MRI与4DCEMRA鉴别肢体脂肪性肿瘤良恶性的意义

The value of the combination of MRI and four-dimensional contrast enhanced MR angiography in the differenation of benign and malignant fatty tumors of limb

目的:探讨MRI联合4DCEMRA鉴别肢体脂肪性肿瘤良恶性的意义。方法:对7例肢体脂肪肉瘤和7例肢体脂肪瘤的MRI、4DCEMRA资料进行回顾性分析;比较二者MRI、4DCEMRA的差异。结果:MRI信号:脂肪肉瘤T1WI信号复杂、不均匀,表现为低至高各种信号或混杂信号;T2WI呈不均匀稍高、高信号为主;FS-T2WI呈不均匀高信号,T1WI所示高信号呈等信号;病灶呈明显或中度不均匀强化,3例伴有厚分隔、2例伴有薄分隔。脂肪瘤T1WI、T2WI呈高信号,4例伴有薄分隔;FS-T2WI呈等信号;分隔中度强化,余未见强化。4DCEMRA表现:脂肪肉瘤可见异常动脉分支进入瘤体,供血动脉显示、瘤体可见染色;瘤周引流静脉增多、增粗。脂肪瘤未见肿瘤血管染色及供血动脉。结论:MRI联合4DCEMRA对鉴别肢体脂肪性肿瘤良恶性具有定性诊断价值。

Objective： To evaluate the role of MRI and four-dimensional dynamic contrast enhanced magnetic reso- nance angiography （4D CEMRA） in diagnosing benign and malignant fatty tumors of limb. Methods：MRI and 4D CEMRA findings of ？ patients with liposarcoma and 7 patients with lipoma of the extremities were retrospectively reviewed. The differences of MRI and 4D CEMRA between liposarcoma and lipoma were compared. Results： Signs of MRh On T1WI the signs of liposarcoma were complicated and varied from hypo-intensity to hyperqntensity;On T2 WI the lesions demonstrated mainly heterogeneous slight hyper-intensity or hyper-intensity;On FS-T2 WI the lesions demonstrated heterogeneous hyper- intensity,the hyper-intensity shown in T1WI manifested iso-intensity. On gadolinium contrasted MR scanning, 4 cases showed obviously heterogeneous enhancement and the other 3 cases showed medium heterogeneous enhancement; 3 cases showed thick septum and 2 cases showed thin septum. The lipoma in the ？ cases demonstrated mainly hyper-intensity on T1 WI and T2 WI with linear hypo-intensity of thin septum in 4 cases;On FS-T2 WI, the lesions demonstrated mainly iso-in- tensity,and the septa manifested slight hyper-intensity. They showed no enhancement except the enhanced septa. Manifesta- tions on 4D CEMRA： The liposarcoma showed the feeding artery and tumoral staining, and increased and dilated draining veins as well. No tumor vascular staining and feeding artery were shown in lipoma. Conclusion： The combination of MRI and 4D CEMRA has a definite value for the differential diagnosis of benign and malignant fatty tumors of limb.