title: High-performance radiofrequency coils for (23)Na MRI: brain and musculoskeletal applications.
abstract: (23)Na RF coil design for brain and MSK applications presents a number of challenges, including poor coil loading for arrays of small coils and SNR penalties associated with providing (1)H capability with the same coil. The basics of RF coil design are described, as well as a review of historical approaches to dual tuning. There follows a review of published high performance coil designs for MSK and brain imaging. Several coil designs have been demonstrated at 7T and 3T which incorporate close-fitting receive arrays and in some cases design features which provide (1)H imaging with little penalty to (23)Na sensitivity. The "nested coplanar loop" approach is examined, in which small transmit-receive (1)H elements are placed within each (23)Na loop, presenting only a small perturbation to (23)Na performance and minimizing RF shielding issues. Other designs incorporating transmit-receive arrays for (23)Na and (1)H are discussed including a 9.4 T (23)Na/(1)H brain coil. Great gains in (23)Na SNR have been made with many of these designs, but simultaneously achieving high performance for 1H remains elusive.
authors.affiliation: Center for Advanced Imaging Innovation and Research (CAI2R), New York University Langone Medical Center, New York, NY, 10016, USA.
authors.forename: Graham C
authors.initials: GC
authors.lastname: Wiggins
authors.affiliation: Center for Advanced Imaging Innovation and Research (CAI2R), New York University Langone Medical Center, New York, NY, 10016, USA.
authors.forename: Ryan
authors.initials: R
authors.lastname: Brown
authors.affiliation: Center for Advanced Imaging Innovation and Research (CAI2R), New York University Langone Medical Center, New York, NY, 10016, USA.
authors.forename: Karthik
authors.initials: K
authors.lastname: Lakshmanan
mesh_terms: D001921:Brain / Q000033:anatomy & histology*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000295:instrumentation* / Q000379:methods*; D009141:Musculoskeletal System / Q000033:anatomy & histology*; D011846:Radio Waves; D012964:Sodium / Q000378:metabolism*
chemical_list: D012964:Sodium
keywords: 23Na; RF receive coils; RF transmit coils; array coils; coplanar; dual tuned; sodium