磁共振扩散加权成像在肝脏占位病变中的应用

目的探讨磁共振（MR）扩散加权成像（DWI）在肝脏占位病变诊断和鉴别诊断中的应用价值。方法对40例常规磁共振成像（MRI）检查发现有肝脏占位病变患者，进行MRDWI，分析影像特点并测量表面扩散系数（ADC值）。结果40例肝脏占位病变DWI检出75处异常信号病灶。信号特征与病变结构、成分有关。但无一定特异性。病变的ADC值均值为：肝细胞癌（1．25±0．30）×10^-3mm^2／s，肝转移癌（1．12±0．52）×10^-3mm^2／s，肝血管瘤（2．27±0．49）×10^-3mm^2／s，肝囊肿（3．05±0．59）×10^-3mm^2／s，肝脓肿（1．91±0．46）×10^-3mm^2／s，各种病变间ADC值比较均有统计学意义（P〈0．05）。结论与常规MRI相比，DWI病变检出率不低于常规MRI，但各种病变间信号强度无明显特异性。ADC值测量对肝脏占位性病变的诊断和鉴别诊断。特别是对良恶性病变的鉴别有重要参考价值。

Application of Magnetic Resonance Diffusion Weighted Imaging for Detecting Focal Liver Lesions

Objective To study the value of diffusion weighted imaging （DWI） in diagnosis and identify of focal liver lesions. Methods DWI was performed in 40 patients with liver lesions detecting by routine MRI. The imaging character and apparent diffusion coefficient （ADC value） were analyzed. Results 75 lesions were detected in these 40 patients. The signal feature was related to the structure and composition of the lesions, but that had no specificity. The average ADC value of hepatocellular carcinoma was （1.25±0.30）×10^-3mm^2/s, liver metastases （1.12±0.52） ×10^-3mm^2/s, hepatic bemangiomas （2.27±0.49）×10^-3mm^2/s, hepatic cysts （3.05±0.50） ×10^-3mm^2/s, and hepatapostema （1.9±0.46）×10^-3mm^2/s. The difference between the average ADC values was significant （P〈0.05）. Conclusions DWI has advantages for detecting focal liver lesions. The measurement of ADC value was helpful in diagnosis and identification of focal liver lesions, especially in differentiation of benign and malignant lesions.