不同低千伏下胸腹动脉联合CT扫描图像质量的差异研究

Study on the difference of image quality of thoracoabdominal artery combined with CT under different low kilo-volt

目的研究第三代双源CT 2种低千伏检查在胸腹动脉联合扫描中图像质量的差异。方法回顾性纳入20例患者,男性11例、女性9例;使用第三代双源CT进行胸腹动脉联合扫描。根据管电压分为80 kV组10例,90 kV组10例。比较2组患者年龄、性别的差异性;记录比较2组患者主动脉、肺动脉、冠状动脉CT值和信噪比;比较2组患者的辐射剂量,并对2组样本数据进行独立样本t检验。结果2组患者的性别年龄之间差异无统计学意义(P>0.05);在80 kV组主动脉,肺动脉和冠状动脉的CT值分别为(553±101)HU、(713±200)HU、(546±82)Hu,90 kV组分别为(460±95)HU、(487±109)HU、(450±62)HU,80 kV组CT值高于90 kV组,且差异有统计学意义(P<0.05);2组之间信噪比的差异无统计学意义(P>0.05);80 kV组平均辐射剂量为(4.2±0.5)mSv,90 kV组为(5.5±0.6)mSv,80 kV组辐射剂量比90 kV组降低,差异有统计学意义(P<0.05)。这些图像均能够满足影像诊断。结论使用第三代双源CT 80 kV检查条件在胸腹动脉联合扫描的检查中能实现同90 kV组同样的图像质量且辐射剂量明显降低,对临床具有很大的意义。

Objective To study the difference of image quality between the third generation dual source CT and two kinds of low kilovolt(kV)in the combined scan of thoracoperitoneal artery.Methods Twenty patients(11 males and 9 females)were enrolled in the study.The combined thoracoabdominal artery scanning was performed with the third generation double source CT.According to the voltage of the tube,they were divided into two groups:80 kV group and 90 kV group,both groups were 10 cases.The differences of age and sex between the two groups were compared;the CT values and signal-to-noise ratio(SNR)of aortic,pulmonary artery and coronary artery were recorded and compared between the two groups.The radiation doses of the two groups were compared,and the samples of the two groups were compared.The data were tested by independent sample t test.Results There was no significant difference in sex and age between the two groups(P>0.05).The CT values of aortic,pulmonary artery and coronary artery in 80 kV group were(553±101)HU,(713±200)HU and(546±82)HU,respectively,and those in control group were(460±95)HU,(487±109)HU,(450±62)HU.the CT values in 80 kV group were significantly higher than those in 90 kV group.There was statistical difference(P<0.05).There was no significant difference in SNR between the two groups(P>0.05).The average radiation dose was(4.2±0.5)mSv in the group and(5.5±0.6)mSv in the control group,which was significantly lower in the experimental group than in the control group(P<0.05).These images can satisfy the diagnosis.Conclusion The third generation dual-source CT 80 kV can achieve the same image quality as the 90 kV group in the combined thoracoabdominal artery scanning,which is of great significance to the clinic.