多层螺旋CT肾动脉成像的图像后处理技术及临床应用

目的探讨多层螺旋CT肾动脉成像的各种图像后处理技术对肾动脉变异和不同病变显示的优缺点及临床应用价值。方法分析使用多层螺旋CTA检查肾动脉的51例患者的血管重建图像,比较各种图像后处理技术对肾动脉变异及不同病变的显示效果。29例与同期数字减影动脉造影(DSA)检查结果进行比较。51例患者中包括肾动脉变异12例、肾动脉狭窄27例、肾动脉瘤3例、肾动脉栓塞3例、肾动脉夹层6例。3例经手术证实,29例经DSA检查证实,19例经MRA等其他相关检查和随访证实。结果51例患者都能清晰显示变异的肾动脉、副肾动脉及肾动脉病变,特异度100%,灵敏度100%。29例患者与同期DSA图像对比,肾动脉的变异情况、病灶的部位、范围完全一致。各种常用图像后处理技术中,MPR难以完整显示血管的解剖学全貌,但能清晰显示肾动脉钙化、狭窄、栓塞、夹层、动脉瘤及肾内梗塞灶。MIP既能清晰显示肾动脉的解剖学形态,又能清晰显示不同病灶。VR能完整显示肾动脉的解剖学形态,在发现副肾动脉和对重叠血管、动脉瘤的显示方面优于MIP,但不能显示血管腔内情况。SSD可显示复杂的血管解剖学形态,但受阈值选择的影响较大。CPR可将迂曲的肾动脉伸展,显示较直观,并可应用来测量肾动脉狭窄处的截面积。结论MSCTA可直观地、准确地显示肾动脉变异及病变。肾动脉成像的各种后处理技术中,MIP和VR两者联合应用对肾动脉变异及病变显示最佳;MPR及SSD亦有很好的辅助作用。

The postprocessing techniques in renal artery reconstructions and clinical application with multidetector spiral CT angiography

Objective To investigate the value and predominance for imaging po stprocessing techniques of renal artery variation and lesions by multidetector s piral CT angiography. Methods 51 patients with renal artery disease including 12 artery variation, 27 artery stenosis, 3 renal aneurysm, 3 thrombosis of renal a rtery and 3 dissecting aneurysm of renal artery by SSD, MIP and CPR were enrolle d.The effectiveness of these imaging postprocessing methods was compared, 29 of them were confirmed by DSA and 3 by operation, others were checked by MRA and fo llow up. Results All abnormalities and diseases were clearly displayed. The spec ificity and sensitivity were 100%respectively. In the all imaging postprocessin g techniques, MPR can clearly display the calcification of the arteries, stenosi s, embolism, aneurysm but do not display the anatomy satisfactorily. MIP can not only clearly display the anatomy but display the different configurations. VR c an display the artery figures but can not display the information of lumen of bl ood vessels. SSD can display the complex vessel anatomy but it was influenced by its threshold selection. CPR can spread and display directly the tortuous renal artery and measure the section area of stenosis. Conclusions MSCTA is helpful t o accurately display the renal artery variation and lesions . Both MIP and VR ar e the best choice to illustrate the renal artery abnormalities. And MPR and SSD are assistant in the diagnosis of renal artery lesions.