基于迭代重建技术的低辐射剂量和低对比剂剂量在肝脏增强CT中的应用研究

发布时间：2018-10-19 07:13

【摘要】：目的探讨肝脏CT增强图像中应用AIDR 3D技术结合低对比剂剂量时的图像质量及辐射剂量。方法前瞻性的将150例行常规肝脏增强CT的患者随机分为3组(A、B、C组),每组50例。A组(常规组)为FBP重建+常规对比剂用量(1.5 ml/kg);B组及C组为双低组,其中B组为AIDR 3D重建+低对比剂用量(1.0 ml/kg),C组为FBP重建+低对比剂用量(1.0 ml/kg)。定量计算3组图像的有效辐射剂量、平均CT值、图像噪声、信噪比(SNR)、对比信噪比(CNR)。对3组图像的诊断信息(图像主观噪声、图像总体质量)按1~4分(1分最差,4分最优)予以评分。计量资料采用完全随机设计的方差分析及秩和检验。计数资料采用完全随机设计的非参数检验(Kruskal Wallis)对结果进行比较。结果双低组(B组及C组)的有效剂量较常规组(A组)降低约23.4%;B组和C组之间差异无统计学意义(P0.05)。图像质量客观评估中,B组图像噪声低于A组,C组图像噪声高于A组(P0.01)。B组的CNR与A组相比,差异无统计学意义(P0.05);C组的CNR低于A组和B组(P0.01)。B组的SNR高于A组,C组的SNR低于A组(P0.01)。主观评估中,B组的图像质量评分高于A组(P0.01);C组的图像质量评分低于A组(P0.01)。结论 AIDR 3D重建技术结合低对比剂剂量扫描,在降低CT辐射剂量及减少对比剂用量的条件下,仍可获得与FBP重建结合常规对比剂用量扫描相当甚至更好的图像质量。
[Abstract]:Objective to investigate the image quality and radiation dose of liver CT enhanced images using AIDR 3D technique combined with low contrast dose. Methods one hundred and fifty patients with conventional liver enhanced CT were randomly divided into 3 groups (50 cases in each group). Group A (routine group) was treated with conventional contrast agent for FBP reconstruction (1.5 ml/kg); B group) and group C was double low group (group C). The dosage of AIDR 3D reconstruction low contrast agent was used in group B (1.0 ml/kg), C) and FBP reconstruction low contrast agent dosage (1.0 ml/kg). Quantitative calculation of effective radiation dose, mean CT value, Image noise and SNR (SNR), compared with SNR (CNR). The diagnostic information of three groups of images (image subjective noise, image total quality) was rated as 1 ~ 4 (1 was the worst and 4 was the best). The variance analysis and rank sum test of complete random design were used to measure the data. The counting data were compared by (Kruskal Wallis) with complete random design nonparametric test. Results the effective dose of double low group (group B and group C) was lower than that of group A (23.4%). There was no significant difference between group B and group C (P0.05). In the objective evaluation of image quality, the image noise of group B was lower than that of group A, and the image noise of group C was higher than that of group A (P0.01). B group compared with group A, the CNR of group A was lower than that of group A (P0.05) the CNR of group); C was lower than that of group A (P0.01). B group was higher than that of group A, and the SNR of group C was lower than group A (P0.01). In subjective evaluation, the image quality score of group B was higher than that of group A (P0.01); C group was lower than that of group A (P0.01). Conclusion with the combination of AIDR 3D reconstruction and low contrast dose scan, under the condition of reducing the radiation dose of CT and reducing the dosage of contrast agent, the image quality can be obtained even better than that of FBP reconstruction combined with conventional contrast agent.
【作者单位】：江苏省常州市第四人民医院CT室;
【分类号】：R816.5

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