淋巴管瘤的磁共振成像诊断

MRI Diagnosis of Lymphangioma

目的:探讨淋巴管瘤不同病理学类型的磁共振表现特点以及鉴别诊断。方法:回顾性分析44例经手术病理证实为淋巴管瘤的MRI检查资料,所有病例均行矢、冠、轴三平面扫描,其中30例于MRI平扫后行常规增强扫描。以病理学所见为参照,分析各病理类型淋巴管瘤的MRI表现特点并统计分析不同病理类型淋巴管瘤发生部位的差异。MRI征象分析包括:病变的形态、累及范围、有无包绕血管、内部信号特点、有无分房、分隔厚薄情况及强化特征。结果:MRI上淋巴管瘤的形态多为不规则状(38/44),边界不清(30/44),部分见血管包绕征(17/44),较大者产生占位效应。不同病理类型的淋巴管瘤发生部位的差异无显著性。与邻近肌肉组织相比,24个(54.5%)病变表现为T1WI上等或高信号、T2WI上更高信号区,较具特征。囊状淋巴管瘤31例,病变内可见液-液平面,分房大,分隔细、薄,增强扫描呈轻度或无强化;海绵状淋巴管瘤7例,表现为分房多,大小不一,分隔厚或有乳头状突起,增强扫描显示分隔及乳头明显强化;血管淋巴管瘤6例,MR表现为分房大小不一,分隔厚薄不一,内未见液-液平面,增强扫描囊壁及分隔明显强化,难与海绵状淋巴管瘤鉴别。结论:淋巴管瘤不同病理学类型的MRI表现有一定特点,MRI对于鉴别囊状淋巴管瘤与其他两类较具价值,而海绵状淋巴管瘤有时难以与血管淋巴管瘤鉴别。

Purpose： To investigate the characteristics and differential diagnosis of different pathologic types of lymphangioma on MRI.Methods： The MRI images of lymphangioma in 44 patients confirmed by pathology were analyzed retrospectively.All lesions were scanned in transverse,coronary and sagital plan,30 patients were performed contrast enhancement MRI after plain scan.Compared with the corresponding histopathologic findings,the appearances of MRI of different pathologic types of lymphangioma were analyzed.The distribution differences of the different pathologic types of lymphangioma were analyzed.The features analyzed on MR images included the shape and extent of the lesions,the encasement of vessels,the signal intensity in lesions,unilocular or multilocular,the thickness of the septa and the characteristics of contrast enhancement.Results：On MR images,the lymphanigoma appeared as irregular（38/44）,ill-defined（30/44）,and vessel encasement signs（17/44） in lesions.Some large lesions produced space-occupying effect.There was no statistic difference in the distribution of the different pathologic types of lymphangioma.Compared with the adjacent muscles,24（54.5%）lesions appeared as isointenstiy or hyperintensity（24/44） on T1WI and more distinct hyperintensity on T2WI.Thirty-one lesions were confirmed as cystic lymphangioma pathologically which demonstrated cystic nature：with thin or fine septa and fluid-fluid level in some lesions,nonenhancing or mild cystic or septal enhancemen after IV contrast administration.Seven cases were cavernous lymphangioma which appeared as multilocular of different size with thick septa or papillar convex that appeared as distinct enhancement.Six cases were hemolymphangioma which appeared as multiple septations of varying thickness,none of them demonstrated fluid-fluid levels.After IV contrast administration,the cystic wall and the septa showed distinct enhancement.Sometimes,it was difficult to differentiate the hemolymphagioma from the cavernous lymphangioma.Conclusions：There are characteristic MRI features in different pathologic types of lymphangioma.MRI is a valuable method to differentiate the cavernous lymphangioma and hemolymphangioma from the cystic lymphangioma.However,it might be difficult to differentiate the cavernous lymphagioma from the hemolymphangioma.