幕上原始神经外胚层肿瘤的影像学诊断

目的探讨幕上原始神经外胚层肿瘤的影像表现及鉴别诊断。材料和方法回顾性分析15例经病理证实的幕上原始神经外胚层肿瘤CT及MRI表现。结果 15例患者中,12例行MRI平扫加增强,5例行CT平扫加增强,2例均行CT和MRI检查;12例为单发病灶,3例多发病灶。12例单发病灶中,6例为实性肿块型,6例为囊实性肿块型,实性成分CT平扫为等或稍高密度,T1WI等或稍低信号、T2WI等或稍高信号、T2FLAIR等或稍高信号,囊性部分T1WI及T2FLAIR低信号、T2WI高信号,边界清晰,与脑实质分界清楚,瘤周水肿轻或无,瘤内可伴有不同程度囊变坏死、出血或钙化;增强扫描呈轻中度或明显均匀或不均匀两种强化,瘤内或瘤周可见强化血管影;3例多发病灶均表现为实性肿块型,密度及信号类似于单发病灶实性肿块型,增强扫描多发病灶强化不一致,颅内病灶明显均匀强化,颅外椎体或椎管内病灶轻中度均匀强化。结论幕上原始神经外胚层肿瘤影像学表现多样,但有一定特异性,确诊有赖病理及免疫组织化学证实。

Imaging Diagnosis of Supertentorial Primitive Neuroectodemal Tumors

Objective To explore imaging appearance and differential diagnosis of supertentorial primitive neuroectodemal tumors. Materials and Methods CT and MRI manifestations of fifteen cases with supertentorial primitive neuroectodemal tumors confirmed by pathology were analyzed retrospectively. Results In the 15 cases, 12 underwent MRI plain scan and enhancement and 3 CT plain and enhancement, 12 cases were solitary lesion, and 3 were multiple lesions. In the 12 cases with single lesion, 6 were solid mass and 6 were cystic and solid mass.The solid components showed iso-intensity or slightly high intensity on CT scan, while they were iso-/slightly hypo-intensity signal on TIWI, iso-/ slightly hyper-intensity on T2WI and T2FLAIR. The cystic components showed hypo- intensity signal oil T1WI and T2FLAIR, iso-/slightly hyper-intensity on T2WI. The 12 cases appeared clear margin with brain parenchyma and light peritumoral edema, hemorrhage and calcification can be seen in the tumor, which showed mild to moderate or obvious enhancement on enhanced scanning, homogeneously or inhomogeneously. 3 cases of multiple lesions showed solid mass, and their density and signal were similar to a single solid mass. Multiple lesions enhanced inconsistently, intracranial lesions were obvious homogeneous enhancement while extracranial vertebral or spinal lesions were mild to moderate homogeneous enhancement. Conclusion Imaging findings of supratentorial primitive neural ectoderm tumor are diversitic, but have some specificity, confirmed by pathology and immunohistochemistry.