TY - JOUR
T1 - Evolution of UHF Body Imaging in the Human Torso at 7T
T2 - Technology, Applications, and Future Directions
AU - Erturk, M. Arcan
AU - Li, Xiufeng
AU - Van De Moortele, Pierre Fancois
AU - Ugurbil, Kamil
AU - Metzger, Gregory J.
N1 - Publisher Copyright:
© 2019 Wolters Kluwer Health, Inc. All rights reserved.
PY - 2019/6/1
Y1 - 2019/6/1
N2 - The potential value of ultrahigh field (UHF) magnetic resonance imaging (MRI) and spectroscopy to biomedical research and in clinical applications drives the development of technologies to overcome its many challenges. The increased difficulties of imaging the human torso compared with the head include its overall size, the dimensions and location of its anatomic targets, the increased prevalence and magnitude of physiologic effects, the limited availability of tailored RF coils, and the necessary transmit chain hardware. Tackling these issues involves addressing notoriously inhomogeneous transmit B1 (B1+) fields, limitations in peak B1+, larger spatial variations of the static magnetic field B0, and patient safety issues related to implants and local RF power deposition. However, as research institutions and vendors continue to innovate, the potential gains are beginning to be realized. Solutions overcoming the unique challenges associated with imaging the human torso are reviewed as are current studies capitalizing on the benefits of UHF in several anatomies and applications. As the field progresses, strategies associated with the RF system architecture, calibration methods, RF pulse optimization, and power monitoring need to be further integrated into the MRI systems making what are currently complex processes more streamlined. Meanwhile, the UHF MRI community must seize the opportunity to build upon what have been so far proof of principle and feasibility studies and begin to further explore the true impact in both research and the clinic.
AB - The potential value of ultrahigh field (UHF) magnetic resonance imaging (MRI) and spectroscopy to biomedical research and in clinical applications drives the development of technologies to overcome its many challenges. The increased difficulties of imaging the human torso compared with the head include its overall size, the dimensions and location of its anatomic targets, the increased prevalence and magnitude of physiologic effects, the limited availability of tailored RF coils, and the necessary transmit chain hardware. Tackling these issues involves addressing notoriously inhomogeneous transmit B1 (B1+) fields, limitations in peak B1+, larger spatial variations of the static magnetic field B0, and patient safety issues related to implants and local RF power deposition. However, as research institutions and vendors continue to innovate, the potential gains are beginning to be realized. Solutions overcoming the unique challenges associated with imaging the human torso are reviewed as are current studies capitalizing on the benefits of UHF in several anatomies and applications. As the field progresses, strategies associated with the RF system architecture, calibration methods, RF pulse optimization, and power monitoring need to be further integrated into the MRI systems making what are currently complex processes more streamlined. Meanwhile, the UHF MRI community must seize the opportunity to build upon what have been so far proof of principle and feasibility studies and begin to further explore the true impact in both research and the clinic.
KW - 7 Tesla
KW - RF coils
KW - RF shimming
KW - body imaging
KW - parallel transmit
KW - ultrahigh field
UR - http://www.scopus.com/inward/record.url?scp=85067802549&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85067802549&partnerID=8YFLogxK
U2 - 10.1097/RMR.0000000000000202
DO - 10.1097/RMR.0000000000000202
M3 - Review article
C2 - 31188271
AN - SCOPUS:85067802549
SN - 0899-3459
VL - 28
SP - 101
EP - 124
JO - Topics in Magnetic Resonance Imaging
JF - Topics in Magnetic Resonance Imaging
IS - 3
ER -