ORGANIZERS: Hanzhang Lu, Ph.D. & Stephan E. Maier, M.D.,Ph.D.
Sunday, 23 April 2017
||08:15 - 11:45
||Hanzhang Lu, Stephan Maier
Skill Level: Intermediate
Slack Channel: #e_diff_perf_fmri
Session Number: WE17
This session will introduce IVIM (intravoxel incoherent motion) technique and its applications. This session will also describe approaches to evaluate cerebrovascular reserve and its clinical and basic science utility.
Physicists and clinicians who are interested in novel MR techniques to evaluate perfusion properties without contrast agent.
Upon completion of this course, participants should be able to:
-Describe the basic mechanism of IVIM;
-Identify the proper approaches to acquire and analyze IVIM data for basic science and clinical applications;
-Recognize the strengths and limitations of IVIM technique;
-Explain the physiological underpinnings of cerebrovascular reserve;
-Describe basic approaches to measure and interpret cerebrovascular reserve; and
-Explain typical utility of cerebrovascular reserve.
|Introduction to IVIM
Denis Le Bihan
Intravoxel Incoherent Motion (IVIM) refers to translational movements which within a given voxel and during the measurement time present a distribution of speeds in orientation and/or amplitude. The IVIM concept has been used to estimate perfusion in tissues as blood flow in randomly oriented capillaries mimics a pseudo-diffusion process. IVIM-based perfusion MRI, which does not require contrast agents, has gained momentum recently, especially in the field oncology. In this introduction the basic principles, models, technical requirements and limitations inherent to IVIM-based perfusion MRI, as well as new, non-perfusion applications of IVIM MRI, such as virtual MR Elastography will be outlined.
|IVIM in the Body
Intravoxel incoherent motion (IVIM), which decomposes diffusion-weighted MRI signals in to microcirculation and microstructural components, has seen tremendous application throughout the body. This presentation will review the major trends, findings, and challenges of this surge of activity.
|IVIM in the Brain
The lecture targets physicists, engineers and physicians with an interest in advanced brain perfusion imaging with intravoxel incoherent motion.
|Break & Meet the Teachers
|Introduction To Cerebrovascular Reserve & Its Measurements
Jill De Vis
Cerebrovascular reserve is a marker of the brain's ability to compensate for a decreased perfusion pressure which would otherwise lead to a decreased cerebral blood flow with consequently ischemic events. In this lecture we will describe the concept of cerebrovascular reserve, we will briefly go through the different MRI methods to evaluate the cerebrovascular reserve and we will describe the challenges available to assess the cerebrovascular reserve.
|MRI Measurement of Cerebrovascular Reactivity: Clinical Implementation
The interest in translating MRI mapping of cerebrovascular reactivity (CVR) for the clinical assessment of hemodynamic insufficiency secondary to cerebrovascular disease is increasing. This presentation will focus on the current issues and potential solutions facing widespread dissemination of this methodology. Issues regarding the flow stimulus, flow sensitive pulse sequences, data analysis, and clinically relevant detection thresholds will be presented.
|Applications of Cerebrovascular Reserve: Vascular Disease, Tumor, fMRI, Etc.
Measuring the brain perfusion responsive to the external vasodilators, termed cerebrovascular reactivity (CVR), is a useful tool towards better understanding of brain pathophysiological conditions, such as arterial stenosis, brain tumor, dementia, and traumatic brain injury. Moreover, CVR evaluation could serve as a novel approach to normalize the BOLD fMRI signal and quantify neural activity evoked by stimulation in calibrated fMRI as well, paving the way for neuroscience research.