摘要
目的评价640层CT冠状动脉造影(CTCA)三维自适应迭代剂量降低(AIDR3D)重建算法的图像质量及辐射剂量。方法连续性84例患者接受640层CT自动曝光扫描冠状动脉造影检查,在图像后处理工作站分别采用AIDR3D、滤波反投影(FBP)算法对扫描的原始图像数据进行重建。2位不知道临床信息及重建算法并且富有经验的影像科医生独立测量、计算2种重建算法CTCA的图像噪声、信噪比和对比噪声比,4等级法定性评价CTCA的图像质量。根据CT机扫描输出的剂量长度乘积计算辐射剂量。统计分析比较2种重建算法CTCA的定量及定性图像质量。结果 AIDR3D重建算法CTCA的图像噪声为(27.20±4.40)HU,较FBP(60.00±12.40)HU减少了46.10%,信噪比21.10±5.10较FBP 11.40±2.80提高了84.70%,对比噪声比24.70±5.10较FBP 13.50±3.20提高了82.20%,二者比较均差异有统计学意义(P<0.05)。AIDR3D重建算法冠状动脉近部、中部、远部的图像质量定性评价分数分别为(3.90±0.30)、(3.70±0.50)、(3.60±0.60)分,均高于FBP[分别为(2.60±0.60)、(2.30±0.60)、(2.10±0.70)分],二者比较均差异有统计学意义(P<0.05)。AIDR3D、FBP重建算法可以用于诊断的冠状动脉总段数分别为1 216段(96.50%)、504段(40.00%),二者比较差异有统计学意义(P<0.05)。平均有效辐射剂量为(2.10±1.00)mSv。结论 640层CTCA AIDR3D重建算法不仅较常规的FBP重建算法的图像噪声显著减少,定量及定性图像质量均明显提高,而且有效辐射剂量低。
Objective To investigate the image quality and radiation dose of 640-slice CT coronary arteriography(CTCA)with adaptive iterative dose reduction three-dimensional(AIDR3D)reconstrucction algoritym.Methods 640-slice CTCA with automatic exposure was performed on 84 consecutive patients.The original image data were reconstructed with AIDR3 Dand the filtered back-projection(FBP)algorithms at the image postprocessing workstation.Two experienced radiologists without knowing clinical information and reconstruction algorithms independently measured and calculated the image noise,signal-to-noise ratio and contrastto-noise ratio with AIDR3 Dand FBP reconstruction algorithms.The qualitative image quality was assessed by using the 4-point scale.The radiation dose was calculated based on dose-length product exported on CT scanner.The quantitative and qualitative image quality with two kinds of reconstruction algorithm was analyzed statistically.Results The CTCA image noise was(27.20±4.40)HU with AIDR3Dand(60.00±12.40)HU with FBP,which with AIDR3 Dwas decreased by 46.10%than that with FBP;the signal-to-noise ratio was 21.10±5.10 with AIDR3 D and 11.40±2.80 with FBP,which with AIDR3 D was increased by84.70%than that with FBP;the contrast-to-noise ratio was 24.70±5.10 with AIDR3Dand 13.50±3.20 with FBP,which with AIDR3 Dwas raised by 82.20%than that with FBP,the differences in 3indexes between the two kinds of reconstruction algorithm were statistically significant(P〈0.05).The CTCA qualitative image quality scores of proximal,middle and distal parts with AIDR3Dwere(3.90±0.30),(3.70±0.50)and(3.60±0.60)respectively,which all were higher than(2.60±0.60),(2.30±0.60)and(2.10±0.70)with FBP respectively,the differences in 3items between 2kinds of algorithm had statistical significance(P〈0.05).The total segments which could be used to diagnose the CTCA images with AIDR3 Dand FBP algorithms were 1 216segments(96.50%)and 504segments(40.00%),respectively,the difference had statistical significance(P〈0.05).The mean effective radiation dose was(2.10±1.00)mSv.Conclusion 640-slice CTCA with AIDR3 Dreconstruction algorithm not only significantly reduces the image noise than the conventional FBP algorithm,improves the quantitative and qualitative image quality,but also decreases the effective radiation dose.
出处
《重庆医学》
CAS
北大核心
2015年第10期1358-1361,共4页
Chongqing medicine
关键词
体层摄影术
X线计算机
冠状动脉造影
三维自适应迭代剂量降低
图像处理
计算机辅助
辐射剂量
tomography
X-ray computed
coronary artery angiography
adaptive iterative dose reduction three-dimensional
image processing
computer-assisted
radiation dosage