- 著者
- Michiru Kajiwara Tomoyuki Haishi Dwi Prananto Susumu Sasaki Ryohei Kaseda Ichiei Narita Yasuhiko Terada
- 出版者
- Japanese Society for Magnetic Resonance in Medicine
- 雑誌
- Magnetic Resonance in Medical Sciences (ISSN:13473182)
- 巻号頁・発行日
- pp.tn.2021-0094, (Released:2021-12-10)
- 参考文献数
- 19
- 被引用文献数
- 1
23Na-MRI provides information on Na+ content, and its application in the medical field has been highly anticipated. However, for existing clinical 1H-MRI systems, its implementation requires an additional broadband RF transmitter, dedicated transceivers, and RF coils for Na+ imaging. However, a standard medical MRI system cannot often be modified to perform 23Na imaging. We have developed an add-on crossband RF repeater system that enables 23Na-MRI simply by inserting it into the magnet bore of an existing 1H MRI. The three axis gradient fields controlled by the 1H-MRI system were directly used for 23Na imaging without any deformation. A crossband repeater is a common technique used for amateur radio. This concept was proven by a saline solution phantom and in vivo mouse experiments. This add-on RF platform is applicable to medical 1H MRI systems and can enhance the application of 23Na-MRI in clinical usage.
- 著者
- Masayuki Yamaguchi Kosuke Kojo Mizuki Akatsuka Tomoyuki Haishi Tatsushi Kobayashi Takahito Nakajima Hiroyuki Nishiyama Hirofumi Fujii
- 出版者
- Japanese Society for Magnetic Resonance in Medicine
- 雑誌
- Magnetic Resonance in Medical Sciences (ISSN:13473182)
- 巻号頁・発行日
- pp.tn.2021-0130, (Released:2022-03-23)
- 参考文献数
- 13
We have developed a new device, consisting of a 3-cm RF coil and an immobilizer, to acquire high-resolution MR images of the testis. With the approval of our institutional review board, we conducted an MRI study on a cohort of healthy volunteers to test this device. With the participants in the supine position, we placed the dedicated immobilizer and RF coil on the scrotum for typically no more than 3 min. Subsequently, T2-weighted images were acquired with an in-plane resolution of 117 µm using a 3-T MR scanner and the periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) sequence. The total scan time ranged from 12 to 30 min (average 20 min). High-resolution MR images of the testis were acquired without deterioration by motion artifacts. Our results showed that the combined use of a small RF coil and an immobilizer is a feasible option for acquiring high-resolution MR images of the testis.
- 著者
- Yoshimasa MATSUDA Shinya ONO Yosuke OTAKE Shinya HANDA Katsumi KOSE Tomoyuki HAISHI Shigeto YAMADA Chikako UWABE Kohei SHIOTA
- 出版者
- 日本磁気共鳴医学会
- 雑誌
- Magnetic Resonance in Medical Sciences (ISSN:13473182)
- 巻号頁・発行日
- vol.6, no.3, pp.139-146, 2007 (Released:2007-11-20)
- 参考文献数
- 15
- 被引用文献数
- 18 38
Using 4 and 8-channel super-parallel magnetic resonance (MR) microscopes with a horizontal bore 2.34T superconducting magnet developed for 3-dimensional MR microscopy of the large Kyoto Collection of Human Embryos, we acquired T1-weighted 3D images of 1204 embryos at a spatial resolution of (40 μm)3 to (150 μm)3 in about 2 years. Similarity of image contrast between the T1-weighted images and stained anatomical sections indicated that T1-weighted 3D images could be used for an anatomical 3D image database for human embryology.