迭代模型重建与iDose4混合迭代重建在头颈部低剂量CT血管成像中的应用比较
Comparison of iterative model reconstruction and iDose4 hybrid iterative technique in low dose head and neck CT angiography
朱维聪 1曾慧芸 1杜晨 1吴雅婷 1王彬1
作者信息
- 1. 523000 广东东莞,东莞康华医院放射科
- 折叠
摘要
目的 探讨迭代模型重建(IMR)对比iDose4混合迭代重建技术在低辐射剂量和低碘摄入量头颈部CT血管成像(CTA)中的应用比较.方法 收集本院2024年1月—5月因需行头颈部联合动脉CTA检查,且身体质量指数不超过30 kg/m2的患者60例,分为对照组和实验组,每组各30例.对照组采用120 kV、150 mAs、对比剂用量50 mL、注射流率5 mL/s和iDose4重建;实验组采用100 kV、100 mAs、对比剂用量30 mL、注射流率3 mL/s,分别使用iDose4和IMR进行图像重建,得到iDsoe4组和IMR组两组重建图像.测量并计算三组图像左侧颈总动脉起始部、左侧颈内动脉起始部和大脑中动脉M1段血管CT值、标准差(SD)、信噪比(SNR)和对比噪声比(CNR);记录并比较对照组和实验组病例容积CT剂量指数、剂量长度乘积,并计算有效剂量.2名诊断医师对图像质量进行主观评分.辐射剂量的比较采用独立样本t检验;CT值、SD、SNR、CNR、主观质量评分的比较采用方差分析或韦尔奇检验,两两比较采用LSD-t检验或Tamhane's T2检验.结果 对照组与IMR组各血管主观质量评分、SD、SNR、CNR的比较差异均无显著性(P＞0.05);iDose4组各血管主观质量评分、SNR、CNR均明显低于对照组和IMR组,差异具有显著性(P＜0.05);对照组各对应血管的CT值均明显高于iDose4组和IMR组,差异具有显著性(P＜0.05);实验组有效剂量(1.62±0.08)较对照组(0.69±0.33)下降了约57.41％,对比剂碘摄入量减少了 40％.结论 在头颈部CTA检查中,采用低管电压、低管电流、低注射剂量及低注射流率联合IMR技术,可在保证图像质量的同时显著地降低患者辐射剂量和碘摄入量,IMR技术在降低图像噪声、提高图像SNR和CNR方面优于iDose4重建.
Abstract
Objective To compare the application of iterative model reconstruction(IMR)and iDose4 hybrid iterative reconstruction technique in head and neck CT angiography(CTA)with low radiation dose and low iodine intake.Methods 60 patients with body mass index ≤30 kg/m2 underwent head and neck CTA in our hospital from January to May 2024.The patients were divided into control group(30)and experimental group(30).The CTA in the control group was performed with 120 kV,150 mAs,50 mL contrast medium injected at the rate of 5 mL/s and iDose4 compared to CTA of the experimental group(100 kV,100 mAs,30 mL,3 mL/s)with iDose4 or IMR.The CT values,standard deviation(SD),signal-to-noise ratio(SNR)and contrast-to-noise ratio(CNR)of the left common carotid artery,internal carotid artery,and M1 segment of the middle cerebral artery,the volume CT dose index and dose-length product and the effective dose were compared between the control and experimental groups.Image quality was scored subjectively by two radiologists.The independent sample t test was used to compare the radiation dose.The CT values,SD,SNR,CNR,and image quality score were analyzed using ANOVA or Welch's test.Pairwise comparisons were performed using LSD-t test or Tamhane's T2.Results There was no significant difference(P＞0.05)in the blood vessel image quality scores,SD,SNR,CNR between IMR and control groups whereas the image quality scores,SNR and CNR of blood vessels in iDose4 group were significantly lower than those in the IMR and control groups(P＜0.05).The CT values of the corresponding vessels in the control group were significantly higher than those in the iDose4 and IMR groups(P＜0.05).The effective dose of the experimental group(1.62±0.08)decreased by 57.41％compared with the control group(0.69±0.33)while the iodine intake of the contrast agent decreased by 40％.Conclusion In head and neck CTA,the application of low tube voltage,low tube current,low injection dose and low injection flow rate combined with IMR technology can significantly reduce the radiation dose and iodine intake of patients while ensuring image quality.IMR technique is better than iDose4 in reducing image noise and improving image SNR and CNR.
关键词
迭代模型重建/辐射剂量/对比剂/CT血管成像Key words
Iterative model reconstruction/Radiation dose/Contrast media/Computed tomography angiography引用本文复制引用
出版年
2024
NETL
NSTL
万方数据