幕上毛细胞型星形细胞瘤影像学表现

Imaging finding of supratentorial pilocytic astrocytomas

目的:总结幕上毛细胞型星形细胞瘤(PA)影像学特征。方法:回顾性分析11例经手术病理证实的幕上毛细胞型星形细胞瘤CT、MRI表现。结果:11例病变均单发。成人8例,青少年3例。10例发生于中线附近,1例位于大脑半球表浅部位。本组中囊实性病变4例,实性部分呈团块状不均匀强化,囊性部分较小呈小泡样,位于病变一侧,囊壁无强化;实性病变6例,呈不均匀强化;完全囊性病变1例,位于左额叶皮层下区,囊壁及囊腔无强化。11例中出现瘤周水肿2例,均为轻度。结论:幕上PA病变形态及强化方式有其特征性。瘤周水肿无或较轻。病变以成人、大脑中线区多见,诊断应结合临床及多种影像技术以提高诊断正确率。

Objective: To summarize CT and MRI characteristic features of supratentorial pilocytic astrocytomas(PA).Methods: CT and MRI appearance of 8 patients with histological diagnosed supratentorial PA were retrospectively reviewed.Results: All the cases had single lesion.One was child,one was adolescent,others were adults.Most of supratentorial PA were located in the middle line of brain except one in subcortex of frontal lobe.4 tumours showed mixed cystic-solid pattern,the solid part showed massive pattern with intensely enhancement,the cystic wall appeared bullulelike with no enhancement.3 tumours showed solid mass with heterogenous enhancement.Only 1 tumours showed cyst component with no enhancement both on the cyst wall and capsular space.The area of peritumor edema was mild in 2 cases.Conclusion: The appearance and enhancement of supratentorial PA have some characteristics.It has mild peritumor edema.Supratentorial PA mostly locats in the middle line of brain in adults.Preoperative diagnosis can be made in most of cases combined with variety imaging technology and clinical information.