Shibukawa Shuhei, Niwa Tetsu, Miyati Tosiaki, Ogino Tetsuo, Yoshimaru Daisuke, Kuroda Kagayaki
Department of Radiological Technology, Faculty of Health Science, Juntendo University, Bunkyo-Ku, Tokyo, Japan.
Department of Radiology, Tokai University School of Medicine, Isehara, Kanagawa, Japan.
Phys Med Biol. 2021 Dec 16;66(24). doi: 10.1088/1361-6560/ac3fff.
To reduce the determination errors of CSF pulsation in diffusion-weighted image (DWI) thermometry, we investigated whether applying second-order motion compensation diffusion tensor imaging (2nd-MC DTI) and fractional anisotropy (FA) processing improves the measurement of intracranial cerebrospinal fluid (CSF) temperature. In a phantom study, we investigated the relationship between temperature and FA in artificial CSF (ACSF) to determine the threshold for FA processing. The calculated temperatures of ACSF were compared with those of water. In a human study, 18 healthy volunteers were scanned using conventional DTI (c-DTI) and 2nd-MC DTI on a 3.0 T magnetic resonance imaging (MRI) system. A temperature map was created using diffusion coefficients from each DWI with/without FA processing. The temperatures of intracranial CSF were compared between each DTI image using Welch's analysis of variance and Games-Howell's multiple comparisons. In the phantom study, FA did not exceed 0.1 at any temperature. Consequently, pixels exceeding the threshold of 0.1 were removed from the temperature map. Intracranial CSF temperatures significantly differed between the four methods ( < 0.0001). The lowest temperature was 2nd-MC DTI with FA processing (mean, 35.62 °C), followed in order by c-DTI with FA processing (mean, 36.16 °C), 2nd-MC DTI (mean, 37.08 °C), and c-DTI (mean, 39.08 °C; < 0.01 for each). Because the calculated temperature of ACSF was estimated to be lower than that of water, the temperature of 2nd-DTI with FA processing was considered reasonable. The method of 2nd-MC DTI with FA processing enabled determining intracranial CSF temperature with a reduction in CSF pulsation.
为了减少扩散加权成像（DWI）测温中脑脊液脉动的测定误差，我们研究了应用二阶运动补偿扩散张量成像（2nd-MC DTI）和分数各向异性（FA）处理是否能改善颅内脑脊液（CSF）温度的测量。在一项体模研究中，我们研究了人工脑脊液（ACSF）中温度与FA之间的关系，以确定FA处理的阈值。将计算出的ACSF温度与水的温度进行比较。在一项人体研究中，对18名健康志愿者在3.0 T磁共振成像（MRI）系统上使用传统DTI（c-DTI）和2nd-MC DTI进行扫描。使用有/无FA处理的每个DWI的扩散系数创建温度图。使用Welch方差分析和Games-Howell多重比较对每个DTI图像之间的颅内CSF温度进行比较。在体模研究中，任何温度下FA均未超过0.1。因此，将超过阈值0.1的像素从温度图中去除。四种方法之间的颅内CSF温度存在显著差异（<0.0001）。最低温度是采用FA处理的2nd-MC DTI（平均35.62℃），其次是采用FA处理的c-DTI（平均36.16℃）、2nd-MC DTI（平均37.08℃）和c-DTI（平均39.08℃；每种方法之间<0.01）。由于估计ACSF的计算温度低于水的温度，因此采用FA处理的2nd-DTI温度被认为是合理的。采用FA处理的2nd-MC DTI方法能够在减少CSF脉动的情况下测定颅内CSF温度。
