摘要
目的探讨不同管电压及管电流在迭代重建算法图像中对图像质量及相应辐射剂量的影响程度。方法利用仿真人体模型在不同管电压(80、100、120kV)及管电流(15、20、25、30、100、200mAs)条件下进行分次成像,对图像质量(主观和客观评价)进行评价,并记录分次成像辐射剂量,分析辐射剂量与图像质量的相关性。结果管电压不变时,不同管电流(15、20、25、30、100、200mAs)图像质量(对比噪声比:CNR及信噪比:SNR)比较,差异有统计学意义(P<0.05);管电流不变时,不同管电压(80、100、120kV)图像质量比较,差异有统计学意义(P<0.05);管电流不变时,随管电压增加,椎体CT值逐渐降低(P<0.05);肺野CT值比较,差异无统计学意义(P>0.05)。分析不同管电压下图像质量与辐射剂量的关系,并确立相关性方程:80kV:Y=2.625X+0.038;100kV:Y=14.66X+0.158;120kV:Y=18.59X+0.093。结论图像质量随管电流及管电压的增加逐渐上升,辐射剂量随管电压及管电流的上升相应增加;适当降低管电压,增加管电流可降低辐射剂量。
Objective To investigate the effect of different tube voltages and currents on the image quality and radiation dose in the image by the iterative reconstruction algorithm. Methods The simulated human body model was used to perform the CT scans with different tube voltages (80, 100 and 120 kV) and tube currents (15, 20, 25, 30, 100 and 200 mAs) respectively. The image quality was evaluated both subjectively and objectively and the radiation dose of each time was recorded. The correlation between the radiation dose and image quality was analyzed. Results When the tube voltage was constant, the image quality of different tube currents (15, 20, 25, 30, 100 and 200 mAs) was statistically different ( P <0.05). When the tube current was constant, the image quality of different tube voltages (80, 100 and 120kV) was statistically different ( P <0.05) and the CT value of vertebral body decreases gradually with the increase of tube voltage ( P <0.05). There was no significant difference in the CT value of lung field ( P >0.05). The correlation equations were established by analyzing the relationship between the image quality and radiation dose under different tube voltages and they were as follows: 80kV: Y=2.625x+0.038;100kV: Y=14.66x+0.158;120kV: Y=18.59x+0.093. Conclusion The image quality and radiation dose increase with the increase of tube current and tube voltage, and the radiation dose can be reduced by appropriately decreasing the tube voltage and increasing the tube current.
作者
彭盛坤
赵原
蒲红
廖宗慧
李方
何岳峰
Peng Shengkun;Zhao Yuan;Pu Hong;Liao Zonghui;Li Fang;He Yuefeng(Radiology Department, Sichuan Provincial People's Hospital, Chengdu 610072, China)
出处
《成都医学院学报》
CAS
2019年第4期447-450,共4页
Journal of Chengdu Medical College
基金
四川省卫计委普及应用项目(No:16PJ465)
