直接法CE-MRV在下肢深静脉血栓中的应用初探

Preliminary Application of Direct Contrast-enhanced MR Venography in Deep Vein Thrombosis of Lower Limb

目的探讨直接法对比增强磁共振静脉血管成像(CE-MRV)在诊断下肢深静脉血栓中的应用价值。资料与方法对临床高度怀疑下肢静脉血栓疾病的27例患者进行直接法减影CE-MRV,将采集的原始数据减影后导入后处理工作站行最大密度投影(MIP),多平面重组(MPR)及表面遮盖(SSD)法重组,分析下肢深静脉血栓形成的影像学表现。结果 27例患者双侧下肢深静脉重组图像显示清晰,重组血管对比度良好,背景抑制满意,6例正常,表现为静脉显影完整,走行自然,原始轴位显示管壁光滑。21例显示不同部位、不同程度的血栓形成,CE-MRV原始轴位图像呈偏心性的充盈缺损,重组图像上显示管腔狭窄、节段性中断或变细、浅静脉代偿扩张、深浅静脉交通支明显增多,侧支循环开放,直接造影法引起的边流效应一般表现为较长节段的中心性充盈缺损,连续断层或MPR图像显示无基底附着于管壁。结果直接法减影CE-MRV检查技术可准确地显示下肢静脉血栓性病变情况,有效避免动脉伪影及周围组织的干扰,图像清晰度及可靠性高,可明确病灶的范围和程度及侧支循环的建立与否,有重要临床应用价值。

Objective To evaluate diagnostic value of direct contrast-enhanced MR venography（CE-MRV） in deep venous thrombosis of lower limb.Materials and Methods 27 patients highly suspected deep vein thrombosis by clinical were underwent direct CE-MRV.The original data was processed with technology of subtraction,and put into workstation and reconstructed with maximum intensity projection（MIP）,multiplanar reformation（MPR）,surface shade display（SSD）.Results Direct CE-MRV showed that the reconstruction image and vascular contrast were very clear,background signal was suppressed satisfactorily in all deep veins of 27 patients.Direct CE-MRV in 6 normal patients displayed complete and regular vein,and the original axial images of these patients showd vessel wall smooth.21 cases displayed different parts and different degrees of thrombosis.Their original axial images showed eccentric filling defect of vascular.On reconstruction image,they displayed tenosis,segmental interruption or thinning in vascular,superficial veins compensatory expansion,deep veins transport branch increased significantly,and collateral circulation opening.A long segment center filling defect was caused by side effects in direct angiography.it displayed no base attached to the vessel wall on continuous axial images or MPR image.Conclusion Direct CE-MRV can be accurately show deep vein thrombosis,avoiding artery artifact and interference from surrounding tissue,its Image is clear and reliable,and display the scope and extent of lesions of the vascular and Whether the Collateral circulation established.Direct CE-MRV has a significant clinical value in diagnosing the thrombotic disease of the lower limb vein.