Toward cardiovascular MRI at 7 T: clinical needs, technical solutions and research promises

ObjectiveTo consider potential clinical needs, technical solutions and research promises of ultrahigh-field strength cardiovascular MR (CMR).MethodsA literature review is given, surveying advantages and disadvantages of CMR at ultrahigh fields (UHF). Key concepts, emerging technologies, practical considerations and applications of UHF CMR are provided. Examples of UHF CMR imaging strategies and their added value are demonstrated, including the numerous unsolved problems. A concluding section explores future directions in UHF CMR.ResultsUHF CMR can be regarded as one of the most challenging MRI applications. Image quality achievable at UHF is not always exclusively defined by signal-to-noise considerations. Some of the inherent advantages of UHF MRI are offset by practical challenges. But UHF CMR can boast advantages over its kindred lower field counterparts by trading the traits of high magnetic fields for increased temporal and/or spatial resolution.ConclusionsCMR at ultrahigh-field strengths is a powerful motivator, since speed and signal may be invested to overcome the fundamental constraints that continue to hamper traditional CMR. If practical challenges can be overcome, UHF CMR will help to open the door to new approaches for basic science and clinical research.

[1]  G J Metzger,et al.  Initial results of cardiac imaging at 7 tesla , 2009, Magnetic resonance in medicine.

[2]  Walter Heindel,et al.  Hazardous situation in the MR bore: induction in ECG leads causes fire , 2003, European Radiology.

[3]  Peter Andersen,et al.  Whole‐body imaging at 7T: Preliminary results , 2009, Magnetic resonance in medicine.

[4]  O Strohm,et al.  Contrast media-enhanced magnetic resonance imaging visualizes myocardial changes in the course of viral myocarditis. , 1998, Circulation.

[5]  Peter Boesiger,et al.  Feasibility of Cardiac Gating Free of Interference With Electro-Magnetic Fields at 1.5 Tesla, 3.0 Tesla and 7.0 Tesla Using an MR-Stethoscope , 2009, Investigative radiology.

[6]  E. Nagel,et al.  Cardiovascular MRI at 3 T , 2007, European radiology.

[7]  D. Sodickson,et al.  Electrodynamic constraints on homogeneity and radiofrequency power deposition in multiple coil excitations , 2009, Magnetic resonance in medicine.

[8]  James C Carr,et al.  ACCF/ACR/SCCT/SCMR/ASNC/NASCI/SCAI/SIR 2006 appropriateness criteria for cardiac computed tomography and cardiac magnetic resonance imaging: a report of the American College of Cardiology Foundation Quality Strategic Directions Committee Appropriateness Criteria Working Group, American College of Ra , 2006, Journal of the American College of Cardiology.

[9]  Thoralf Niendorf,et al.  Cardiac chamber quantification using magnetic resonance imaging at 7 Tesla—a pilot study , 2010, European Radiology.

[10]  J. Schulz-Menger,et al.  Diagnostic performance of cardiovascular magnetic resonance in patients with suspected acute myocarditis: comparison of different approaches. , 2005, Journal of the American College of Cardiology.

[11]  Thoralf Niendorf,et al.  Highly accelerated cardiovascular MR imaging using many channel technology: concepts and clinical applications , 2007, European Radiology.

[12]  R. Lauffer,et al.  Gadolinium(III) Chelates as MRI Contrast Agents: Structure, Dynamics, and Applications. , 1999, Chemical reviews.

[13]  A G Webb,et al.  Simple RF design for human functional and morphological cardiac imaging at 7tesla. , 2009, Journal of magnetic resonance.

[14]  Manesh R. Patel,et al.  ACCF/ACR/SCCT/SCMR/ASNC/NASCI/SCAI/SIR 2006 appropriateness criteria for cardiac computed tomography and cardiac magnetic resonance imaging. A report of the American College of Cardiology Foundation Quality Strategic Directions Committee Appropriateness Criteria Working Group. , 2006, Journal of the American College of Radiology : JACR.

[15]  Christoph Butenweg,et al.  Comparison of left ventricular function assessment using phonocardiogram- and electrocardiogram-triggered 2D SSFP CINE MR imaging at 1.5 T and 3.0 T , 2010, European Radiology.

[16]  Matthew W. Darlison,et al.  Improved survival of thalassaemia major in the UK and relation to T2* cardiovascular magnetic resonance , 2008, Journal of cardiovascular magnetic resonance : official journal of the Society for Cardiovascular Magnetic Resonance.

