3.0T磁共振动态增强技术对肝脏病变的临床诊断价值

Clinical Evaluation of 3.0T Dynamic Contrast Enhanced MRI in Liver Lesion

目的:探讨3.0T磁共振动态增强扫描对肝脏病变的鉴别诊断价值及不同病变的强化特征。方法:收集39例肝脏占位患者,所有病例经手术病理证实,包括原发性肝癌12例、肝脏转移瘤4例、肝脏血管瘤8例、肝脏腺瘤4例、局灶性结节增生3例、肝脓肿2例,术前分别行磁共振常规扫描、动态增强扫描及延迟扫描;对动态增强图像绘制感兴趣区,绘制时间-信号强度曲线(time-signal curse,TSC)。结果:12例原发性肝癌的病变周边见"假包膜";6例巨块型肝癌可见中央坏死及出血;2例病灶可见病灶中脂肪变性,动态增强曲线呈现出"快进快出";肝脏转移瘤4例,病变中央大都为坏死区,可见包膜影,增强包膜早期强化,强化方式为"快进快出";肝脏血管瘤8例在常规T2WI脂肪抑制呈明显的高信号,边界清楚,动态增强曲线为"慢进慢出型";肝脏局灶性结节2例,边缘尚清,病灶中央可见纤维瘢痕,增强方式为"快增缓增型";肝脏腺瘤4例,边缘清楚,动态增强早期明显强化;肝脓肿2例,病灶分布在肝周缘,边界清楚,增强扫描病灶周边强化。结论:3.0T磁共振动态增强扫描具有极高的时间分辨率,结合常规序列对肝脏占位的鉴别诊断具有重要意义。

Objective To evaluate the diagnostic value of different enhancement character shown on 3.0T dynamic contrast enhance magnetic resonance imaging（DCE-MRI） in hepatic lesion.Methods Thirty-nine patients with hepatic occupying lesion were diagnosed with surgical pathological specimens,including primary hepatic carcinoma（n=12）,hepatic metastatic tumor（n=4）,hepatic angioma（n=8）,hepatic adenoma（n=4）,focal nodular hyperplasia,and hepatic abscess（n=2）.All patients underwent conventional MR imaging,DCE-MR imaging and delay phase of CE-MR imaging.Regions of interest were drawn on DCE-MR images and time-signal curses were plotted.Results For primary hepatic carcinoma,pseudo-capsules were seen around lesions in all 12 patients,adipose degenerations were observed in 2 patients,central necrosis and hemorrhages were found in 6 patient with massive hepatic carcinoma,the time-signal curve appeared as the type of ＇rapidly increased then rapidly decreased＇;For hepatic angioma,lesions appeared significant hyperintensity on fat saturated conventional T2WI images,the time-signal curve appeared as the type of ＇slowly increased then slowly decreased＇;For hepatic metastatic tumor,most lesions had central necrosis and early enhanced capsules,the time-signal curve appeared as the type of ＇rapidly increased then rapidly decreased＇.For focal nodal hyperplasia,central scars were detected,the time-signal curve appeared as the type ＇rapidly increased then slowly increased＇.For hepatic adenoma,clear lesions enhanced significantly in the early phase of DCE-MRI.For hepatic abscess,lesions were detected on the periphery of liver,and enhanced peripherally on DCE-MRI.Conclusion 3.0T DCE-MRI has high temporal resolution,may play an important role in diagnosis of hepatic occupying lesion when combined with conventional MRI sequences.