软组织神经源性肿瘤的MRI诊断

MRI Diagnosis of Neurogenic Tumor in Soft Tissue

目的：评价ＭＲＩ对软组织神经源性肿瘤的诊断价值。材料与方法：回顾分析１３例软组织神经源性肿瘤的ＭＲＩ表现，其中良性神经源性肿瘤１０例，恶性３例，均经手术病理证实。结果：大部分肿瘤表现为卵圆形或梭形（ｎ＝１１），边界清晰（ｎ＝１１），与邻近神经血管束关系密切（ｎ＝１２）。Ｔ１ＷＩ上均匀或轻度不均匀（ｎ＝９），均为等于或稍高于肌肉信号。Ｔ２ＷＩ上为中等或明显不均匀（ｎ＝１０）高信号，仅１例神经纤维瘤于Ｔ２ＷＩ上表现为“靶征”。ＧｄＤＴＰＡ增强后为不均匀（ｎ＝１０）中等或明显强化。结论：结合肿瘤的形态和ＭＲ信号特点，可提示软组织神经源性肿瘤的诊断。而良、恶性神经源性肿瘤的ＭＲＩ表现无特异性。

Objective: To evaluate MRI in the diagnosis of neurogenic tumor in soft tissue. Materials and Methods: MRI features of neurogenic tumor in soft tissue, benign ( n= 10) and malignant ( n=T5BZ3), were analyzed in 13 pathologically proved patients. Results: Most tumors presented as an ovoid or fusiform mass with welldefined margins ( n= 11). The tumor was close to neurovascular structure ( n= 12). On T1WI, most tumors showed homogeneous or mild inhomogeneous signal and the signal intensity was equal to, or mildly higher than, that of muscle. On T2WI, 10 tumors showed high signal intensity and were mildly or markedly inhomogeneous. Of 11 cases using GdDTPA, 10 showed mild to marked inhomogeneous enhancement. Target sign was seen in one neurofibroma. Conclusion: Based on morphological and signal characteristics on MRI, the diagnosis of neurogenic tumor can be suggested. MRI is not very helpful in differentiating benign from malignant.