title: Radiofrequency configuration to facilitate bilateral breast (31) P MR spectroscopic imaging and high-resolution MRI at 7 Tesla.
abstract: OBJECTIVE
  High-resolution MRI combined with phospholipid detection may improve breast cancer grading. Currently, configurations are optimized for either high-resolution imaging or (31) P spectroscopy. To be able to perform both imaging as well as spectroscopy in a single session, we integrated a (1) H receiver array into a (1) H-(31) P transceiver at 7T. To ensure negligible signal loss due to coupling between elements, we investigated the use of a floating decoupling loop to enable bilateral MRI and (31) P MRS.
  
  
  METHODS
  Two quadrature double-tuned radiofrequency coils were designed for bilateral breast MR with active detuning at the (1) H frequency. The two coils were placed adjacent to each other and decoupled for both frequencies with a single resonant floating loop. Sensitivity of the bilateral configuration, facilitating space for a 26-element (1) H receive array, was compared with a transceiver configuration.
  
  
  RESULTS
  The floating loop was able to decouple the elements over 20 dB for both frequencies. Enlargement of the elements, to provide space for the receivers, and the addition of detuning electronics altered the (31) P sensitivity by 0.4 dB.
  
  
  CONCLUSIONS
  Dynamic contrast-enhanced scans of 0.7 mm isotropic, diffusion-weighted imaging, and (31) P MR spectroscopic imaging can be acquired at 7T in a single session as demonstrated in a patient with invasive ductal carcinoma.
authors.affiliation: University Medical Centre Utrecht, department of Radiology, Heidelberglaan 100, 3584CX, Utrecht, the Netherlands.
authors.forename: Tijl A
authors.initials: TA
authors.lastname: van der Velden
authors.affiliation: MR Coils B.V., Grotestraat 260C, 5151BS, Drunen, the Netherlands.
authors.forename: Michel
authors.initials: M
authors.lastname: Italiaander
authors.affiliation: University Medical Centre Utrecht, department of Radiology, Heidelberglaan 100, 3584CX, Utrecht, the Netherlands.
authors.forename: Wybe J M
authors.initials: WJ
authors.lastname: van der Kemp
authors.affiliation: University Medical Centre Utrecht, department of Radiology, Heidelberglaan 100, 3584CX, Utrecht, the Netherlands.
authors.forename: Alexander J E
authors.initials: AJ
authors.lastname: Raaijmakers
authors.affiliation: University Medical Centre Utrecht, department of Radiology, Heidelberglaan 100, 3584CX, Utrecht, the Netherlands.
authors.forename: A M Th
authors.initials: AM
authors.lastname: Schmitz
authors.affiliation: University Medical Centre Utrecht, department of Radiology, Heidelberglaan 100, 3584CX, Utrecht, the Netherlands.
authors.forename: Peter R
authors.initials: PR
authors.lastname: Luijten
authors.affiliation: University Medical Centre Utrecht, department of Radiology, Heidelberglaan 100, 3584CX, Utrecht, the Netherlands.
authors.forename: Vincent O
authors.initials: VO
authors.lastname: Boer
authors.affiliation: University Medical Centre Utrecht, department of Radiology, Heidelberglaan 100, 3584CX, Utrecht, the Netherlands.
authors.forename: Dennis W J
authors.initials: DW
authors.lastname: Klomp
mesh_terms: D000669:Amplifiers, Electronic; D001943:Breast Neoplasms / Q000175:diagnosis*; D018270:Carcinoma, Ductal, Breast / Q000175:diagnosis*; D038524:Diffusion Magnetic Resonance Imaging / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000295:instrumentation*; D009682:Magnetic Resonance Spectroscopy / Q000295:instrumentation*; D008280:Magnetics / Q000295:instrumentation*; D057054:Molecular Imaging / Q000379:methods; D010759:Phosphorus Isotopes / Q000493:pharmacokinetics; D011846:Radio Waves; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014159:Transducers
chemical_list: D010759:Phosphorus Isotopes; D019275:Radiopharmaceuticals
keywords: 1H; 31P; 7 Tesla; RF coils; breast MR; coil array; dual tuned; imaging; spectroscopy