成人幕上原始神经外胚层肿瘤的MRI表现

目的:探讨成人幕上原始神经外胚层肿瘤(PNET)的MRI表现,提高对本病的诊断水平。方法:回顾分析10例经手术和病理证实的幕上PNET的MRI资料(其中3例为术后复发而再次手术的病例)。结果:病灶多数位于额叶及额顶叶,病灶普遍较大,病灶绝大多数信号不均匀,病灶内可见囊变/坏死(9例)、出血(3例)、钙化(2例)、流空小血管影(5例),增强后病灶呈明显不均匀强化(9例),2例显示肿瘤脑脊液通路播散,1例显示肿瘤侵犯上矢状窦和颅骨。结论:PNET的MRI表现无特异性,一些MR特征对本病的诊断有一定的帮助,最后的确诊依赖于病理学诊断。

MR imaging findings of supratentorial primitive neuroectodermal tumour in adults

Objective:To study the MR imaging features of supratentorial primitive neuroectodermal tumour(PNET) in adults and improve the understanding of the disease.Methods:MR imagings in 10 patients(3 of them were recurrent tumors after operations) with supratentorial PNETs proved by operation and pathology were analyzed retrospectively.Results:The tumours were mostly located in the frontal and occipital lobes and seen as rather large,heterogeneous masses with cystic and necrotic areas,intratumoral haemorrhage,focal calcification and intratumoral vessels.After contrast administration,the tumours mostly showed marked inhomogeneous enhancement,2 of the 10 patients showed dissemination along cerebrospinal fluid pathways and 1 tumour showed invasion of superior sagittal sinus and cranial bone.Conclusion:MR imaging findings of PNET are non-specific,but some features are helpful in the diagnosis of the disease.The final diagnosis are still based on the pathologic findings.