3T MR扩散加权成像对肝脏转移瘤的诊断价值初探

Discussing of the Value of DWI in Hepatic Metastases Diagnosed at 3T

目的:探讨MR扩散加权成像(DWI)对肝脏转移瘤的诊断价值。方法:对临床确诊的25例肝脏转移瘤患者进行DWI、T2WI及Gd-DTPA-T1WI扫描,观察肝脏转移瘤的信号特征,并统计分析3种序列所检出的转移瘤数目。结果:对于直径大于1.0cm的32个转移瘤灶,3种序列都准确检出;而直径小于1.0cm的微小转移瘤,在T2WI上共检出76个,病灶信号均为略高信号;在DWI上共检出85个,呈高信号;在增强门脉期T1WI上共检出68个,大部分瘤灶呈环状强化或不均匀强化。3种序列对转移瘤的检出差别无显著性意义。结论:DWI对肝脏微小转移瘤的敏感性较高,将DW与T2W、GD-DTPA-T1W3种序列相结合,可以互相弥补各序列不足之处,将大大提高肝脏微小转移瘤灶的检出率。

Objective： To discuss the value of DWI in diagnosing hepatic metastases. Methods： DWI, T2WI and Gd DTPA enhanced MR imaging were performed in 25 patients with hepatic metastases. The numbers of detected lesions in each imaging set were statistically calculated,and the characters were observed. Results： Total 32 lesions which diameters larger than 1.0cm were all detected in each imaging set. In the lesions that smaller than 1.0cm, 76 nodules were detected in T2WI with slightly high signal intensity,85 nodules were detected in DWI with high signal intensity,68 nodules were detected in portal venous phase Gd-DTPA-enhanced MR imaging. Most of them were peripheral enhanced or inhomogeneous enhanced. There is no significant difference of each imaging set in the detection of hepatic metastases nodules. Conclusion： The sensitivity of DWI in detecting small hepatic metastases nodules is higher than the other imaging sets. Combined DWI with T2WI and Gd-DTPA-enhanced MR imaging can improve the ratio in the detection of small hepatic metastases,and at the same time,redeem the disadvantage of each other.