AUTHOR=Huelnhagen Till , Paul Katharina , Ku Min-Chi , Serradas Duarte Teresa , Niendorf Thoralf 

TITLE=Myocardial T2* Mapping with Ultrahigh Field Magnetic Resonance: Physics and Frontier Applications

JOURNAL=Frontiers in Physics

VOLUME=5

YEAR=2017

URL=https://www.frontiersin.org/journals/physics/articles/10.3389/fphy.2017.00022

DOI=10.3389/fphy.2017.00022

ISSN=2296-424X

ABSTRACT=<p>Cardiovascular magnetic resonance imaging (CMR) has become an indispensable clinical tool for the assessment of morphology, function and structure of the heart muscle. By exploiting quantification of the effective transverse relaxation time (<inline-formula><mml:math id="M2" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msup><mml:mrow><mml:msub><mml:mi>T</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:mrow><mml:mo>*</mml:mo></mml:msup></mml:mrow></mml:math></inline-formula>) CMR also affords myocardial tissue characterization and probing of cardiac physiology, both being in the focus of ongoing research. These developments are fueled by the move to ultrahigh magnetic field strengths, which permits enhanced sensitivity and spatial resolution that help to overcome limitations of current clinical MR systems with the goal to contribute to a better understanding of myocardial (patho)physiology <italic>in vivo</italic>. In this context, the aim of this report is to introduce myocardial <inline-formula><mml:math id="M3" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msup><mml:mrow><mml:msub><mml:mi>T</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:mrow><mml:mo>*</mml:mo></mml:msup></mml:mrow></mml:math></inline-formula> mapping at ultrahigh magnetic fields as a promising technique to non-invasively assess myocardial (patho)physiology. For this purpose the basic principles of <inline-formula><mml:math id="M4" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msup><mml:mrow><mml:msub><mml:mi>T</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:mrow><mml:mo>*</mml:mo></mml:msup></mml:mrow></mml:math></inline-formula> assessment, the biophysical mechanisms determining <inline-formula><mml:math id="M5" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msup><mml:mrow><mml:msub><mml:mi>T</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:mrow><mml:mo>*</mml:mo></mml:msup></mml:mrow></mml:math></inline-formula> and (pre)clinical applications of myocardial <inline-formula><mml:math id="M6" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msup><mml:mrow><mml:msub><mml:mi>T</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:mrow><mml:mo>*</mml:mo></mml:msup></mml:mrow></mml:math></inline-formula> mapping are presented. Technological challenges and solutions for <inline-formula><mml:math id="M7" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msup><mml:mrow><mml:msub><mml:mi>T</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:mrow><mml:mo>*</mml:mo></mml:msup></mml:mrow></mml:math></inline-formula> sensitized CMR at ultrahigh magnetic field strengths are discussed followed by a review of acquisition techniques and post-processing approaches. Preliminary results derived from myocardial <inline-formula><mml:math id="M8" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msup><mml:mrow><mml:msub><mml:mi>T</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:mrow><mml:mo>*</mml:mo></mml:msup></mml:mrow></mml:math></inline-formula> mapping in healthy subjects and cardiac patients at 7.0 T are presented. A concluding section discusses remaining questions and challenges and provides an outlook on future developments and potential clinical applications.</p>