睾丸表皮样囊肿的CT及MRI表现

CT and MRI features of testicular epidermoid cyst

目的:探讨睾丸表皮样囊肿(TEC)的CT、MRI表现,提高该疾病认识。方法:回顾性分析16例经我院外科手术病理证实的TEC术前CT和MRI资料。11例接受睾丸MRI平扫,其中1例同时接受睾丸MRI增强检查。5例接受CT检查,其中4例同时接受睾丸增强CT检查。总结TEC的CT、MRI影像表现。结果:肿瘤均为单发肿瘤,位于左侧睾丸者9例,位于右侧睾丸者7例。15个病灶呈类圆形或类椭圆形,1个病灶形态不整。所有病灶边界清晰。病灶平均最大径为(2.28±1.72)cm。11例接受MRI检查中,T_1WI上6个病灶呈不均匀的稍低信号或稍高信号,5个病灶呈均匀稍低或低信号,其中2个病灶中心局限性高信号,呈"靶征";T_2WI上10个病灶呈不均匀的稍高或高信号,1个病灶呈均匀的高信号,11个病灶均见T_2WI低信号环影。5例行CT检查中,2例呈均匀稍低密度,2例呈均匀低密度,1例整个病灶呈结节样钙化密度改变。3例合并钙化,其中1例病灶壁见环形钙化,1例病灶较大,内见多发条片状及点状钙化。5例增强检查(1例增强MRI,4例增强CT)病灶中心未见强化,病灶壁见轻度强化。结论:TEC表现为单侧睾丸的类圆形或椭圆形囊性病灶,CT上表现为低或稍低密度病灶,可合并钙化灶;MRI T1WI表现为均匀或不均匀稍低或低信号,T2WI表现为稍高或高信号,几乎所有病灶均见低信号纤维环,结合典型影像表现有助于明确诊断。

Objective： To investigate CT and MRI features of testicular epidermoid cyst （TEC） and increase understanding of the disease. Methods： Preoperative CT and MRI data of 16 pathologically proved TEC were analyzed retrospectively. Eleven cases underwent MRI scan and one of them also underwent enhanced MRI. Five cases underwent CT examination and four of them also underwent enhanced CT scan as well. Summarize, the CT and MRI features of TEC. Results： According to the images, all cases showed single lesion, in which 9 were located in the left testicle and 7 in the right. Fifteen lesions were round or oval and 1 lesion was irregular. All lesions were well-marginated, with an average maximum diameter of （2.28±1.72） cm. Among the 11 cases underwent MRI, 6 showed unevenly slightly low or high signal, 5 lesions showed evenly slight- ly low or low signal and 2 showed regionally high signal in the lesion center, called ＂target sign＂, on T^WI. Ten showed un- evenly slightly high or high signal, 1 showed unevenly high signal and 11 showed low signal ring on T2WI. Among the 5 cases undergoing CT, 2 showed evenly slightly low density, 2 showed evenly low density and 1 showed nodular calcification. In the 3 cases with calcification, 1 showed annular calcified in the wall and 1 showed a large lesion with striped and punc- tate calcification. The 5 cases undergoing enhanced examination （both MRI and CT） showed slight enhancement in the wall without enhancement in the center. Conclusion： TEC is characterized by unilateral round or oval cystic lesion in testicle, which shows low or slightly low density with calcification on CT, evenly or unevenly low or slightly low signal on TIWI and high or slightly high signal on TeWI with almost all the lesion showing low signal ring.