胼胝体发育不全合并脂肪瘤的CT和MRI诊断

Study on CT and MRI diagnosis of dysplasia of corpus callosum (DCC) complicating lipoma

目的探讨胼胝体发育不全合并脂肪瘤的CT和MRI征象,以提高对本病的认识。方法回顾性分析胼胝体发育不全合并脂肪瘤30例的临床、CT及MRI表现。结果胼胝体发育不全CT及MRI表现为双侧脑室体部平直、分离,纵裂池增宽间距加大18例,正常弧线消失12例;第三脑室扩大上移至侧脑室之间20例,上抬至大脑纵裂10例,侧脑室三角区与后角明显扩大6例,轻度扩大12例;MRI矢状位示胼胝体体积缩小,发育不全或缺如。合并脂肪瘤CT表现为侧脑室间条带状低密度(CT值-43Hu～-80Hu),边缘见对称性弧形钙化10例,MRI表现为短T1中长T2和高质子密度信号,在各序列上均与脂肪组织信号同步。结论本病在CT和MRI上具有特征性表现,CT与MRI相结合可提高诊断准确率;MRI具有多维成像能力,优于CT检查。

Objective To study CT and MRI features of dysplasia of corpus callosum（DCC） complicating lipoma and to improve the knowledgement of it. Methods 30 cases with DCC complicating lipoma were included in the study. The CT and MRI appearances of it were evaluated retrospectively. Results The CT and MRI appearances were flattened and separated bodies of both lateral ventricles, enlarged cerebral longitudinal fissure in 18 patients, disappearance of normal curvature in 12 cases. The third ventricle was dilated and clevated into the lateral ventricles in 20 cases and into the cerebral longitudinal fissure in 10 cases. There were obviously enlarged triangular region and back hems of both lateral ventricles in 6 cases, slightly enlarged ones in 12 cases. MRI demonstrated reduction, dysplasia and absence of corpus callosum. The CT appearances were low density foci （CT value from -43Hu to - 80Hu） and symmetrical curved calcification in the edges of lateral ventricles in 10 cases complicating with lipoma. The MRI findings showed high signal on T1WI, mediate on T2WI and high proton density signal. They were consistent with fat tissue on each MRI sequence. Conclusion Although CT and MRI both have characteristic images in for diagnosing DCC complicating lipema, CT combining with MRI can improve the diagnostic rate, and MRI with multiple dimensional imaging is superior to CT in the diagnosis of this kind of disease .