低kV迭代算法CT血管成像术前定位Adamkiewic动脉的应用研究

Application evaluation of preoperative location of adamkiewic artery by CT angiography with 100 kV combined interative metyod

目的探讨低kV迭代算法重建CT血管成像在主动脉病变术前定位Adamkiewic(AK)动脉的可行性、临床价值及优势。方法对36例因主动脉病变行主动脉腔内修复的患者,行低kV(100kV)320排CT主动脉血管成像,对原始数据进行迭代算法重建后进行容积再现(VR)、最大密度投影(MIP)及多平面重组(MPR),计算AK动脉的显示率;分析CTA对AK动脉的起源位置及走行的显示情况;采用3分法对图像质量进行评价;并计算患者的辐射剂量。与常规kV(120kV)传统的滤波反投影重建图像进行对比研究。结果冠状面及斜冠状面图像AK动脉呈典型的"发卡"状结构;低kV组及常规kV两组病例AK动脉显示率分别为88.89%(32/36)及88.46%(23/26),两组间差异无统计学意义;两组病例AK动脉图像质量分级无明显差异;而低kV组患者辐射剂量仅为常规kV组的69.27%。结论低kV迭代算法重建CT血管成像可以清晰的在主动脉病变术前定位AK动脉,同时大大降低患者的辐射剂量。

Objective To explore the clinical value of preoperative localization of adamkiewicz artery by 320‐row compu‐ted tomography （CT） angiography for patients undergoing endovascular aortic repair with 100 kV combined iterative meth‐od .Methods 36 patients with aortic lesions underwent 320‐row CT angiography with 100 kV .Images were reconstructed by iterative algorithm method .Volume rendering （VR） ,the axial ,coronal and oblique coronal multiplanar reformations （MPR） and maximum intensity projections （MIP） were generated and displayed .The detected ratio ,image quality of AKA and radiation dose were evaluated and compared with those of 120 kV group .Results AK artery was typically shown as ＂hairpin＂‐like structure in coronal and oblique coronal image .The detected ratio of AKA was 88 .89% （32/36） and 88.46% （23/26） respectively in 100 kV group and 120 kV group .There were no significant differences between the two groups for the detected ratio and image quality .The mean effective dose for the 100 kV group was significantly lower than that for the 120 kV group （9 .94 and 14 .35 mSv） ,with a reduction of radiation dose of 31 .73% .Conclusion 100 kV combined iterative method of CT angiography can localize AK artery accurately ,while significantly reducing the radiation dose of the patient .