ISMRM 24th Annual Meeting & Exhibition 07-13 May 2016 Singapore

Combined Educational & Scientific Session: Tissue Characterization: Brain, Heart & Body

Skill Level: Intermediate to Advanced

Organizer: Garry E. Gold, M.D. & Nicole E. Seiberlich, Ph.D.

Thursday 12 May 2016

This combined educational and scientific course will examine techniques for looking at tissue characterization in the brain, heart, and body.

Target Audience
Physicists interested in understanding the promise and constraints of new techniques for tissue characterization, as well as physicians who want to understand the basic physical principles and potential applications.

Educational Objectives
Upon completion of this course, participants should be able to:

  • To describe and use emerging technologies for characterizing tissue using MRI;
  • To understand similarities and differences between tissue characterization in different parts of the body; and
  • To articulate challenges facing tissue characterization in a clinical setting.

Moderator: Tetsuya Yondeda
Tissue Characterization: Brain
Sean Deoni
MRI offers of wealth of information that indirectly informs ontissue microstructure and organization.  Imaging methods, including qualitative T1, T2 and proton density weighted imaging provide a foundation for assessing gross brain morphology and cortical morphometry.   Beyond this, quantitative methods, including diffusion tensor, magnetisation transfer, and relaxometry can be used to assess more specific attributes of tissue microstructure and architecture.  In this presentation, we will briefly overview these methods, with emphasis on relaxometry analysis to interrogate brain microstructure

Tissue Characterisation: Heart
Reza Nezafat1
Extra-Hepatic Steatosis: New Opportunities and Challenges in Quantitative MR
Takeshi Yokoo1
1UT Southwestern Medical Center
Abnormal lipid metabolism is associated with obesity, resulting in accumulation of fat in non-adipose tissues a process called steatosis. Steatosis has long been known to occur in the liver and skeletal muscle, but also occurs in other organs including the pancreas, heart, and the kidneys, with potential significant pathophysiological implications. In this educational session, we will discuss the clinical significance of extra-hepatic steatosis and the value of quantitative MR in its noninvasive evaluation, as well as future research opportunities and technical challenges.

Structural and hemodynamical contributions to brain T2* relaxation in schizophrenia, bipolar disorder and siblings
Jie Wen1, Daniel Mamah2, Jie Luo3, Xialing Ulrich1, Deanna Barch4, and Dmitriy Yablonskiy1
1Radiology, Washington University, Saint Louis, MO, United States, 2Psychiatry, Washington University, Saint Louis, MO, United States, 3Research Lab of Electronics, MIT, Cambridge, MA, United States, 4Psychology, Washington University, Saint Louis, MO, United States
Investigating brain structure and functioning by means of tissue-specific T2* relaxation properties in vivo can potentially guide the uncovering of neuropathology in psychiatric illness. In this abstract, R2* (=1/T2*) relaxation rate constant was separated into tissue-specific (R2*t) and hemodynamic BOLD contributions. 17 control, 17 bipolar disorder, 16 schizophrenia, and 12 unaffected schizophrenia sibling participants were scanned. A MANOVA of 38 gray matter regions showed significant group effects for BOLD but not for R2*t. Our results suggest that increased baseline activity in certain brain regions is part of the underlying pathophysiology of specific psychiatric disorders.

Radial MOLLI sequence for fast, precise and accurate myocardium T1 mapping
Benjamin Marty1,2, Bertrand Coppa1,2, and Pierre G Carlier1,2
1NMR laboratory, Institute of Myology, Paris, France, 2NMR laboratory, CEA, I2BM, MIRCen, Paris, France
Quantitative cardiac NMR imaging, and more particularly T1 mapping has become a popular modality to characterize myocardial tissue. In this work, we developed and validated a radial variant of the MOLLI acquisition (raMOLLI) that allows to significantly decrease the acquisition time down to 5 heart beats, while keeping high precision on T1 estimation due to a large number of acquired data-points along the T1 relaxation recovery curve. Insensitivity of measured T1 values to heart rate was also demonstrated with this sequence.

Cardiac Magnetic Resonance Reveals Signs of Subclinical Myocardial Inflammation in Asymptomatic HIV-infected Patients
Julian Alexander Luetkens1, Jonas Doerner1, Carolynne Schwarze-Zander2, Jan- Christian Wasmuth2, Christoph Boesecke2, Alois M Sprinkart1, Frederic C Schmeel1, Rami Homsi1, Juergen Gieseke3, Hans H Schild1, and Claas P Naehle1
1Radiology, University of Bonn, Bonn, Germany, 2Internal Medicine I, University of Bonn, Bonn, Germany, 3Philips Research, Hamburg, Germany
People living with chronic human immunodeficiency virus (HIV) infection are at an increased risk for cardiovascular disease. In the present study we investigated HIV-infected patients, which were controlled for the disease, using multiparametric cardiovascular magnetic resonance (CMR). With this CMR approach we could demonstrate that HIV-infected patients without cardiac symptoms not only have subtle evidence of impaired myocardial function, but also elevated markers of myocardial inflammation and increased myocardial fibrosis. These findings indicate subclinical myocardial inflammation in HIV-infected patients despite effective antiretroviral therapy, and therefore may contribute to the persistently increased cardiovascular morbidity and mortality observed in these patients.

MR Imaging of Liver Microstructure in Hepatic Fibrosis and Cirrhosis at 11.7 T - Permission Withheld
Mark Valasek1, Qun He2,3, Claude Sirlin2, Graeme M. Bydder2, and Nikolaus M. Szeverenyi2
1Pathology, University of California, San Diego, San Diego, CA, United States, 2Radiology, University of California, San Diego, San Diego, CA, United States, 3Ningbo Jansen NMR Technology Co., Ltd., Cixi, Zhejiang, China, People's Republic of
We performed MR microscopy at 11.7 T to examine the tissue structure of normal, fibrotic and cirrhotic liver samples.  Images having 100-1,000 times the spatial resolution of clinical MR images were obtained in small tissue samples using an animal imaging system with appropriately small custom T/R solenoid coils.  Diffusion imaging with three direction of sensitization revealed sheet like fibrous structures, exhibiting high signal intensity in regions where the sensitization direction was orthogonal to a sheet.

An Automatic Machine learning Approach for multi-parametric MR based Brown adipose tissue characterization and Segmentation in mice and rats
Bhanu Prakash KN1, Hussein Srour 1,2, Sanjay Kumar Verma1, Jadegoud Yaligar1, Venkatesh Gopalan1, Swee Shean Lee1, Kai Hsiang Chuang 1,2, and Sendhil Velan S1,3
1Laboratory of Metabolic Imaging, Singapore Bioimaging Consortium, Singapore, Singapore, 2Queensland Brain Institute, Brisbane, Australia, 3MRS & Metabolic Imaging Group, Singapore Institute for Clinical Sciences, Singapore, Singapore

We have utilized  multiparametric MR images (fat-fraction (FF), T2 and T2*) of adipose tissues and evaluated different segmentation algorithms like  multidimensional thresholding, region growing, clustering, and machine learning approach for its suitability and efficacy to separate WAT from BAT depots.  A machine learning algorithm i.e. Neural Network based segmentation provided increased specificity compared to other algorithms. This methodology can be easily extended for multi-parametric human images and longitudinal studies.  


Adjournment & Meet the Teachers

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