MR全肝灌注成像在直肠癌肝转移中应用的初步探讨

Preliminary Study of MR Whole Liver Perfusion Weighted Imaging in the Detection of Liver Metastases of Rectal Carcinoma

目的:探讨MR全肝灌注检查对直肠癌肝转移的临床应用价值。方法:选择46例直肠癌患者(16例肝转移,30例无肝转移)行MR全肝灌注扫描,采用三维容积内插序列(3D-VIBE),对比剂按注射流率4ml/s,扫描时平静呼吸,连续扫描90s,每3s进行一次全肝采集。在工作站上获取腹腔干水平腹主动脉、门静脉主干、肝实质和脾脏的时间-信号强度曲线(TIC),计算肝实质的相对肝动脉灌注量(HAP)、相对门静脉灌注量(HPP)及肝动脉灌注指数(HPI),并对有或无肝转移组的上述指标进行统计分析。结果:肝转移组HPI(平均0.387)高于无肝转移组(平均0.285),而肝转移组相对HPP值(平均0.967)低于无肝转移组(平均为1.332),其中HPI和HPP在两组间差异有统计学意义(P<0.05),而肝转移组的相对HAP值(平均0.565)高于无肝转移组(平均0.535),但在两组间差异无统计学意义(P>0.05)。结论:MR全肝灌注检查技术可分析肝内血流灌注的改变,对预测直肠癌肝转移有重要潜在应用价值。

Objective： To investigate the clinical value of MR whole liver perfusion weighted imaging （PWI） in the depiction of liver metastases in patients with rectal carcinoma. Methods：Forty-six patients with rectal carcinoma were divided into 2 groups,f16 patients with liver metastases （MG） and 30 patients without （NMG）] ,all of them underwent MR whole liver PWI,3D volume interpolated breath-hold sequence （3D VIBE） was used,which were performed every 3s continuously for 90s during the injection of contrast medium at the rate of 4ml/s with the patient breathed gentIy. Time signal intensity curve （TIC） of aorta at the level of celiac artery trunk,main trunk of portal vein,liver and spleen were obtained at worksta- tion. The values of relative hepatic arterial perfusion （HAP）, hepatic portal vein perfusion （HPP）,and hepatic perfusion index （HPI） with liver parenchyma were calculated and these values of the 2 groups （MG/NMG） were analyzed. Results：Relative HPI of MG （mean=0. 387） was higher than that of NMG （m：0. 285） ,while the value of relative HPP of MG （m= 0. 967） was lower than that of NMG （m： 1. 332） ,showing significant statistical differences （P〈0.05）. The relative HAP of MG （m=0. 565 vs 0. 535） was higher than that of NMG （m=0. 535）,with no statistical difference （P〉0.05）. Conclusion：Intra-hepatic hemodynamic changes could be depicted by MR whole liver PWI,which might have potential significance for the early detection of liver metastases.