then subtracted from control images (without labeling),

resulting in a perfusion-weighted map proportional to the

cerebral blood flow (CBF). Then, image processing and signal

modeling enable CBF quantification. In addition to CBF maps,

ASL provides information about perfusion territories of main

cerebral arteries, vascular reactivity to hypercapnia challenge,

and functional response of the brain during a task or at rest.

Moreover, IVIM is a diffusion-weighted MRI method, which

can separate the intravoxel signal into classical diffusion and

perfusion-related contributions. Its combination with ASL

enables quantitative assessment of the blood-brain barrier

permeability without using an exogenous contrast agent, as the

gadolinium. Therefore, I will discuss the basic principles, main

applications, methodological difficulties and limitations of both

ASL and IVIM for the assessment of neurological disorders.