颅内恶性畸胎瘤的影像诊断

The imaging analysis of intracranial malignant teratomas

目的 回顾性分析颅内恶性畸胎瘤的影像表现。方法 搜集 15例经手术病理证实的颅内恶性畸胎瘤病人 ,分析其影像表现。本组 15例均行MR检查 ,8例同时进行了CT扫描。结果13例恶性畸胎瘤表现为边缘清楚的分叶状肿瘤 ,由实性部分和小囊变构成。平扫肿瘤呈混杂信号 ,肿瘤实质在T1WI表现为等信号 (6 / 13)或低信号 (7/ 13) ,T2 WI表现为等信号 (2 / 13)或高信号 (11/ 13) ,9例肿瘤T2 WI信号不均匀。 10例肿瘤内出现小囊变或坏死信号 ,囊变可为肿瘤任意位置的少量囊变 ,也可为多数囊变 ;3例无囊变。增强扫描 11例肿瘤呈不均匀强化 ,2例呈均匀强化。本组 2例鞍内型肿瘤信号均匀 ,未见囊变 ,沿漏斗侵犯下丘脑。CT扫描中 8例肿瘤内可见钙化影。本组肿瘤内未见脂肪成分。结论 颅内恶性畸胎瘤具有比较典型的影像学表现 。

Objective To analyse the imaging characters of intracranial malignant teratomas (IMT). Methods The imaging appearances of IMT were analyzed in 15 pathologically proved IMT. MRI were performed on all the 15 cases, CT on 8 of them. Results Thirteen IMT showed as a lobular cyst solid mass with clear borders. The solid portion of IMT displayed iso (6/13) to hypointense(7/13) on T 1WI and iso (2/13) to hyperintense(11/13) on T 2WI. The heterogeneous enhancement was found in 11 cases, homogeneous in 2. Two IMT exhibited as the intrasellar solid lesions involving thalamencephalon. Calcification was found in 8 IMT on CT scan. No fat was demonstrated in the tumor on both CT and MR. Conclusion IMT displays relatively typical appearances on imaging studies. Together with the CT scan, The MR study may make the diagnosis before the operation.