Wesbey G E, Brasch R C, Goldberg H I, Engelstad B L, Moss A A
Magn Reson Imaging. 1985;3(1):57-64. doi: 10.1016/0730-725x(85)90009-8.
Delineation of the gastrointestinal tract in magnetic resonance imaging (MRI) remains a problem. Ferric ammonium citrate is paramagnetic, producing a high MRI signal intensity by virtue of its spin-lattice (T1) relaxation rate enhancement properties. Water is diamagnetic, producing a low MRI signal intensity, especially with short TR and TE times. To compare efficacy for gastrointestinal contrast alteration, ferric ammonium citrate was administered to 18 patients and water was given to 10 patients. Spin-echo imaging at 0.35T was performed after administration of these agents. Ferric ammonium citrate produced high signal intensity within the esophagus, stomach, duodenum, and small intestine that aided in the differentiation of the gastrointestinal tract from adjacent tumors, vessels, and viscera. Delineation of the gut wall was superior using ferric ammonium citrate compared to that produced by water. Delineation of the margins of the pancreas, liver, and kidney from adjacent gastrointestinal tract was also better with ferric ammonium citrate. Optimal distinction between bowel and fat was better with water. Longer TE times (75 to 200 ms) may allow improved contrast between gut and intrabdominal fat using ferric ammonium citrate.
磁共振成像（MRI）中胃肠道的描绘仍是一个问题。柠檬酸铁铵具有顺磁性，凭借其自旋晶格（T1）弛豫率增强特性产生高MRI信号强度。水具有抗磁性，产生低MRI信号强度，尤其是在短TR和TE时间时。为比较胃肠道对比改变的效果，对18例患者给予柠檬酸铁铵，对10例患者给予水。给予这些药剂后进行0.35T自旋回波成像。柠檬酸铁铵在食管、胃、十二指肠和小肠内产生高信号强度，有助于将胃肠道与相邻肿瘤、血管和内脏区分开来。与水相比，使用柠檬酸铁铵时肠壁的描绘更佳。使用柠檬酸铁铵时，胰腺、肝脏和肾脏与相邻胃肠道之间边界的描绘也更好。用水时肠道与脂肪之间的最佳区分更好。较长的TE时间（75至200毫秒）可能会使用柠檬酸铁铵改善肠道与腹腔内脂肪之间的对比度。
