MRI diagnosis of intracranial pilocytic astrocytoma
YAN Jing1, CHENG Guan-xun1, ZHU Xiao-jun1, LIU Guo-shun1, YU Kang-hui1, ZHANG Gang2
1. Imaging Center of Nanfang Hospital Affiliated to Southern Medical University, Guangzhou 510515, China;2. Department of Radiology, Guangdong Hospital of TCM, Guangzhou 510120, China
Abstract：Objective: To investigate the MRI features of intracranial pilocytic astrocytoma(PA) to further enhance the understanding of the disease. Methods: The pre-and-post contrast MR images of 18 cases of pathologically confirmed PA were analyzed retrospectively. Results: Of the 18 PA, 9 located in the midline structure(5 in the optic chiasm, 2 in the brainstem, 1 in the hypothalamus and 1 in the fourth ventricle), 5 in the cerebellum and 4 in the cerebral hemisphere. The size of lesions ranged from 2.1cm to 5.9cm. On MRI, 10 cases were predominantly solid mass with cystic degeneration or necrosis or micro-cystic components, all had markedly inhomogeneous enhancement; Eight cases were solid-cystic mass, 4 with intensely enhancing mural nodule and cystic wall, 3 with intensely enhancing mural nodule and non-enhancing cystic wall and 1 with mildly enhancing mural nodule and cystic wall. Thirteen cases showed no obvious peritumoral edema and 5 showed slight peritumoral edema. Conclusion: The MRI appearance of PA has some characteristics. According to the clinical manifestations, it is helpful for accurate preoperative diagnosis. Meanwhile, it also offers significant reference value for treatment.
2011, Vol. 22 
