多层动态增强MRI技术对肝血管瘤诊断的评价

目的:研究射频毁坏傅立叶采集稳态技术(RFFAST)的动态增强及延迟增强扫描MRI对肝血管瘤的诊断价值。方法:34例肝血管瘤患者行常规MRT1WI和T2WI横断面扫描。经肘静脉团注GdDTPA0.1mmol/kg,后推入10ml生理盐水冲洗(推入时间5～6s),再行射频毁坏傅立叶采集稳态技术T1WI动态增强扫描及延迟增强扫描,分析病灶及邻近肝实质增强。结果:共发现肝血管瘤病灶67个,T1WI上呈低信号,T2WI上呈高信号;动态增强显示46个病灶呈边缘不连续的结节样强化,21个病灶呈周边不规则强化或迅速强化充填;5个病灶动态增强早期见引流静脉较早强化,14个瘤周肝实质强化。结论:磁共振成像检查中,射频毁坏傅立叶采集稳态技术T1WI动态增强扫描能够显示肝血管瘤及邻近实质强化方式,与其他成像序列结合更有利于肝血管瘤的诊断。

Role of Dynamic Enhanced MR Imaging in the Diagnosis of Hepatic Hemangioma

Objective:To study the value of dynamic enhanced MR imaging with RF FAST T_1WI in the diagnosis of hepatic hemangioma. Methods:Axial unenhanced T_1WI and T_2WI were obtained in 34 cases of hepatic hemangioma.Then,dynamic enhanced RF FAST T_1WI were obtained immediately after the manual injection of a bolus of 0.1mmol/kg of Gd-DTPA into the antecubital vein followed by a 10ml flush with normal saline.Enhancing pattern of each hemangioma and adjacent hepatic parenchyma was analyzed.Results:A total of 67 hepatic hemangiomas were found,and low and high signal intensity of the lesions were seen on T_1WI and T_2WI,respectively.On dynamic enhanced MR imaging,46 of the 67 hemangiomas had peripheral discontinuous nodular enhancement on the early phase images with progressive and centripetal enhancement,and the rest had irregular peripheral enhancement or rapidly filling enhancement.Large enhanced draining veins were found in 5 hemangiomas.Enhancement of adjacent hepatic parenchyma were seen in 14 hemangiomas.Conclusion:Dynamic contrast-enhanced RF FAST T_1WI can display the enhancing pattern of hepatic hemangioma and the adjacent hepatic tissue.Combined with other scanning sequences,it will add to the confidence of the diagnosis of hepatic hemangioma.