儿童朗格汉斯组织细胞增生症肝脏浸润的CT及MRI征象分析

The CT and MRI Analyzing of Liver Involvement in Children Langerhans’ Cell Histiocytosis

目的提高对儿童朗格汉斯组织细胞增生症(LCH)肝脏浸润的CT及MRI表现的认识。方法搜集33例经组织学证实为LCH,同时上腹部CT和MRI表现肝脏病变的患儿,观察CT和MRI的肝脏大小,Glisson鞘改变、肝实质及其病灶的表现特点。统计各种征象出现的例数和百分比,分析Glisson鞘改变及肝实质病变类型之间的关系。结果(1)肝脏间质改变:Glission鞘增宽31例,表现为沿门静脉、胆管周围结构不同程度增宽,平扫呈低密度/T1WI低信号、T2WI略高信号,增强呈轨道状延迟强化,边缘模糊(晕征),或强化不明显,边缘清楚,Glission鞘与肝组织交接面呈颗粒状或锯齿状。(2)肝实质改变:肝脏密度/信号较均匀5例,无结节,增强扫描均匀强化;肝脏质地增粗9例,增强动脉期均呈不均质强化,静脉期、延迟期密度均匀;肝脏弥漫性小结节(<3 mm)9例,沿Glission鞘分布为主,呈近似圆形低密度区/T1WI低信号、T2WI高信号,DWI高信号,增强扫描结节状或环状强化;肝脏弥漫性或节段性分布较大结节(>3 mm)10例,结节呈等密度/T1WI等或高信号、T2WI稍低信号,强化不明显,其周围肝组织呈网格状强化。(3)其他:脾脏肿大29例,侧支循环形成2例,肝门、肠系膜淋巴结肿大1例。Glission鞘改变与肝内病变关系为:Glission鞘强化、边缘模糊,肝脏内病变为较均质、多发性小结节,同时有强化;Glission鞘强化、边缘清楚,则肝脏内病变为无强化的大结节。结论儿童LCH肝脏浸润CT、MRI具有特征性表现,主要为Glission鞘增宽,边缘不规则,伴有实质密度/信号异常、颗粒状、小结节状和较大结节状表现,肝、脾肿大;Glission鞘结合肝实质的表现类型对区分病变的不同时期具有帮助。

Objective To improve the recognition CT and MRI manifestations of liver involvement in children with langerhans’cell histiocytosis(LCH).Methods Thirty-three children with histopathologically confirmed LCH displayed liver involvement on abdominal CT and MRI.The CT and MRI manifestations included hepatomegaly,Glisson capsule abnormality,and liver parenchymal disease.The number and percentage of different manifestations were evaluated,and the relation of diseases types between Glisson capsule abnormality and liver parenchymal disease were analyzed.Results(1)Hepatic interstitial changes:31 cases of Glisson capsule expanded,manifested as different degrees of dilatation along the portal vein and surrounding structures of the bile duct.The plain scan showed low density/T1 WI low signal,slightly higher T2 WI signal,and the enhancement showed delayed rim enhancement,The edge is ill-defined(halo sign),or the enhancement not obvious,the edge is distinct,the interface between Glisson capsule and the liver tissue is granular or jagged.(2)Liver parenchymal changes:5 cases had relatively uniform liver density/signal,no nodules,uniform enhancement.9 cases had coarse liver texture,heterogeneous enhancement in the arterial phase of enhancement,uniform density in the venous phase and delayed phase.Nine cases of diffuse small nodules(<3 mm)in the liver,mainly distributed along the Glisson capsule,appearing as approximately round low-density areas/T1 WI low signal,high T2 WI signal,high DWI signal,nodular or ring-like enhancement.There were 10 cases of diffuse or segmental large nodules(>3 mm)in the liver.The nodules were iso-density or high T1 WI signal,slightly low T2 WI signal,and the enhancement was not obvious.The surround-ing liver tissue showed grid-like enhancement.(3)Others:29 cases of splenomegaly,2 cases of collateral circulation,1 case of hepatic hilar and mesenteric lymphadenopathy.The relationship between the changes of Glisson capsule and intrahepatic lesions was Glisson capsule enhances and the edges were ill-defined.The lesions in the liver are relatively homogeneous with multiple nodules,and there was enhancement.If the Glisson capsule enhances and the edges are clear,the liver lesions unenhancing large nodules.Conclusion CT and MRI manifestations of children langerhans’cell histiocytosis had characteristics that displayed Glisson capsule expansion with irregular margin,liver parenchymal disease with granular texture,multiple small nodes or large nodes.Glisson capsule characteristics combined with liver parenchyma’s diseases types could suggest stage of disease change.