摘要
目的探讨鞍区毛细胞型星形细胞瘤的CT和MR I表现并分析误诊原因。资料与方法回顾性分析12例经病理证实的鞍区毛细胞型星形细胞瘤的影像学表现。11例行头颅MR I平扫及增强扫描,其中4例同时行头颅CT平扫及增强扫描;另有1例仅行头颅CT平扫及增强扫描。结果 12例中囊实性7例,实性5例。8例肿瘤边界不清,4例边界清晰。MR T2W I呈混杂或均匀高信号,T1W I呈等低信号;CT表现为不均匀高密度或等密度;增强扫描多表现为明显不均匀强化。7例视交叉显示不清,3例垂体柄显示不清。术前影像学诊断错误8例,误诊为颅咽管瘤（n=6）、脑膜瘤（n=1）、生殖细胞瘤（n=1）,另有2例未做出明确诊断。结论鞍区毛细胞型星形细胞瘤多为囊实性或实性且有类似Ⅲ~Ⅳ级胶质瘤影像表现的特点,可根据这些特点与其他鞍区肿瘤相鉴别,减少误诊。
Objective To illustrate the CT and MRI features of pilocytic astrocytoma（PA） in sellar region and to analyze the reasons of misdiagnosis.Materials and Methods The imaging findings of twelve patients with the tumor locating in the sellar region histologically proven to be PA were retrospectively analyzed.Eleven patients received plain and enhanced MRI examination,and mainwhile four of them underwent plain and enhanced CT scan.Only one patient was just tested by plain and enhanced CT scan.Results Among twelve cases,seven were solid-cystic and five were solid.Eight of twelve cases shown ill-defined margins.The tumor appeared heterogeneous or homogeneous hyperintense on T2WI,and isointense or hypointense on T1WI.The CT density of the tumor was either inhomogeneous hypodense or isodense.Most of the cases presented intensely inhomogeneous enhancement.The optic chiasma was blurred in 7 cases,and the stalk of pituitary was obscured in 3 cases.Imaging misdiagnosis was made in 8 cases,including craniopharyngioma（n=6）,meningoma（n=1） and germinoma（n=1）.Moreover,indefinite diagnosis was made in 2 cases.Conclusion The common appearance of PA in sellar region is solid mass with cysts or not,and often mimic glioma on grade Ⅲ to Ⅳ,which might be helpful for making the differential diagnosis and reducing misdiagnosis.
出处
《临床放射学杂志》
CSCD
北大核心
2011年第5期621-624,共4页
Journal of Clinical Radiology