[17]  J. Hennig,et al.  Inner-Volume-Imaging Using Three-Dimensional Parallel Excitation , 2009 .

[18]  Jürgen Hennig,et al.  Experimental analysis of parallel excitation using dedicated coil setups and simultaneous RF transmission on multiple channels , 2005, Magnetic resonance in medicine.

[19]  Jürgen Hennig,et al.  Images in cardiovascular medicine. In vivo 3-dimensional flow connectivity mapping after extracardiac total cavopulmonary connection. , 2008, Circulation.

[20]  M. Gutberlet,et al.  Influence of high magnetic field strengths and parallel acquisition strategies on image quality in cardiac 2D CINE magnetic resonance imaging: comparison of 1.5 T vs. 3.0 T , 2005, European Radiology.

[21]  M. Stuber,et al.  Initial results on in vivo human coronary MR angiography at 7 T , 2009, Magnetic resonance in medicine.

[22]  J. Schulz-Menger,et al.  Cardiac magnetic resonance monitors reversible and irreversible myocardial injury in myocarditis. , 2009, JACC. Cardiovascular imaging.

[23]  C H Lorenz,et al.  Novel real‐time R‐wave detection algorithm based on the vectorcardiogram for accurate gated magnetic resonance acquisitions , 1999, Magnetic resonance in medicine.

[24]  Amendment to the ICNIRP "Statement on medical magnetic resonance (MR) procedures: protection of patients". , 2009, Health physics.

[25]  Peter Börnert,et al.  Parallel RF transmission in MRI , 2006, NMR in biomedicine.

[26]  Steen Moeller,et al.  B1 destructive interferences and spatial phase patterns at 7 T with a head transceiver array coil , 2005, Magnetic resonance in medicine.

[27]  J. Roelandt,et al.  Images in Cardiovascular Medicine , 2000 .

[28]  E Kanal,et al.  Burns associated with the use of monitoring equipment during MR procedures , 1996, Journal of magnetic resonance imaging : JMRI.

[29]  K. Uğurbil,et al.  Efficient high‐frequency body coil for high‐field MRI , 2004, Magnetic resonance in medicine.

[30]  M. Gutberlet,et al.  Suspected chronic myocarditis at cardiac MR: diagnostic accuracy and association with immunohistologically detected inflammation and viral persistence. , 2008, Radiology.

[31]  C. Higgins,et al.  ECG-synchronized cardiac MR imaging: method and evaluation. , 1985, Radiology.

[32]  P. Börnert,et al.  Transmit SENSE , 2003, Magnetic resonance in medicine.

[33]  Thoralf Niendorf,et al.  Comprehensive Cardiac Magnetic Resonance Imaging at 3.0 Tesla: Feasibility and Implications for Clinical Applications , 2006, Investigative radiology.

[34]  K. Klingel,et al.  Presentation, Patterns of Myocardial Damage, and Clinical Course of Viral Myocarditis , 2006, Circulation.

[35]  Vivek K Goyal,et al.  Specific absorption rate studies of the parallel transmission of inner‐volume excitations at 7T , 2008, Journal of magnetic resonance imaging : JMRI.

[36]  R. Kim,et al.  Contrast-enhanced MRI and routine single photon emission computed tomography (SPECT) perfusion imaging for detection of subendocardial myocardial infarcts: an imaging study , 2003, The Lancet.

[37]  René M. Botnar,et al.  Preliminary report on in vivo coronary MRA at 3 Tesla in humans , 2002, Magnetic resonance in medicine.

[38]  A. Stecco,et al.  Patient safety issues in magnetic resonance imaging: state of the art , 2007, La radiologia medica.

[39]  F. Shellock,et al.  MR procedures: biologic effects, safety, and patient care. , 2004, Radiology.

[40]  John P Stralka,et al.  A prototype RF dosimeter for independent measurement of the average specific absorption rate (SAR) during MRI , 2007, Journal of magnetic resonance imaging : JMRI.

[41]  Roger B. Davis,et al.  Impact of Unrecognized Myocardial Scar Detected by Cardiac Magnetic Resonance Imaging on Event-Free Survival in Patients Presenting With Signs or Symptoms of Coronary Artery Disease , 2006, Circulation.

[42]  Yudong Zhu,et al.  Parallel excitation with an array of transmit coils , 2004, Magnetic resonance in medicine.

[43]  Thoralf Niendorf,et al.  Acoustic method for synchronization of Magnetic Resonance Imaging (MRI) , 2008 .