摘要
目的探讨全模型迭代重建(IMR)、高级混合迭代重建(iDose^4)及滤波反投影(FBP)重建算法在不同管电压条件下冠状动脉CT成像中对图像质量的影响。方法选取小型猪5只,每只猪均进行120、100及80 kV管电压并分别作为A、B、C组。前瞻性心电门控冠状动脉256层螺旋CT扫描,并将原始数据进行FBP、iDose^4及IMR重建算法,比较各组重建图像客观指标(包括噪声、信噪比、对比噪声比及左主干开口处主动脉CT值),并对图像质量进行主观评分。结果不同管电压条件下IMR重建较iDose^4、FBP重建噪声小(P <0.05),iDose^4较FBP噪声大(P <0.05);不同重建方法同一组内主观评分比较,差异有统计学意义(P <0.05),且80 kV条件下IMR重建图像噪声较120 kV条件下的iDose^4、FBP低(P <0.05)。C组辐射剂量仅为A组的33.68%。结论在冠状动脉CT成像中,IMR较iDose^4和FBP显著提高图像质量,用80 kV低电压扫描结合IMR重建方法既降低了辐射剂量,又提高了图像质量。
Objective To investigate the performance of a knowledge-based iterative reconstruction(iterative model reconstruction-IMR) compared to filtered back projection(FBP) and a hybrid iterative reconstruction technique(iDose^4) in coronary CT angiography under different tube voltages. Methods Five miniature pigs underwent prospective axial ECG-gated coronary 256-slice spiral CT angiography at different tube voltages including 120, 100 and 80 kV(group A, B and C). All original data were reconstructed using the FBP, iDose^4 and IMR algorithms. The objective indices of the reconstructed images, including image noise, signal-to-noise ratio(SNR), contrast-to-noise ratio(CNR), and mean CT value of the aortic root were compared among the three groups reconstructed by the different algorithms. A 5-point scale was used to assess subjective image quality of coronary segments and images with a score of ≥ 4 as a good criterion. Results At all three tube voltages, the IMR algorithm consistently yielded a lower noise and a higher CNR than iDose^4 and FBP(P < 0.05). The differences of subjective scores among different reconstruction methods in the same group were all statistically significant(P < 0.05). In addition, at 80 kv, the image noise in IMR reconstruction was lower than in iDose^4 and FBP reconstructions at 120 kV(P < 0.05);the radiation dose in group C was only 33.68% of that in group A. Conclusions Compared to iDose^4 and FBP algorithms, iterative model reconstruction(IMR) algorithm significantly improves the image quality of 256-slice coronary CT angiography. A combination of low tube voltage(80 kV) and IMR algorithm can help reduce radiation dose and improve image quality.
作者
蒋骏
雷益
温红
林一钦
黄美萍
陈子满
Jun Jiang;Yi Lei;Hong Wen;Yi-qin Lin;Mei-ping Huang;Zi-man Chen(Department of Radiology,Shenzhen Second People’s Hospital,Shenzhen,Guangdong 518000,China;Department of Medical Imaging,Huizhou Municipal Central Hospital,Huizhou,Guangdong 516000,China;Cardiac Catheterization Laboratory,Guangdong General Hospital,Guangzhou,Guangdong 510030,China;Department of Ultrasound,The Fifth Affiliated Hospital Sun Yat-Sen University,Zhuhai,Guangdong 519000,China)
出处
《中国现代医学杂志》
CAS
2020年第2期6-13,共8页
China Journal of Modern Medicine
