摘要目的：探讨成人颅脑毛细胞型星形细胞瘤（PA）的影像表现特征。方法回顾性分析经手术病理证实的32例成人PA的影像及病理资料。男13例，女19例；年龄20～68岁，中位年龄30岁。结合文献分析其MRI特征。结果31例单发，1例多发，共33个病灶，其中小脑13个、幕上脑叶12个、侧脑室5个、四脑室2个、鞍区1个。MRI表现分为5种类型：混杂信号肿块型11个，T2WI及增强扫描呈混杂信号肿块；强化囊壁伴强化结节型8个，T2WI呈囊伴壁结节，增强扫描囊壁及壁结节均有强化；不强化囊壁伴强化结节型7个，增强扫描囊壁未见强化；假囊型5个，T2WI呈单房或多房囊性，增强扫描囊壁强化或者部分强化；实性肿块型2个，T1WI及T2WI呈实性肿块，增强扫描不均匀强化。29个病灶周围无水肿或仅轻度水肿，4个灶周水肿显著；4个病灶伴钙化；12个病灶伴出血。结论成人颅脑PA的MRI表现具有一定的特征性。

abstractsObjective To analyze and summarize MRI findings of brain pilocytic astrocytoma in adults. Methods Thirty-two cases (13 males and 19 females) of brain pilocytic astrocytoma in adults confirmed by surgery and pathology were reviewed and studied including MRI manifestation and pathologic data. The ages of the patients ranged from 20 to 68 years old, with a median age of 30 years. Results MRI showed 33 lesions in total with location in cerebellum (n=13),supratentorial parenchyma (n=12), lateral ventricles (n=5), forth ventricle (n=2), and sellar region (n=1). The MRI manifestations showed 5 types:mixed- signal mass in 11 lesions, especially mixed signals on T2WI and enhancement images ; enhanced cystic wall with enhanced mural nodule in 8 lesions on enhancement imaging;non-enhanced cystic wall with enhanced mural nodule in 7 lesions; cystic mass in 5 lesions with high signals on T2WI and enhanced or partially enhanced cystic wall; solid masses in 2 lesions with heterogeneous signal on enhanced imaging. Mild or no edema was identified in 29 tumorsand 4 tumors revealed obvious edema. Hemorrhage was found in 12 tumors and calcification was demonstrated in 4 tumors.. Conclusion Brain pilocytic astrocytoma in adults has characteristic imaging findings on MRI.