60例中脑肿瘤MR影像分析

Analysis of the MR imaging of 60 cases midbrain tumors

目的 研究６０ 例经手术及病理证实的中脑肿瘤的影像学表现。方法 ６０ 例术前均行 Ｍ Ｒ 显像，手术全部或部分切除。结果 位于中脑顶盖被盖及导水管的肿瘤大多表现为边界比较清楚的异常信号，而丘脑起源累及中脑的肿瘤多为混杂 Ｔ１ 、 Ｔ２ 信号，边界不清。注射 Ｇｄ Ｄ Ｔ Ｐ Ａ 后，局限于中脑的肿瘤大多不增强。而丘脑起源侵及中脑及中脑向桥脑浸润生长的肿瘤多为不均匀混杂增强。结论 位于及累及中脑的肿瘤，生长部位不同，肿瘤性质不同，肿瘤的生物学性质又决定其生长形态，并表现出某些特殊的影像学特征。术前对 Ｍ Ｒ 表现作出正确分析很有意义。

Objective To describe the MRI features of midbrain tumors in 60 cases. Methods MRI was performed in all 60 patients with midbrain tumors. All patients underwent surgical operation. Results Of the 60 patients,MR imaging showed 11 tumors occurred predominantly in the tectum,20 tumors occurred predominantly in the tegmentum and 7 dowmward extension to the pons, 7 tumors located in the cerebral aqueduct. 11 tumors arising in the thalamic region and infiltrate into the mesencephalon. 11pineal tumors secondarily infiltrate the tectum. The histological diagnosis was low grade astrocytoma in 11 cases, highgrade astrocytoma in 15 cases,oligo astrocytoma in 5 cases, fibrillary astrocytoma in 5 cases, ependymoma in 2 cases, glioblastoma in 11 cases, another 11 cases was pineal parenchymal tumors and germinal cell tumors.Conclusion There exist a wide variation of MRI features related to the site and pathology of midbrain tumors. With the advent of MRI, the delineation of the lesions is more precisely presented, and the tumor type can usually be correctly assumed.