中分化松果体实质瘤影像学表现(附31例报告)

Imaging features of pineal parenchymal tumor of intermediate differentiation:A report of 31 cases

目的观察中分化松果体实质瘤的CT、MRI表现。方法回顾性分析31例经手术和病理证实的中分化松果体实质瘤患者,观察CT、MRI图像上病灶的形态、边界、大小、信号（密度）、强化方式及幕上脑积水情况等。结果 31例中分化松果体实质瘤肿瘤形态多为不规则分叶状（23/31,74.19%）,部分边界不清（18/31,58.06%）,直径以20~50mm居多（27/31,87.10%）。CT均为等密度或稍高密度,部分可见囊变区（23/31,74.19%）及钙化灶（5/20,25.00%）,少数可有出血（4/31,12.90%）。MRI上T1WI以等稍低信号为主（20/29,68.97%）,T2WI上以等稍高信号为主（20/29,68.97%）,部分信号混杂（9/29,31.03%）。病灶多呈不均匀明显强化（20/29,68.97%）,部分可见邻近脑膜强化（17/29,58.62%）。31例患者均有不同程度的幕上脑积水及第3脑室前下疝。结论中分化松果体实质瘤具有一些典型的影像学征象,提高影像学认识有助于术前诊断。

Objective To observe the imaging features of pineal parenchymal tumor of intermediate differentiation（PPTID）.Methods Totally 31 patients with PPTID confirmed by surgery and pathology were analyzed retrospectively.The features on CT/MRI images were observed and analyzed,including the shape,margin,size,signal,dense,enhancing patterns supratentorial hydrocephalus and so on.Results In 31 cases,the shape of most tumors was irregularly lobulated（23/31,74.19%）,the tumor margin was ill defined（18/31,58.06%）and the size was 20 to 50 mm mostly（27/31,87.10%）.On CT images,the tumors were isodense or slightly hyperdense,and cystic formation（23/31,74.19%）and calcification（5/20,25.00%）can be observed in some cases.On MRI images,the lesions show isointense or slightly hypointense on T1WI（20/29,68.97%）,and isointense or slightly hyperintense on T2WI（20/29,68.97%）,homogeneous or heterogeneous.Hemorrhage is rare（4/31,12.90%）.On enhanced TIWI images,the tumor was heterogeneously and apparently enhanced（20/29,68.97%）,and the meninges near the lesion also enhanced in some cases（17/29,58.62%）.Supratentorial hydrocephalus and the third ventricle herniation were found in all cases.Conclusion PPTID shows some characteristic features on CT/MRI imags,which might be helpful for preoperative diagnosis.