Single and multi-frequency saturation methods for molecular and microstructural contrast in human MRI”

Date:
20
Thursday
June
2019
Lecture / Seminar
Time: 10:00-11:00
Location: Perlman Chemical Sciences Building
Lecturer: Prof. Elena Vinogradov
Organizer: Department of Molecular Chemistry and Materials Science
Contact: ana.naamat@weizmann.ac.il
Details: UT Southwestern Medical Center
Abstract: Magnetic Resonance Imaging (MRI) provides excellent quality images of soft tissu ... Read more Magnetic Resonance Imaging (MRI) provides excellent quality images of soft tissues and is an established modality for diagnosis, prognosis and monitoring of various diseases. Majority of MRI scans in clinical practice today report on anatomy, morphology and sometimes physiology. The new area of active studies is aimed at developing MRI contrast methods for the detection of the events at the microstructural and molecular level employing endogenous properties. Here, we will discuss methods that employ single- and multi-frequency saturation to detect events on microstructural and molecular level. First, we will describe principles and translational aspects of Chemical Exchange Saturation Transfer1(CEST). CEST employs selective saturation of the exchanging protons and subsequent detection of the water signal decrease to create images that are weighted by the presence of a metabolite or pH2. We will describe aspects of translating CEST to reliable clinical applications and discuss its potential uses in human oncology, specifically breast cancer. Second, we will describe a method called inhomogeneous Magnetization Transfer3 (ihMT), which employs dual-frequency saturation to create contrast originating from the residual dipolar couplings and thus specific to microstructure. We will focus on the application of ihMT to the detection of myelin in brain and spinal cord. Finally, we will discuss a novel exchange-sensitive method based on the balanced steady-state free precession (bSSFP) sequence as an alternative way for chemical exchange detection (bSSFPX4). Using an effective field description, similarities between bSSFP and CW application can be explored and utilized for in-vivo MRI contrast. [1] K. Ward, et.al., JMR,143,79-87 (2000). [2] J. Zhou, et.al., Nature Medicine, 9,1085-1090 (2003). [3] G. Varma, et.al., MRM, 73, 614-622 (2015). [4] S. Zhang, et.al., JMR, 275, 55-67 (2017).
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