MRI成像对毛细胞型星形细胞瘤的诊断价值

The Value of Magnetic Resonance Imaging for Pilocytic Astrocytoma

目的研究MRI成像对毛细胞型星形细胞瘤的诊断价值。方法回顾性分析11例术前MRI检查术后病理证实为毛细胞型星形细胞瘤的MRI资料,总结MRI信号特征。结果肿瘤发生在小脑的有7例,大脑的有4例。11例病例中,完全囊性有2例,囊实性的有6例,完全实性的有3例。出现壁结节的有4例,有6例出现第四脑室受压和幕上脑室积水。肿瘤的实性部分一般T1WI呈低信号或等低信号,T2WI呈高信号或等高信号,而DWI图像上实性部分表现为低信号。增强后肿瘤实性部分明显强化,囊性部分不强化。结论毛细胞型星形细胞瘤的MRI表现具有一定的特征性,磁共振检查可作为首选术前诊断方法。

Objective To investigate the value of magnetic resonance imaging （MP-I） for pilocytic astrocytoma （PA）. Methods 11 patients with PA proven by pathology were selected in study, and their pre-operation MRI findings were analyzed and sununarized retrospectively. Results Tumor located at cerebellum （7 cases） and cerebral hemisphere （4 cases） among all the 11 cases and could be classified as cyst （2 cases）, cyst with nodule （6 cases） and mass （3 cases）. Mural nodule appeared in 4 cases. Furthermore, displacement of the fourth ventricle and dropsy of supratentorial ventricle appeared in 6 cases. The solid component of tumor appeared as hypointense or isointense on T1WI, hyperintense or isointense on T2WI and hypointense on DWI. After administration of Gd-DTPA intravenously, the solid part showed obvious enhancement while the cystic part appeared little. Conclusion There is characteristic appearance of PA in MRI that could be a used as preferential method for pre-operation diagnosis.