Okada Hiroki, Koori Norikazu, Shimizu Hatsune, Yamamoto Shohei, Komatsuzaki Tetsuya, Fuse Hiraku, Sasaki Kota, Miyakawa Shin, Yasue Kenji, Takahashi Masato
Department of Radiology, Chiba University Hospital, 1-8-1 Inohana, Chuo-ku, Chiba-shi, Chiba, 260-8677, Japan.
Department of Radiological Technology, Faculty of Medical Technology, Niigata University of Health and Welfare, 1398 Shimami-cho, Niigata, Niigata, 950-3198, Japan.
Radiol Phys Technol. 2025 Jun;18(2):469-476. doi: 10.1007/s12194-025-00900-7. Epub 2025 Mar 23.
The T and T values of magnetic resonance imaging phantoms used by researchers should be equivalent to those of the target tissue. However, this is difficult to achieve because of variations in the phantoms depending on the type and concentration of contrast agents and coagulants. The aim of this study was to elucidate the utility of a determination equation derived using the relaxivity of the contrast agent and coagulant. We prepared phantoms using 0.05-10 mmol L contrast agent (Gadovist; Bayer Yakuhin, Ltd., Osaka, Japan) and 0.1-5.0 wt% agar (agar, powder [010-15815]; Fujifilm Wako Pure Chemical Corporation, Osaka, Japan) and measured their T and T values. Determination equations for T and T values were derived using the relaxivity calculated from the T and T values of the contrast agent and coagulant. Subsequently, the determined values were compared with the measured values. The error rate of the determined T and T values were 7.66 ± 6.60% and 5.66 ± 4.05%, respectively, with correlation coefficients of 0.996 and 0.999. These results indicate that this method enables easy and highly accurate estimation of T and T values in MRI phantoms.
研究人员使用的磁共振成像体模的T1和T2值应与目标组织的T1和T2值相当。然而，由于体模会因造影剂和凝固剂的类型及浓度不同而有所变化，所以这一点很难实现。本研究的目的是阐明利用造影剂和凝固剂的弛豫率推导的测定方程的实用性。我们使用0.05 - 10 mmol/L造影剂（钆布醇；拜耳药业株式会社，日本大阪）和0.1 - 5.0 wt%琼脂（琼脂，粉末状[010 - 15815]；富士胶片和光纯药株式会社，日本大阪）制备体模，并测量其T1和T2值。利用从造影剂和凝固剂的T1和T2值计算出的弛豫率，推导出T1和T2值的测定方程。随后，将测定值与测量值进行比较。测定的T1和T2值的误差率分别为7.66±6.60%和5.66±4.05%，相关系数分别为0.996和0.999。这些结果表明，该方法能够轻松且高精度地估算MRI体模中的T1和T2值。
