Huang Y-F, Hsieh T-J, Chen Y-J, Chen H-S, Kuo Y-T, Yang Y-H
Department of Medical Imaging, Kaohsiung Municipal Ta-Tung Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan.
Department of Medical Imaging, Chi Mei Medical Center, Tainan, Taiwan.
Clin Radiol. 2018 Oct;73(10):907.e1-907.e7. doi: 10.1016/j.crad.2018.07.100. Epub 2018 Aug 9.
To quantify in vitro the T1-weighted (T1W) expression of iodinated contrast media (CM), and to compare the in vivo performances of iodinated CM and gadolinium-based CM for T1W direct magnetic resonance imaging (MRI) arthrography.
An in vitro study on a 1.5 T MRI system was performed using Gd-DOTA, a mixture of iopromide and Gd-DOTA, and iopromide alone. The fat-suppressed (FS) T1W signal intensities were measured and analysed. In an in vivo study, 15 normal rabbits were used to compare the expression of iopromide (370 mg iodine/ml), and the mixture of iopromide and diluted Gd-DOTA. In nine of the 15 rabbits, extra-articular administrations of CM were performed to mimic the situation of CM leak. The rabbits were scanned on a 1.5 T MRI system, and the FS T1W sequence and an axial iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL) T1W sequence were acquired. Signal intensities were measured and signal-to-noise ratios (SNR) were analysed.
In the in vitro study, a higher SNR was noted in a higher concentration of iopromide, and the highest SNR of iopromide was 45.9% of that of Gd-DOTA. In the in vivo study, the iopromide and the mixture were well identified in all rabbits. The SNRs of the intra-articular and extra-articular iopromide and the mixture were significantly higher than the SNR of the muscles in the FS T1W images (all, p<0.01) and the IDEAL images (all, p<0.01).
A high-concentration iodinated CM can provide good imaging quality for T1W direct MRI arthrography, and may be an alternative option in certain clinical situations.
在体外量化碘化造影剂（CM）的T1加权（T1W）表现，并比较碘化CM和钆基CM在T1W直接磁共振成像（MRI）关节造影中的体内性能。
在1.5T MRI系统上进行体外研究，使用钆喷酸葡胺（Gd-DOTA）、碘普罗胺与Gd-DOTA的混合物以及单独的碘普罗胺。测量并分析脂肪抑制（FS）T1W信号强度。在体内研究中，使用15只正常兔比较碘普罗胺（370mg碘/毫升）以及碘普罗胺与稀释Gd-DOTA混合物的表现。在15只兔中的9只，进行关节外注射CM以模拟CM渗漏情况。对兔在1.5T MRI系统上进行扫描，采集FS T1W序列和具有回波不对称性和最小二乘估计的水和脂肪轴向迭代分解（IDEAL）T1W序列。测量信号强度并分析信噪比（SNR）。
在体外研究中，碘普罗胺浓度越高，SNR越高，碘普罗胺的最高SNR为Gd-DOTA的45.9%。在体内研究中，所有兔中碘普罗胺及其混合物均能被很好地识别。在FS T1W图像（均为p<0.01）和IDEAL图像（均为p<0.01）中，关节内和关节外碘普罗胺及其混合物的SNR均显著高于肌肉的SNR。
高浓度碘化CM可为T1W直接MRI关节造影提供良好的成像质量，在某些临床情况下可能是一种替代选择。
