磁共振扩散加权与T_2加权成像对肝脏局灶性病变检出的比较研究  

Detection of Focal Liver Lesions:Comparison of MR Diffusion-Weighted and T_2-Weighted Imaging

作　　者：王化[1] 王霄英[2] 黄勇[2] 吴冰[2] 蒋学祥[2] 

机构地区：[1]天津医科大学附属肿瘤医院放射科,天津300060 [2]北京大学第一医院医学影像科

出　　处：《实用放射学杂志》2008年第11期1487-1491,共5页Journal of Practical Radiology

摘　　要：目的比较磁共振扩散加权成像(diffusion-weighted imaging,DWI)与T2加权成像(T2-weighted imaging,T2WI)对肝脏局灶性病变的检出效能。方法选择T2WI与DWI2种序列均进行了检查的57例患者共79个病灶(45个恶性,34个良性)纳入本次研究。2位读片者采用盲法分别阅读T2WI与DWI图像。第3位读片者测量病灶和邻近肝实质在DWI及T2WI上的信号强度,计算病灶/肝信号强度比(contrast ratios,CR)。比较2种序列之间检出率及CR值的差异。结果2种序列对恶性病灶的检出率之间的差异无统计学意义,T2WI对全部病灶和良性病灶的检出率高于DWI(2位读片者P<0.001)。对于恶性病灶,当在一种序列上检出病灶即计为检出时,则T2WI+DWI的检出率高于DWI(读片者1P=0.008,读片者2P<0.001),但与T2WI之间检出率的差异无显著性。共对46个病灶测量了CR。良性病灶的CR值在T2WI高于DWI(P=0.008),恶性病灶和全部病灶的CR值在2种序列之间的差异无统计学意义。结论DWI对恶性病灶的检出效能低于T2WI,对良性病灶的检出效能也不及T2WI。Objective To compare the efficacy of DWI and T2WI in detection of focal liver lesions. Methods Fifty - seven patients with 79 focal hepatic lesions （45 malignant and 34 benign） were included in the study. Both T2WI and DWI were performed on each patient. T2WI and DWI images were interpreted by two radiologists independently. The signal intensity （ SI） of the lesions and adjacent liver parenchyma on T2WI and DWI was measured, and the contrast ratios （ CR, the ratio of SI of lesion/liver） were calculated. The detecting rates of the lesions and the mean CRs were compared between the two sequences. Results There was no significant difference in the detecting rate of malignant lesions by T2WI and DWI. The detecting rates of all lesions and benign lesions by T2WI were higher （ two observers P 〈0. 001 ） than those by DWI. When the two sequences were combined together, the detecting rate by T2WI ＋ DWI was significantly higher （observer 1 P =0. 008, observer 2 P 〈0. 001） than that by DWI alone, however, still not statistically higher than that by T2WI. CR was calculated for 46 lesions. The CRs of benign lesions on T2WI were higher than those on DWI （ P = 0. 008） , and no significant differences were found between the two sequences as for the CRs of malignant and all lesions. Conclusion DWI is not superior to T2WI in detection of malignant lesions, and inferior to T2WI in detection of benign lesions.

关 键 词：肝脏 肝脏局灶性病变 磁共振成像 扩散加权成像 

分 类 号：R575[医药卫生—消化系统] R445.2[医药卫生—内科学]