Imaging Division, University Medical Center Utrecht, Utrecht, the Netherlands.
CNRS UMR 5251/University of Bordeaux, Institut de Mathématiques de Bordeaux, Talence, France.
J Magn Reson Imaging. 2018 Mar;47(3):692-701. doi: 10.1002/jmri.25800. Epub 2017 Jun 24.
To demonstrate that fluid filling of the digestive tract improves the performance of respiratory motion-compensated proton resonance frequency shift (PRFS)-based magnetic resonance (MR) thermometry in the pancreas.
In seven volunteers (without heating), we evaluated PRFS thermometry in the pancreas with and without filling of the surrounding digestive tract. All data acquisition was performed at 1.5T, then all datasets were analyzed and compared with three different PRFS respiratory motion-compensated thermometry methods: gating, multibaseline, and referenceless. The temperature precision of the different methods was evaluated by assessing temperature standard deviation over time, while a simulation experiment was used to study the accuracy of the methods.
Without fluid intake, errors in temperature precision in the pancreas up to 10°C were observed for all evaluated methods. After liquid intake, temperature precision improved to median values between 1.8 and 2.9°C. The simulations showed that gating had the lowest accuracy, with errors up to 7°C. Multibaseline and referenceless thermometry performed better, with a median error in the pancreas between -3 and +3°C after fluid intake, for all volunteers.
Preparation of the digestive tract near the pancreas by filling it with fluid improved MR thermometry precision and accuracy for all common respiratory motion-compensated methods evaluated. These improvements are attributed to reducing field inhomogeneity in the pancreas.
2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2018;47:692-701.
证明消化道充盈能提高质子共振频率移动补偿（PRFS）磁共振（MR）测温在胰腺中的性能。
在 7 名志愿者（未加热）中，我们评估了胰腺 PRFS 测温在填充周围消化道和不填充周围消化道时的表现。所有数据采集均在 1.5T 下进行，然后用三种不同的 PRFS 呼吸运动补偿测温方法：门控法、多基线法和无参照法对所有数据集进行分析和比较。通过评估随时间的温度标准差来评估不同方法的温度精度，同时通过模拟实验来研究方法的准确性。
在未摄入液体时，所有评估方法在胰腺中的温度精度误差高达 10°C。摄入液体后，温度精度提高到中位数在 1.8 到 2.9°C 之间。模拟结果表明，门控法的准确性最低，误差高达 7°C。多基线法和无参照法的表现更好，所有志愿者在摄入液体后，胰腺中的中位数误差在-3 到+3°C 之间。
通过填充液体来准备胰腺附近的消化道，提高了所有常用的呼吸运动补偿方法的 MR 测温精度和准确性。这些改进归因于减少了胰腺中的磁场不均匀性。
2 技术效果：1 级 J. Magn. Reson. Imaging 2018;47:692-701.
