磁共振扩散张量成像在肝脏局灶性病变诊断中的应用

目的：探讨磁共振扩散张量成像（DTI）在肝脏局灶性病变诊断中的价值。方法选取经病理或临床证实的55例患者为研究对象，其中原发性肝癌15例，肝转移瘤7例，肝血管瘤17例，肝囊肿16例。同时，选取20例健康志愿者进行对照。所有受试者均行肝脏常规 MRI 及 DTI 检查，并进行图像后处理，测量平均肝脏表观扩散系数（ADC）值和各向异性分数（FA）值。ADC 和 FA 值均值比较采用两样本 t 检验，P ＜0．05为差异具有统计学意义。结果对照组肝脏平均 ADC 值为（1．513±0．132）×10-3 mm2·s-1、平均 FA 值为0．264±0．064。肝癌组、肝转移瘤组、肝血管瘤组、肝囊肿组、恶性组（包括肝癌组和肝转移瘤组）、良性组（包括肝血管瘤组和肝囊肿组）的 ADC 值分别为（1．395±0．097）×10-3、（1．404±0．034）×10-3、（2．379±0．523）×10-3、（3．645±0．298）×10-3、（1．398±0．081）×10-3和（2．963±0．778）×10-3 mm2· s-1。上述各组的 FA 值分别为0．211±0．031、0．238±0．044、0．258±0．049、0．139±0．045、0．219±0．037和0．203±0．077。肝癌组和肝转移瘤组 ADC 值、FA 值比较差异无统计学意义（P ＝0．816）；肝血管瘤组和肝囊肿组 ADC 值、FA 值比较差异具有统计学意义（P ＜0．001、P ＝0．002）；恶性组 ADC 值比良性组 ADC 值低（P ＜0．001）；恶性组与良性组 FA 值比较差异无统计学意义（P ＝0．469）。结论肝脏 DTI 联合常规磁共振成像序列可获得更加丰富的信息，有助于肝脏局灶性病变的诊断和鉴别诊断。

Application of Diffusion Tensor Magnetic Resonance Imaging in Diagnosis of Focal Hepatic Lesions

Objective To investigate the value of diffusion tensor magnetic resonance imaging （DTI）in the diagnosis of focal hepatic lesions.Methods Both magnetic resonance imaging（MRI） and DTI were performed in 55 patients with pathologically or clinically confirmed hepatic lesions （15 cases of primary hepatic carcinoma,7 cases of hepatic metastasis,17 cases of hepatic hemangi-oma,and 16 cases of hepatic cyst）and 20 healthy subjects.Image post-processing was performed and apparent diffusion coefficient（ADC）maps and fractional anisotropy（FA）maps were genera-ted.The ADC and FA values were compared by using a two-sample t test.P 〈0.05 was consid-ered statistically significant.Results The mean ADC value was （1.513±0.132）× 10 -3 mm2 · s-1 ,（1.395±0.097）× 10-3 mm2 · s-1 ,（1.404±0.034）× 10 -3 mm2 · s-1 ,（2.379 ± 0.523）× 10-3 mm2 ·s-1 ,（3.645±0.298）×10-3 mm2 ·s-1 ,（1.398±0.081）×10-3 mm2 ·s-1 and （2.963±＆amp;nbsp;0.778）× 10-3 mm2 · s-1 in healthy control group,hepatic carcinoma group,hepatic metastasis group,hepatic hemangioma group,hepatic cyst group,malignant group（including hepatic carcino-ma group and hepatic metastasis group）and benign group（including hepatic hemangioma group and hepatic cyst group）,respectively.The mean FA value was 0.264 ± 0.064,0.211 ± 0.031, 0.238±0.044,0.258±0.049,0.139±0.045,0.219±0.037 and 0.203±0.077 in healthy control group,hepatic carcinoma group,hepatic metastasis group,hepatic hemangioma group,hepatic cyst group,malignant group and benign group,respectively.There were no significant differences in ADC and FA values between hepatic carcinoma group and hepatic metastasis group（P =0.816）. However,differences in ADC and FA values were significant between hepatic hemangioma group and hepatic cyst group（P 〈 0.001 and P = 0.002,respectively）.Compared with benign group, ADC value significantly decreased in malignant group（P 〈0.001）.But the difference in FA value was not significant between benign group an