肝脏血管平滑肌脂肪瘤的影像学及病理学分析

目的:分析肝脏血管平滑肌脂肪瘤的CT及MR I的影像学特点与病理基础,减少对该肿瘤的误诊。方法:回顾性分析10例肝血管平滑肌脂肪瘤患者的CT及MR I影像学表现,并与病理组织学对照分析。结果:在10例肝脏血管平滑肌脂肪瘤中,脂瘤型3例,血管瘤型1例,肌瘤型1例,混合型5例。脂瘤型以脂肪成分为主,CT、MR I显示脂肪密度或信号。血管瘤型以血管成分为主,CT、MR I增强可见动脉期明显强化,门静脉期密度或信号仍高于同期肝实质。肌瘤型主要是由平滑肌成分为主,脂肪成分很少。混合型3种成分含量相似,平扫CT为较均匀低密度,MR I T 1W呈低信号,T 2W呈稍高信号;增强扫描CT、MR I均呈动脉期明显强化,门静脉期仍有强化。结论:不同病理组织学类型的肝脏血管平滑肌脂肪瘤,CT和MR I表现有所不同,这取决于肿瘤所含的主要组织学成分。

Correlation between pathology and imaging characteristics of hepatic agiomyolipoma

Objective: To discuss CT and MRI characteristics of hepatic angiomyolipoma based on pathological findings.Methods: The CT and MRI appearances with related pathohistological subtypes of 11 hepatic angiomyolipomas from 10 patients were retrospectively analyzed.Results: Ten patients with hepatic angiomyolipomas were subcategorized into lipomatous(3 cases),angiomatous(1 case),myomatous(1 case) and mixed(5 cases) subtypes.Lesions of the lipomatous type were mainly composed of adipocytes which could be easily recognized on both CT and MRI.Abnormal vessels were commonly seen in the angiomatous lesions,which showed pronounced enhancement in the early arterial phase and remained higher than or isodense with the normal parenchyma in the portal phase.The myomatous type was predominantly composed of leiomyoid cells mixed with small amount of adipocytes.The mixed type was the most frequent,evenly comprising sheets of epithelioid muscle cells admixed with islands of adipocytes and abnormal vessels,and showing homogeneously low density on plain CT and low signal intensity on T1-weighted,intermediately high signal intensity on T2-weighted MRI scans.On dynamic study with both CT and MRI,the mixed type exhibited obvious enhancement,which retained to some degree during the portal phase.Conclusion: The discrete CT and MRI appearances of hepatic angiomyolipomas with different pathological subtypes depend on the components of the tumor.