Automated tuning of an eight-channel cardiac transceive array at 7 tesla using piezoelectric actuators

Ultra‐high field (UHF) MR scanning in the body requires novel coil designs due to B1 field inhomogeneities. In the transverse electromagnetic field (TEM) design, maximum B1 transmit power can only be achieved if each individual transmit element is tuned and matched for different coil loads, which requires a considerable amount of valuable scanner time.

[1]  Warren J Manning,et al.  Clinical indications for cardiovascular magnetic resonance (CMR): Consensus Panel report. , 2004, Journal of cardiovascular magnetic resonance : official journal of the Society for Cardiovascular Magnetic Resonance.

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

[3]  Hoby P Hetherington,et al.  Modified perturbation method for transverse electromagnetic (TEM) coil tuning and evaluation , 2003, Magnetic resonance in medicine.

[4]  Robin M Heidemann,et al.  Generalized autocalibrating partially parallel acquisitions (GRAPPA) , 2002, Magnetic resonance in medicine.

[5]  Gabor Fichtinger,et al.  MRI Compatibility of Robot Actuation Techniques - A Comparative Study , 2008, MICCAI.

[6]  M. Cerqueira,et al.  Standardized myocardial segmentation and nomenclature for tomographic imaging of the heart. A statement for healthcare professionals from the Cardiac Imaging Committee of the Council on Clinical Cardiology of the American Heart Association. , 2002, Circulation.

[7]  Yi Wang,et al.  MRI compatibility evaluation of a piezoelectric actuator system for a neural interventional robot , 2009, 2009 Annual International Conference of the IEEE Engineering in Medicine and Biology Society.

[8]  Stefan Neubauer,et al.  Inversion recovery at 7 T in the human myocardium: Measurement of T1, inversion efficiency and B1+ , 2013, Magnetic resonance in medicine.

[9]  M. Cerqueira,et al.  Standardized myocardial segmentation and nomenclature for tomographic imaging of the heart: A statement for healthcare professionals from the Cardiac Imaging Committee of the Council on Clinical Cardiology of the American Heart Association , 2002, The international journal of cardiovascular imaging.

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

[11]  M. Cerqueira,et al.  Standardized myocardial segmentation and nomenclature for tomographic imaging of the heart. A statement for healthcare professionals from the Cardiac Imaging Committee of the Council on Clinical Cardiology of the American Heart Association. , 2002, Journal of nuclear cardiology : official publication of the American Society of Nuclear Cardiology.

[12]  Fritz Schick,et al.  Whole-body MRI at high field: technical limits and clinical potential , 2005, European Radiology.

[13]  K Ugurbil,et al.  Comparison between eight‐ and sixteen‐channel TEM transceive arrays for body imaging at 7 T , 2012, Magnetic resonance in medicine.

[14]  Jullie W Pan,et al.  High frequency volume coils for clinical NMR imaging and spectroscopy , 1994, Magnetic resonance in medicine.

[15]  M. van Buchem,et al.  Improvements in high‐field localized MRS of the medial temporal lobe in humans using new deformable high‐dielectric materials , 2011, NMR in biomedicine.

[16]  Homayoon Oraizi.  Impedance Matching and BALUNs , 2015 .

[17]  Thoralf Niendorf,et al.  Toward cardiovascular MRI at 7 T: clinical needs, technical solutions and research promises , 2010, European Radiology.

[18]  Douglas C Noll,et al.  Reduction of transmitter B1 inhomogeneity with transmit SENSE slice‐select pulses , 2007, Magnetic resonance in medicine.

[19]  P A Bottomley,et al.  RF magnetic field penetration, phase shift and power dissipation in biological tissue: implications for NMR imaging. , 1978, Physics in medicine and biology.

[20]  S Maderwald,et al.  Time‐interleaved acquisition of modes: An analysis of SAR and image contrast implications , 2012, Magnetic resonance in medicine.

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

[22]  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.

[23]  L. Shaw,et al.  Journal of Cardiovascular Magnetic Resonance Clinical Indications for Cardiovascular Magnetic Resonance (cmr): Consensus Panel Report , 2022 .

[24]  Mark E Ladd,et al.  RF excitation using time interleaved acquisition of modes (TIAMO) to address B1 inhomogeneity in high‐field MRI , 2010, Magnetic resonance in medicine.

[25]  G. Metzger,et al.  Local B1+ shimming for prostate imaging with transceiver arrays at 7T based on subject‐dependent transmit phase measurements , 2008, Magnetic resonance in medicine.

[26]  Mark E Ladd,et al.  Mitigation of B1+ inhomogeneity on single‐channel transmit systems with TIAMO , 2013, Magnetic resonance in medicine.

[27]  T. Vaughan,et al.  7 Tesla (T) human cardiovascular magnetic resonance imaging using FLASH and SSFP to assess cardiac function: validation against 1.5 T and 3 T. , 2012, NMR in biomedicine.