迭代重建技术在CT上腹部低剂量扫描中的应用效果及价值研究

摘要

Objective To observe the application effect and value of iterative reconstruction technique in upper abdominal low-dose CT scanning.Methods Sixty patients with abdominal CT scanning in the hospital from June 2015 to September 2016 were se-lected and randomly divided into the control group(n=30)and observation group(n=30).The control group conducted the conven-tional dose abdominal scan at 120 kV and 250 mAs.The obtained images were reconstructed by adopting the filter reflex images. The observation group conducted the upper abdominal low-dose scan under the tube voltage of 120 kV and tube current of 250-270 mAs and at a interval of 60mAs reduced scan condition.The obtained images were reconstructed by iterative technique.Then the application effect of iterative reconstruction technique in upper abdominal low-dose CT scanning was analyzed.Results The cases number of subjective score 1,2 and 3 points for image quality in the observation group was lower than that in the control group, difference was statistically significant(P<0.05);The cases number of subjective score 4 points for image quality in the observation group was more than that in the control group,difference was statistically significant(P<0.05);the obtained values of image noise, spinal erector muscle noise and abdominal wall fat noise in the observation group were less than those in the control group,the difference was statistically significant(P<0.05);The CT dose index,CT dose length product and effective radiation dose level after iterative reconstruction technique treatment in the observation group were lower than those in the control group,the difference was statistically significant(P<0.05).Conclusion Adopting the iterative technique reconstruction in upper abdominal CT scanning has an ideal effect,can reduces the image noise and radiation dose,moreover the radiation dose reduction by 35% can still obtain the cor-responding image quality by the conventional dose,which is worthy to be promoted and applied.%目的 观察迭代重建技术在CT上腹部低剂量扫描中的应用效果及价值.方法 选取2015年6月至2016年9月该院收治的上腹部CT扫描患者60例,分为对照组(n=30)和观察组(n=30).对照组在120 kV、250 mAs下进行常规剂量腹部扫描,获得的图像采用滤波反射影进行重建;观察组在管电压120 kV、管电流于250~70 mAs每次间隔60 mAs减低扫描条件下行上腹部低剂量扫描,获得的图像采用迭代技术进行重建,分析迭代重建技术在CT腹部低剂量扫描中的应用效果.结果 观察组图像质量主观评分为1分、2分及3分患者例数低于对照组,差异有统计学意义(P<0.05);观察组图像质量主观评分4分患者例数多于对照组,差异有统计学意义(P<0.05);观察组获得图像中噪声、竖脊肌噪声及腹壁脂肪噪声值少于对照组,差异有统计学意义(P<0.05);观察组迭代重建技术处理后CT剂量指数、CT剂量长度乘积及有效辐射剂量水平低于对照组,差异有统计学意义(P<0.05).结论 上腹部CT扫描患者采用迭代技术重建效果理想,能降低图像噪声及辐射剂量,且辐射剂量降低35% 仍能获得与常规剂量相对的图像质量,值得推广应用.