3.0T磁共振3DF AME动态增强序列对肝脏局灶性病变的诊断价值

目的：探讨3.0T磁共振3D FAME动态增强序列对肝脏局灶性病变的诊断价值。方法：对65例肝脏局灶性病变（原发性肝细胞癌30例,胆管癌4例,转移瘤8例,肝血管瘤12例,肝囊肿11例）相继进行MR常规平扫及3D FAME序列多期动态增强扫描,包括肝动脉期、门静脉期、平衡期及延迟期,观察病灶各期的强化特征,并利用动态强化自动分析软件及时间-信号强度曲线分析各种病变的曲线类型。结果：不同的肝脏局灶性病变具有特征性的强化方式,时间-信号强度曲线较客观反映不同病变的血流动力学特性。肝细胞癌的时间-信号强度曲线分为3种类型：Ⅰ型（速升速降）、Ⅱ型（速升缓降）、Ⅲ型（缓升缓降）,30例肝细胞癌中60.0%（18/30）表现为Ⅰ型曲线类型,26.7%（8/30）表现Ⅱ型曲线类型,13.3%（4/30）表现Ⅲ型曲线类型。肝血管瘤的动态增强曲线分为2种类型：Ⅰ型（缓升平坦型）、Ⅱ型（速升平坦型）,12例血管瘤中66.7%（8/12）表现为Ⅰ型曲线类型,33.3%（4/12）表现Ⅱ型曲线类型。4例胆管癌动态增强曲线为缓慢上升型。转移瘤表现为2种强化方式,2例（25.0%）表现为早期周边环状强化,6例（75.0%）表现为轻度强化。11例肝囊肿增强扫描各期均无强化。结论：3D FAME动态增强序列有助于肝脏局灶性病变的定性诊断。

Application of 3D FAME dynamic contrast-enhanced MRI in the diagnosis of focal hepatic lesions

Objective： To evaluate the diagnostic value of 3.0 Tesla three-dimensional fast acquisition with multiphase enhanced fast GRE（3D FAME）sequence in focal hepatic lesions.Methods： MR imaging was performed on 65 patients with focal hepatic lesions including 30 cases with hepatocellular carcinoma,4 cases with cholangiocarcinoma,8 cases with metastases,12 cases with hamangioma and 11 cases with hepatic cyst.The imaging protocol included conventional plain scan and Gd-enhanced 3D FAME multi-phase dynamic scan（hepatic arterial,portal venous,equilibrium and delayed phases）.Enhancement patterns were observed.The time-singal intensity curve （TIC） was analyzed.Results： There were characteristic enhancement patterns among various types of focal hepatic lesions.The time-singal intensity curve reflected the hemodynamic changes of the lesions.TIC of hepatocellular carcinoma was classified as： type Ⅰ（rapidly increased and decreased）,which was shown in 60.0%（18/30）of cases,type Ⅱ（rapidly increased and slowly decreased）,which was shown in 26.7%（8/30）of cases,and type Ⅲ（slowly increased and decreased）,which was shown in 13.3%（4/30）of cases.TIC of hamangioma was classified as： type Ⅰ（slowly increased and remained fairly constant）,which was shown in 66.7%（8/12）of cases,and type Ⅱ（rapidly increased and remained fairly constant）,which was shown in 33.3%（4/12）of cases.The TIC of cholangiocarcinoma was slowly increased.Among 8 cases with metastases,25.0%（2/8）showed early peripheral-rim enhancement,75.0%（6/8）displayed slight enhancement.Eleven cases with hepatic cyst showed no enhancement.Conclusion： 3D FAME dynamic contrast-enhanced MRI was useful in characterizing and diagnosing various focal hepatic lesions.