摘要
目的:探讨颈动脉CTA扫描时通过降低管电压以达到降低辐射剂量的可行性。方法:将40例需行颈动脉CTA检查的患者依据管电压不同而分为A(120 kV)、B(80 kV)两组,每组20例。分析比较两组图像的CT值、对比噪声比(CNR)、信号噪声比(SNR)及辐射剂量,并对重建图像质量、血管边缘形态进行评估分析。结果:B组容积CT剂量指数(CTDIvol)、剂量长度乘积(DLP)及有效剂量(ED)较A组分别降低63.97%、63.83%及63.79%,图像质量评价结果:B组颈动脉平均CT值较A组显著增加,差异具有统计学意义(P<0.05)。A、B两组CNR、SNR值组间比较及两两比较差异均无显著统计学意义(P>0.05);且A、B两组颈动脉重建图像质量、血管边缘形态整体满意,无明显差别(P>0.05)。结论:80 kV低管电压颈动脉CTA扫描在不影响图像质量的前提下,最大能够降低约64%的辐射剂量。因此,颈动脉CTA检查通过降低管电压的低剂量扫描是可行的,可常规使用。
Objeetlve： To explore the carotid artery CTA scan through lower tube voltage in order to achieve the feasibility of reducing radiation dose. Method ： 40 patients of required carotid artery CTA examination were divided into two groups ： according to the tube voltage A （ 120 kV ）, B （ 80 kV ）, 20 cases in each group. Analysed and compared two sets of image CT value, contrast to noise ratio （ CNR ）, signal to noise ratio （ SNR ） and radiation dose, meantime evaluated the reconstructed image quality, vascular morphology. Result： The CT dose index （ CTDIvol ）, dose length product （ DLP ） and the effective dose （ ED ） in group B were lower than in group A 63.97%, 63.83% and 63.97%. The results of image quality evaluation： the mean CT value of group B was significantly higher than group A; The difference had statistical significance （ P〈0.05 ） . The difference of CNR, SNR hadn＇t statistical significant （ P〉0.05 ）. And two groups＇ carotid reconstruction image quality, blood vessels, marginal form the overall satisfaction, no significant difference （ P〉0.05 ） .Conclusion： Using low tube voltage （ 80 kV ） can lower 64% radiation dose.It is proved to be effective and feasible in carotid CT angiography.
出处
《中国医学创新》
CAS
2013年第28期79-82,共4页
Medical Innovation of China
关键词
体层摄影术
辐射剂量
管电压
图像质量
Computer tomography
Radiation dose
Tube voltage
Image quality
