Ro Sa-Ra, Loch Florian N, Siegmund Britta, Kühl Anja A, Neumann Gero-Mathias, Hamm Bernd, Braun Jürgen, Sack Ingolf, Reiter Rolf
Department of Radiology, Charité - Universitätsmedizin Berlin, Berlin, Germany.
Institute for Diagnostic and Interventional Radiology, Nuclear Medicine and Molecular Imaging, HELIOS Emil von Behring, Academic Educational Hospital of Charité - Universitätsmedizin Berlin, Berlin, Germany.
Quant Imaging Med Surg. 2024 Aug 1;14(8):5973-5982. doi: 10.21037/qims-24-101. Epub 2024 Jul 26.
While standard clinical magnetic resonance (MR) enterography can detect inflammatory bowel disease, it is of limited value in deciding between medical versus surgical treatment. Alternatively, intestinal MR elastography has the potential to contribute additional information to therapeutic decision-making; however, the influence of bowel distension by oral contrast agent on viscoelastic tissue properties remains elusive. Therefore, we aimed to investigate the influence of oral contrast agent-induced bowel distension on the viscoelastic properties of the terminal ileum in healthy volunteers.
In this prospective pilot study, 20 healthy volunteers (33.2±8.2 years; 10 men, 10 women) underwent multifrequency MR elastography using a single-shot spin-echo echo planar imaging sequence at 1.5 Tesla and drive frequencies of 40, 50, 60 and 70 Hz. Maps of shear wave speed ( in ms) and loss angle ( in rad), representing stiffness and viscous properties, respectively, were generated using tomoelastography data processing. The volunteers were scanned before and after ingestion of 1,000 mL of 2% mannitol solution as oral contrast agent.
There was no significant difference in terminal ileum biomechanical properties before after ingestion of an oral contrast agent (mean : 1.47±0.24 1.40±0.25 ms with P=0.37; mean : 0.70±0.12 rad 0.68±0.12 rad with P=0.61). Moreover, there was no statistically significant correlation between MR elastography parameters before and after the ingestion of oral contrast (: =0.22, P=0.36; : =0.24, P=0.30).
The results of this study suggest that bowel distension for intestinal MR elastography has no systematic effect on the biomechanical tissue properties of the terminal ileum determined by MR elastography. Therefore, future study protocols appear feasible with or without oral contrast agents.
虽然标准临床磁共振（MR）小肠造影可检测炎症性肠病，但在决定药物治疗还是手术治疗方面价值有限。相比之下，肠道MR弹性成像有可能为治疗决策提供额外信息；然而，口服造影剂引起的肠扩张对粘弹性组织特性的影响仍不清楚。因此，我们旨在研究口服造影剂引起的肠扩张对健康志愿者回肠末端粘弹性特性的影响。
在这项前瞻性初步研究中，20名健康志愿者（33.2±8.2岁；10名男性，10名女性）在1.5特斯拉磁场强度下，使用单次激发自旋回波平面回波成像序列，以40、50、60和70赫兹的驱动频率接受多频MR弹性成像检查。使用弹性成像数据处理生成分别代表刚度和粘性特性的剪切波速度图（单位为m/s）和损耗角图（单位为rad）。志愿者在摄入1000毫升2%甘露醇溶液作为口服造影剂前后接受扫描。
摄入口服造影剂前后，回肠末端生物力学特性无显著差异（平均剪切波速度：1.47±0.24 m/s对1.40±0.25 m/s，P = 0.37；平均损耗角：0.70±0.12 rad对0.68±0.12 rad，P = 0.61）。此外，摄入口服造影剂前后MR弹性成像参数之间无统计学显著相关性（剪切波速度：r = 0.22，P = 0.36；损耗角：r = 0.24，P = 0.30）。
本研究结果表明，用于肠道MR弹性成像的肠扩张对MR弹性成像确定的回肠末端生物力学组织特性无系统性影响。因此，无论有无口服造影剂，未来的研究方案似乎都是可行的。
