Whole body sodium MRI at 3T using an asymmetric birdcage resonator and short echo time sequence

• Verfasst von: Wetterling, Friedrich [VerfasserIn]
• Verfasst von: Corteville, Dominique [VerfasserIn]
• Verfasst von: Kalayciyan, Raffi [VerfasserIn]
• Verfasst von: Konstandin, Simon [VerfasserIn]
• Verfasst von: Nagel, Armin Michael [VerfasserIn]
• Verfasst von: Schad, Lothar R. [VerfasserIn]
• Titel: Whole body sodium MRI at 3T using an asymmetric birdcage resonator and short echo time sequence
• Titelzusatz: first images of a male volunteer
• Verf.angabe: Friedrich Wetterling, Dominique M. Corteville, Raffi Kalayciyan, Andreas Rennings, Simon Konstandin, Armin M. Nagel, Helmut Stark and Lothar R. Schad
• E-Jahr: 2012
• Jahr: 22 June 2012
• Umfang: 13 S.
• Fussnoten: Gesehen am 29.10.2018
• Titel Quelle: Enthalten in: Physics in medicine and biology
• Ort Quelle: Bristol : IOP Publ., 1956
• Jahr Quelle: 2012
• Band/Heft Quelle: 57(2012), 14, Seite 4555-4567
• ISSN Quelle: 1361-6560
• DOI: doi:10.1088/0031-9155/57/14/4555
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1582387389

Abstract

Sodium magnetic resonance imaging ( 23 Na MRI) is a non-invasive technique which allows spatial resolution of the tissue sodium concentration (TSC) in the human body. TSC measurements could potentially serve to monitor early treatment success of chemotherapy on patients who suffer from whole body metastases. Yet, the acquisition of whole body sodium ( 23 Na) images has been hampered so far by the lack of large resonators and the extremely low signal-to-noise ratio (SNR) achieved with existing resonator systems. In this study, a 23 Na resonator was constructed for whole body 23 Na MRI at 3T comprising of a 16-leg, asymmetrical birdcage structure with 34 cm height, 47.5 cm width and 50 cm length. The resonator was driven in quadrature mode and could be used either as a transceiver resonator or, since active decoupling was included, as a transmit-only resonator in conjunction with a receive-only (RO) surface resonator. The relative B 1 -field profile was simulated and measured on phantoms, and 3D whole body 23 Na MRI data of a healthy male volunteer were acquired in five segments with a nominal isotropic resolution of (6 × 6 × 6) mm 3 and a 10 min acquisition time per scan. The measured SNR values in the 23 Na-MR images varied from 9 ± 2 in calf muscle, 15 ± 2 in brain tissue, 23 ± 2 in the prostate and up to 42 ± 5 in the vertebral discs. Arms, legs, knees and hands could also be resolved with applied resonator and short time-to-echo (TE) (0.5 ms) radial sequence. Up to fivefold SNR improvement was achieved through combining the birdcage with local RO surface coil. In conclusion, 23 Na MRI of the entire human body provides sub-cm spatial resolution, which allows resolution of all major human body parts with a scan time of less than 60 min.