From ultrahigh to extreme field magnetic resonance: where physics, biology and medicine meet

Abstract

UHF-MR can see a clear route forward for resolving technological issues and can outline some of the new opportunities that will accompany even higher field strengths. The issue provides an overview of the state of the art and discusses the clinical relevance of what we have already observed and can clearly foresee. Articles are devoted to development of novel methodology [12][13][14][15][16], safety topics [17][18][19] early multicenter trials [20], frontier human studies [21][22][23][24][25][26][27][28], breakthrough clinical applications [29][30][31][32][33][34][35][36] and future directions of UHF-MR [37,38]. At the moment some of these new concepts and clinical applications are merely of proof-of-principle nature and visions, but they are compelling enough to drive the field forward. We hope to engage the interest of clinicians, basic scientists, engineers, translational researchers and applied scientists from many areas, and particularly to attract young scientists and new entrants into the field. In doing so, we hope to convince the MR imaging and spectroscopy communities to throw their weight into the task of solving technical problems and conceiving new clinical applications. UHF MR has a staggering number of potential uses in neuroscience, neurology, radiology, cardiology, internal medicine, oncology, nephrology, ophthalmology and other related clinical fields. As they are developed, we will push the boundaries of MR physics, biomedical engineering and biomedical sciences in many other ways.Another reason this special issue is timely is because physicists, engineers and pioneers from related disciplines have already taken an even further step into the future, in their minds, with something they are calling Extreme Field MR (EF-MR). This envisions human MR at 20 T [37,38], and it is an important leap of the imagination because it aims to fill a crucial "resolution gap" in our understanding of human biology [39,40]. While discoveries are pouring in on the molecular and cellular level every day, it is The development of ultrahigh-field magnetic resonance (UHF-MR) is moving forward at an amazing speed that is breaking through technical barriers almost as fast as they appear. UHF-MR has become an engine for innovation in experimental and clinical research [1][2][3][4][5][6][7][8][9][10][11]. With more than 35,000 MR examinations already performed at 7.0 Tesla, the reasons for moving UHF-MR into clinical applications are more compelling than ever. The value of high-field MR has already proven itself many times over at lower field strengths; now 7.0 T has opened a window on tissues, organs and (patho)physiological processes that have been largely inaccessible in the past. Images from these instruments have revealed new aspects of the anatomy, functions and physio-metabolic characteristics of the brain, heart, joints, kidneys, liver, eye and other organs/tissues, at an unparalleled quality. The number 35,000 sounds large, but in fact we have barely cracked open the door and have yet to truly assess what lies on...

Ultrahigh field MRI determination of water diffusion rates in ex vivo human lenses of different age

“…Improvements in image resolution together with the introduction of enhanced DWI-MRI mapping techniques in ophthalmic examinations was demonstrated by Paul et al using magnetic field strengths of 3.0 T, 7.0 T, and 9.4 T (31,32). Ultrahigh field (UHF-MRI), and extreme field MRI (EF-MRI) at 20 Tesla and beyond were recommended to boost spatial resolution and close the wide gap between the view of biologists and clinicians (33).…”

NMR of Macromolecular Assemblies and Machines at 1 GHz and Beyond: New Transformative Opportunities for Molecular Structural Biology

“…(For reviews of applications of high magnetic fields to MRI see references (8, 9). ) Here we focus on advancements in technology and methodology as applied in the burgeoning field of NMR at field strengths above 1 GHz.…”

B1 inhomogeneity correction of RARE MRI with transceive surface radiofrequency probes

“…The ability of MRI to provide high spatial resolution images within short acquisition times is governed by the sensitivity conundrum, which balances the constraints of signal-to-noise (SNR), image contrast, spatial resolution, and temporal resolution. [1][2][3][4][5] Numerous approaches have been developed to improve SNR per scan time from the development of novel softwaredriven approaches (eg, parallel imaging, 6,7 compressed sensing 8 ), to hardware improvements, including higher magnetic field strengths (B 0 ) [9][10][11] and the optimization of radiofrequency (RF) technology. The use of surface RF coils is common practice to boost sensitivity 12 in (pre)clinical MRI, predominantly with a receive-only RF coil design in combination with a volume RF coil used for excitation.…”