摘要
目的 探讨80 kV管电压256层螺旋CT主动脉造影降低射线剂量的可行性.方法 对62例疑似主动脉疾病的患者进行主动脉CT造影成像,分为常规管电压扫描组（120 kV扫描组）和低管电压扫描组（80 kV扫描组）,每组31例.然后对两组图像信号噪声比、对比度噪声比和有效剂量进行评估.结果 120与80 kV2个扫描组的图像信号噪声比分别为（35.92±5.04）和（33.95±8.30）,对比度噪声比分别为（30.32±4.78）和（28.71±7.96）,差异均无统计学意义（t=1.131、0.964,P＞0.05）.而二组的有效剂量分别为（14.28±0.96）和（9.72±0.81）mSv,差异有统计学意义（t=20.12,P＜0.001）.结论 同120 kV管电压比较,80 kV管电压主动脉CT造影在没有降低图像质量的情况下,射线剂量降低约31.9%,同时降低造影剂剂量50%.
Objective To evaluate the feasibility of 80 kV tube kilovoltage in aortic artery CT angiography with 256-slice CT. Methods A total of 62 patients undergoing aortic artery CTA were enrolled into this study and divided into conventional tube kilovoltage （120 kV, n = 31 ） and low tube kilovoltage （80 kV, n = 31 ）. The signal-to-noise ratio （SNR） , contrast-to-noise ratio （CNR）, volume CT dose index （CTDIvol） and effective dose （E） were evaluated, respectively. Results The mean image SNR was （ 35.92 ± 5.04） and （ 33.95 ± 8. 30） for conventional tube kilovoltage and low tube kilovoltage,respectively, with no significant difference （t = 1. 131, P =0. 263）. The mean image CNR was （30. 32 ±4.78） and （28.71 ± 7.96 ） for conventional tube kilovoltage and low tube kilovoltage, respectively, with no significant difference （ t = 0. 964, P = 0. 339 ）. The average effective dose （ E ） was （ 14. 28 ± 0.96 ）mSv and （9. 72± 0. 81 ）mSv for conventional tube kilovoltage and low tube kilovoltage, respectively, with significant difference （ t = 20. 12, P ＜ 0. 001 ）. Conclusions 80 kV tube kilovoltage aortic artery CTA can reduce radiation dose by 31.9% , and contrast dose 50% ,and maintain image quality compared with 120 kV tube kilovoltage.
出处
《中华放射医学与防护杂志》
CAS
CSCD
北大核心
2010年第6期740-743,共4页
Chinese Journal of Radiological Medicine and Protection
