Multiple Parallel Round Leg Design for Quadrature Birdcage Coil in Ultrahigh-Field MRI
- Авторлар: Xu Y.1,2, Wen Q.1,3, Yang H.1, Zhong K.1,4,2
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Мекемелер:
- High Magnetic Field Laboratory, Chinese Academy of Sciences
- University of Science and Technology of China
- University of Chinese Academy of Sciences
- CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences
- Шығарылым: Том 49, № 2 (2018)
- Беттер: 209-216
- Бөлім: Original Paper
- URL: https://journals.rcsi.science/0937-9347/article/view/248014
- DOI: https://doi.org/10.1007/s00723-017-0963-0
- ID: 248014
Дәйексөз келтіру
Аннотация
Copper foil has been widely employed in conventional radio frequency (RF) birdcage coils for magnetic resonance imaging (MRI). However, for ultrahigh-field (UHF) MRI, current density distribution on the copper foil is concentrated on the surface and the edge due to proximity effect. This increases the effective resistance and distorts the circumferential sinusoidal current distribution on the birdcage coils, resulting in low signal-to-noise ratio (SNR) and inhomogeneous distribution of RF magnetic (B1) field. In this context, multiple parallel round wires were proposed as legs of a birdcage coil to optimize current density distribution and to improve the SNR and the B1 field homogeneity. The design was compared with three conventional birdcage coils with different width flat strip surface legs for a 9.4 T (T) MRI system, e.g., narrow-leg birdcage coil (NL), medium-leg birdcage coil (ML), broad-leg birdcage coil (BL) and the multiple parallel round wire-leg birdcage coil (WL). Studies were carried out in in vitro saline phantom as well as in vivo mouse brain. WL showed higher coil quality factor Q and more homogeneous B1 field distribution compared to the other three conventional birdcage coils. Furthermore, WL showed 12, 10 and 13% SNR increase, respectively, compared to NL, ML and BL. It was proposed that conductor’s shape optimization could be an effective approach to improve RF coil performance for UHF MRI.
Авторлар туралы
Yongfeng Xu
High Magnetic Field Laboratory, Chinese Academy of Sciences; University of Science and Technology of China
Email: kzhong@hmfl.ac.cn
ҚХР, Hefei, 230031; Hefei, 230026
Qingqing Wen
High Magnetic Field Laboratory, Chinese Academy of Sciences; University of Chinese Academy of Sciences
Email: kzhong@hmfl.ac.cn
ҚХР, Hefei, 230031; Beijing, 10010
Hongyi Yang
High Magnetic Field Laboratory, Chinese Academy of Sciences
Email: kzhong@hmfl.ac.cn
ҚХР, Hefei, 230031
Kai Zhong
High Magnetic Field Laboratory, Chinese Academy of Sciences; CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences; University of Science and Technology of China
Хат алмасуға жауапты Автор.
Email: kzhong@hmfl.ac.cn
ҚХР, Hefei, 230031; Hefei; Hefei, 230026