【摘要】 目的探讨256层螺旋CT idose4迭代重建结合"三低"(低辐射剂量、低剂量及低浓度对比剂)主动脉成像的可行性。方法前瞻性将70例BMI为18.5～25.0kg/m~2、且需接受全主动脉CTA检查的患者,随机分为常规组及"三低"组,各35例。常规组扫描参数:管电压120kV,管电流250mAs,对比剂浓度370mgI/ml,对比剂剂量1.5ml/kg;"三低"组扫描参数:管电压80kV,管电流250mAs,对比剂浓度300mgI/ml,对比剂剂量1.0ml/kg。两组均采用idose4迭代重建算法,其余扫描参数一致。两组图像质量主、客观评价结果的比较及辐射剂量的比较采用SPSS 13.0软件进行统计学分析,P<0.05为差异有统计学意义。结果两组图像质量的主观评分无明显差异(P>0.05);两组主动脉图像各水平段的CT值均为差异有统计学意义(P均<0.05);两组主动脉图像各水平段的SNR、CNR均为差异无统计学意义(P均>0.05)。两组ED、DLP及对比剂剂量的差异均具有统计学意义(P均<0.05)。结论 256层螺旋CT idose4迭代重建结合"三低"主动脉成像方法确切可行,图像质量可满足临床诊断要求,并能大幅度降低辐射剂量及对比剂剂量。更多还原

【Abstract】 Objective To investigate the feasibility of 256 slice spiral CT with iDose4 iterative reconstruction and "three low"(low dose, low iodinated concentration and tow contrast agent volume) in aorta CT angiography. Methods Seventy patients whose body mass indexes(BMI) ranged from 18.5 to 25.0 kg/m~2 underwent aorta CTA. All patients were randomly divided into control group and "three low" group, with 35 patients in each group respectively. The parameters of control group were as follow: tube voltage 120 kV, tube current 250 mAs, iodine concentration of contrast agent 370 mgI/ml, dose of contrast agent 1.5 ml/kg. However, those of "three low" were as follow: tube voltage 80 kV, tube current 250 mAs, iodine concentration of contrast agent 300 mgI/ml, dose of contrast agent 1.0 ml/kg, iDose4 iterative reconstruction was adopted in both groups, moreover, the other parameters were same. The imaging qualities of both groups were subjectively and objectively assessed. The subjective and objective evaluation of image quality in two groups as well as radiation dose were compared statistically by SPSS software, and the level of statistical significance was set at P<0.05. Results There was no significant difference in image quality subjective score between two groups(P>0.05). The difference of aorta CT value between the two groups was statistically significant(P<0.05), however, there was no statistical important difference in SNR and CNR between the two groups(P>0.05). The differences of the CTDI vol, DLP, ED and the contrast medium volume between the two groups were statistically significant(P<0.05). Conclusion The way of 256-slice spiral CT combined with iDose4 iterative reconstruction and "three low" is feasible for aorta CT angiography; based on the premise of satisfying the clinical diagnostic requirements, the radiation dose and the contrast medium volume can be greatly reduced.更多还原