MR电影对正常小肠运动功能定量评估的应用价值

目的探讨MR电影技术定量评估正常小肠运动功能的可行性。材料与方法运用美国GE公司MR Discovery 750HD 3.0 T扫描仪,采用32通道Body线圈,对2012年10月至2014年3月间44名肠道志愿者进行MR口服造影扫描,在不憋气状态下进行时间为2 min的MR电影序列扫描。将采集的电影图像传送至ADW 4.5工作站,并对每帧图像中左上腹及右下腹两段肠管的肠腔管径进行测量。通过绘制时间-肠腔管径曲线进一步对每段肠管的最大肠腔管径,收缩频率、收缩周期以及间歇期进行测定。结果所有志愿者均完成了检查。一共对86段充盈良好的小肠肠管进行了定量分析。所有肠段均存在间歇期。左上腹及右下腹两段肠管间的最大肠腔管径、收缩频率、收缩周期和间歇期分别为（17.66±2.27）mm、（8.64±0.69）s、（3.03±0.61）min、（54.19±15.10）s和（17.42±1.87）mm、（8.75±0.77）s、（3.86±0.54）min、（47.47±15.82）s。两段肠管间的收缩频率以及间歇期存在统计学差异（P〈0.01）。结论 MR电影能够对正常小肠的蠕动功能状况进行定量评估。理论上在了解正常小肠运动特征的基础上,可以运用MR电影这项无创的检查方法对器质性以及功能性小肠疾病患者异常的小肠运动状况进行进一步的研究。

Quantitative assessment of small bowel motility in healthy individuals using MR cine

Objective： The aim of this study was to evaluate the small bowel motility in healthy individuals using MR cine. Materials and Methods： From Oct. 2012 to Mar. 2014, 44 healthy individuals were included in this study. A two minutes MR cine sequence was performed on each individual with no breath-hold using3.0 TMR（GE 750 Dicovery）. Time-caliber graph was plotted on two selected small bowel segments at left upper quadrant and right lower quadrant on each image to obtain the maximum luminal diameter, contraction period, frequency and duration of pause. Results： All subjects were tolerated to the examination without complications. 86 small bowel segments were measured on MR cine images. Duration of pause existed in all selected small bowel segments. The maximum luminal diameter, contraction period, frequency and duration of pause on left upper quadrant and right lower quadrant were（17.66±2.27） mm,（8.64±0.69） s,（3.03±0.61） min,（54.19±15.10） s and（17.42±1.87） mm,（8.75±0.77） s,（3.86±0.54） min,（47.47±15.82） s. The difference of frequency and duration of pause between two selected small bowel segments was statistically significant. Conclusions： MR cine enables us to evaluate the small bowel motility quantitatively and noninvasively. Further study could be made on the impaired peristalsis on different kinds of functional or organic small bowel diseases based on the characterization of the normal small bowel motility.