@article{oai:repo.qst.go.jp:00078081,
 author = {Hossain, Akram and Obata, Takayuki and Yamaya, Taiga and Hossain, Akram and Obata, Takayuki and Yamaya, Taiga},
 issue = {2},
 journal = {Magnetic resonance in medical sciences : MRMS : an official journal of Japan Society of Magnetic Resonance in Medicine},
 month = {Nov},
 note = {We proposed and developed a new microstrip transmission line radiofrequency (RF) coil for a positron emission tomography (PET) insert for MRI, which has low electrical interactions with PET shield boxes. We performed imaging experiments using a single-channel and a four-channel proposed RF coils for proof-of-concept.
Methods: A conventional microstrip coil consists of a microstrip conductor, a ground conductor, and a dielectric between the two conductors. We proposed a microstrip coil for the PET insert that replaced the conventional single-layer ground conductor with the RF shield of the PET insert. A dielectric material, which could otherwise attenuate gamma photons radiated from the PET imaging tracer, was not used. As proof-of-concept, we compared conventional and the proposed single-channel coils. To study multichannel performance, we further developed a four-channel proposed RF coil. Since the MRI system had a single-channel transmission port, an interfacing four-way RF power division circuit was designed. The coils were implemented as both RF transmitters and receivers in a cylindrical frame of diameter 150 mm. Coil bench performances were tested with a network analyzer (Rohde & Schwarz, Germany), and a homogeneous phantom study was conducted for gradient echo imaging and RF eld (B1) mapping in a 3T clinical system (Verio, Siemens, Erlangen, Germany).
Results: For all coils, the power reflection coefficient was below −30 dB, and the transmission coefficients in the four-channel configuration were near or below −20 dB. The comparative single-channel coil study showed good similarity between the conventional and proposed coils. The gradient echo image of the four- channel coil showed expected flashing image intensity near the coils and no phase distortion was visible. Transmit B1 field map resembled the image performance.
comparative single-channel coil study showed good similarity between the conventional and proposed coils. The gradient echo image of the four- channel coil showed expected flashing image intensity near the coils and no phase distortion was visible. Transmit B1 field map resembled the image performance.},
 pages = {147--153},
 title = {Microstrip Transmission Line RF Coil for a PET/MRI Insert.},
 volume = {19},
 year = {2019}
}