目的：评价使用枸橼酸铁铵后3D-MRU图像改善的情况。材料与方法：我们以相同的采集参数对共计22例病人在服用枸橼酸铁铵前、后分别行3D-MRU成像。图像评价从胃肠信号消除情况和图像改善情况两方面进行。结果：使用造影剂后左、右肾门周围的小肠信号则分别由1.10±1.22和1.28±0.96降至0.62±0.39和0.57±0.32。使用造影剂后，左、右肾门周围小肠信号均有显著性降低（两者的P值均小于0.05）；而左、右两区间的小肠信号降低程度无显著性差异（P>0.05）。MRU的图像质量在造影前后则分别为4.25±1.84，7.75±1.84（P<0.05）。结论：枸橼酸铁铵的使用几乎可完全消除3D-MRU图像中的胃肠信号，明显改善图像质量。

Objective: To evaluate the elimination of the high signals in gastrointestinal tract by using ferric ammonium citrate(FAC) with appropriate time of inversion recovery(TI) in performing 3D-MRU. Materials and Methods: Twenty-two patients were involved in this study. 3D-MRU imaging were performed in all patients both before and after oral FAC administration. Image assessment was based on the extent to which the gastrointestinal signals were eliminated(contrast effect) and to which the image quality was improved(image effect). Results: After administration, the signal intensity of intestines around left renal hilum decreased from primary 1.10±1.22 to 0.62±0.39, while the signal intensity of intestines around right renal hilum was 0.57±0.32 comparing with 1.28±0.96 before FAC administration. The signal intensity of intestines around right(P<0.05) and left renal hilum(P<0.05) decreased significantly after taking FAC. No significant difference was found on signal intensity decrease between intestines around right and left renal hilum(P>0.05). The image quality was significantly elevated from primary 4.25±1.84 to 7.75±1.84 after administration(P<0.05). Conclusions: The combined use of FAC and appropriate TI can suppress gastrointestinal signals effectively and improve image quality significantly in 3D-MRU.