脊髓星形细胞瘤的MRI诊断

The MR Imaging of Intramedullary Astrocytomas

目的 分析脊髓星形细胞瘤的MRI表现。方法 回顾性总结了 50例经手术病理证实的脊髓星形细胞瘤的MR影像资料。结果 在T1WI肿瘤多表现为等信号或低信号 ;在T2WI多表现为高信号。 2 5例肿瘤有瘤内囊变 ;2 2例在肿瘤一端或两端有脊髓继发囊腔形成。增强扫描后 ,3 3例肿瘤边界不清 ,1 7例边界清楚。 3 0例肿瘤轻度强化 ,1 4例明显强化 ,6例未强化。 44例肿瘤强化不均匀 ,其中 2 2例呈散在斑片状强化 ,1 5例呈结节状或团块状强化 ,7例呈大片状强化。结论 MRI增强扫描对于脊髓星形细胞瘤的诊断非常重要 ,其MRI表现具有一定特征性 :好发于颈胸段脊髓 ;多呈偏心性生长 ,脊髓背侧较常见 ;肿瘤边界多不清。

Purpose To study the MRI findings of intramedullary astrocytomas. Methods MR images of fifty patients with intramedullary astrocytomas proved by operation and pathology were reviewed retrospectively. Results The tumor showed mainly isointensity or hypo intensity on T1WI and hyper intensity on T2WI. Intratumoral cysts were seen in 25 tumors, rostral or caudal cysts were seen in 22 tumors. On contrast enhanced studies, the margins were considered ill defined in 33 and well defined in 17 tumors. The tumors exhibited gentle enhancement (30/50), intense enhancement (14/50) and no enhancement (6/50). 44 tumors had uniform enhancement, 22/44 were scattered patch enhancement, 15/44 were nodulous or mass enhancement, 7/44 were large piece enhancement. Conclusion Contrast MRI is very important in diagnosing intramedullary astrocytomas. There are some characteristics: Astrocytomas located most frequently in cervical and thoracic region, often eccentrically located, usually in the posterior aspect of the cord. Astrocytomas often had gentle scattered patch enhancement with ill defined margins.