■虽然标准的临床磁共振(MR)小肠造影可以检测炎症性肠病,在决定医疗和手术治疗之间的价值有限。或者,肠道MR弹性成像有可能为治疗决策提供更多信息;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然难以捉摸。因此,我们的目的是研究口服造影剂引起的肠扩张对健康志愿者末端回肠粘弹性的影响。
■在这项前瞻性试点研究中,20名健康志愿者(33.2±8.2岁;10名男性,10名女性)使用1.5特斯拉的单次自旋回波回波平面成像序列和40、50、60和70Hz的驱动频率进行了多频MR弹性成像。剪切波速图(c,单位为ms-1)和损耗角(φ,单位为rad),表示刚度和粘性特性,分别,使用断层弹性成像数据处理生成。在摄入1,000mL的2%甘露醇溶液作为口服造影剂之前和之后,对志愿者进行了扫描。
■与之前相比,回肠末端生物力学特性没有显着差异口服造影剂后(平均c:1.47±0.24vs.1.40±0.25ms-1,P=0.37;平均值φ:0.70±0.12rad与0.68±0.12rad,P=0.61)。此外,口服对比剂前后MR弹性成像参数之间无统计学意义(c:r=0.22,P=0.36;φ:r=0.24,P=0.30)。
■这项研究的结果表明,肠道MR弹性成像对MR弹性成像确定的末端回肠的生物力学组织特性没有系统影响。因此,未来的研究方案在使用或不使用口服对比剂的情况下似乎是可行的.
UNASSIGNED: 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.
UNASSIGNED: 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 (c in ms-1) and loss angle (φ 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.
UNASSIGNED: There was no significant difference in terminal ileum biomechanical properties before vs. after ingestion of an oral contrast agent (mean c: 1.47±0.24 vs. 1.40±0.25 ms-1 with P=0.37; mean φ: 0.70±0.12 rad vs. 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 (c: r=0.22, P=0.36; φ: r=0.24, P=0.30).
UNASSIGNED: 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.