Non-invasive quantification of small bowel water content by MRI: a validation study
Non-invasive quantification of small bowel water content by MRI: a validation study
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DOI：
10.1088/0031-9155/52/23/009
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发表时间：
2007-12-07
影响因子：
3.5
通讯作者：
Gowland, P. A.
中科院分区：
文献类型：
--
作者：
Hoad, C. L.;Marciani, L.;Gowland, P. A.
在消化食物的过程中，小肠会有大量的水流过，但到目前为止，测量这些水需要有创插管技术。本文介绍了一种非侵入性磁共振成像（MRI）技术，用于测量小肠水含量已被验证使用鼻十二指肠输液。对18名健康志愿者进行插管，通过MRI验证插管位置。在基线MRI扫描后，每名志愿者接受8次40 ml不可吸收甘露醇和生理盐水的推注，并在每次推注后进行MRI扫描。使用的MRI序列是一个改编的磁共振胰胆管造影序列。对图像数据进行阈值处理，以允许受试者内和受试者间信号变化。然后将MRI测量体积与已知输注体积进行比较。这种MRI技术提供了良好的小肠图像，与使用钡造影剂的常规放射学获得的图像非常相似。测量的MRI体积和输注体积之间的平均差异为2%，标准差为10%。观察员之间一致性的最大95%限度为-15%至+17%，而同一操作员在不同情况下的测量结果仅相差4%。这项新技术现在可以应用于研究由于胃肠道疾病或药物干预引起的小肠液体吸收和分泌的变化。
Substantial water fluxes across the small intestine occur during digestion of food, but so far measuring these has required invasive intubation techniques. This paper describes a non-invasive magnetic resonance imaging (MRI) technique for measuring small bowel water content which has been validated using naso-duodenal infusion. Eighteen healthy volunteers were intubated, with the tube position being verified by MRI. After a baseline MRI scan, each volunteer had eight 40 ml boluses of a non-absorbable mannitol and saline solution infused into their proximal small bowel with an MRI scan being acquired after each bolus. The MRI sequence used was an adapted magnetic resonance cholangiopancreatography sequence. The image data were thresholded to allow for intra- and inter-subject signal variations. The MRI measured volumes were then compared to the known infused volumes. This MRI technique gave excellent images of the small bowel, which closely resemble those obtained using conventional radiology with barium contrast. The mean difference between the measured MRI volumes and infused volumes was 2% with a standard deviation of 10%. The maximum 95% limits of agreement between observers were -15% to +17% while measurements by the same operator on separate occasions differed by only 4%. This new technique can now be applied to study alterations in small bowel fluid absorption and secretion due to gastrointestinal disease or drug intervention.