Fast magnetic resonance imaging for analysis of gastrointestinal function in health and disease

应用快速磁共振(MR)成像技术分析健康和疾病患者胃肠道功能。使用4.7T磁共振波谱仪(Biospec ABX 47/40，Bruker)和鸟笼射频线圈(内径分别为10和20 em)，对兔食道/狗胃和大鼠胰腺进行了IH成像，以达到三个主要目标：(1)成像速度，(2)长期记录和(3)高分辨率(磁共振显微镜)。通过快速梯度回波成像(Snapshot)获取动物的横断面、矢状面和冠状面图像。用Snapshot方法(FOV225×2 mm数据矩阵96×2，层厚6 mm，TR3.4ms，TE 1.9ms，329ms/图像)清晰显示8.3 cm/S的食道蠕动。同步测压分析证实MR图像为食道收缩。用实时磁共振图像重建系统和录像机(MR视频系统)连续记录狗胃内充满0.3%柠檬酸铁铵的情况。胃蠕动实时图像可在0.45 S/像下记录20min以上(视野300~2 mm，矩阵128~2 mm，厚度6 mm，TR3.4ms，TE 1.8ms)。对急性实验性胰腺炎大鼠胰腺进行MR扫描(FOV 100 mm，基质256^2，厚度3 mm，TR6.8ms，TE3.5ms)，间隔5~7天，连续1个月，不控制呼吸。胰腺炎性改变和囊性病变的空间和时间发展可显示为三维图像。

Fast magnetic resonance (MR) imaging techniques were applied to analyze the function of the gastrointestinal tract in health and disease. iH imaging of the rabbit esophagus/dog stomach and rat pancreas was carried out using a 4.7 T magnetic resonance spectrometer (Biospec ABX 47/40, Bruker) with bird-cage RF coils (inner diameters of 10 and 20 em) to achieve three main objectives ; (1) speed of imaging, (2) long-term recording and (3) high resolution (MRmicroscopy). Transverse, sagittal and coronal images of the animals were taken by fast gradient-echo imaging (Snapshot).1. Esophageal peristaltic movement at 8.3 cm/s was clearly visualized by Snapshot method (FOV 225^2 mm data matrix 96^2, slice thickness 6 mm, TR 3.4 ms, TE 1.9 ms, 329 ms/image). Simultaneous manometric analysis confirmed MR image was esophageal contraction.2. A continuous recording of the dog stomach filled with 0.3% ferric ammonium citrate,was carried out using a real-time MR image reconstruction system and a video recorder (MR video system). Real-time images of gastric peristaltic movement could be recorded at 0.45 s/image for over 20 min (FOV 300^2mm, matrix 128^2, thickness 6 mm, TR 3.4 ms, TE 1.8 ms).3. MR imagingofthe rat pancreas (FOV 100 mm, matrix 256^2, thickness 3 mm, TR 6.8 ms, TE 3.5 ms) after acute experimental pancreatitis was successfully conducted at 5-7 days intervals for one month without controlling breathing. Inflammatory changes of the pancreas and the spatial and temporal development of a cyst could be seen as three dimensional images.