论文部分内容阅读
目的 评价混合迭代重建算法混合权重对肺CT量化分析结果的影响,包括图像噪声、肺实质及气道量化指标、肺结节体积等.方法 52例肺CT扫描原始数据分别利用滤波反投影(FBP)、ASIR-V30％、ASIR-V50％、ASIR-V70％、ASIR-V100％算法重建.测量肺气肿指数、全肺容积、右肺上叶尖段支气管气道腔面积、气道壁面积、气道壁面积百分比、气道壁平均厚度、气道平均直径、气管分叉层面气道内空气及降主动脉血液CT平均值、标准差.测量54枚肺结节实性及非实性体积.比较不同迭代混合权重对上述测量结果的影响.结果 随着ASIR-V比例的提高(FBP,ASIR-V30％,ASIR-V50％,ASIR-V70％,ASIR-V100％),肺气肿指数逐渐降低(分别为3.34％、2.13％、1.46％、0.98％、0.57％),图像噪声逐渐降低(空气CT值标准差:29.8 HU,25.5 HU,22.6 HU,19.6 HU,15.2 HU;降主动脉CT值标准差:35.2 HU,27.6 HU,22.7 HU,18.0 HU,12.1 HU)(P＜0.01),其他量化结果影响无统计学意义.结论 混合迭代重建混合权重影响肺CT图像噪声水平及肺气肿指数,对肺实质、气道指标、肺结节体积影响无统计学意义.“,”Objective This study aimed to investigate the impact of hybrid iterative reconstruction blending percentage on quantitative analysis of pulmonary CT.Methods Pulmonary CT images were acquired from 52 subjects and reconstructed using different hybrid iterative reconstruction blending percentage including FBP,ASIR-V30％,ASIR-V50％,ASIRV70％ and ASIR-V100％.Quantitative analyses were compared among the five algorithms including emphysema index (EI),total lung volume,luminal area,wall area,wall thickness,diameter of airway and nodule volume.CT value,nodule volume and standard deviation (SD) were also measured and compared.Results EIs were found statistically different FBP (3.34 ％),ASIR-V30％ (2.13 ％),ASIR-V50％ (1.46％),ASIR-V70％ (0.98％)andASIR-V100％ (0.57 ％) (P =0.000).SDs decreased dramatically in the order of increasing ASIR-V percentage air in trachea:FBP (29.8 HU),ASIR-V30％ (25.5 HU),ASIR-V50％ (22.6 HU),ASIR-V70％ (19.6 HU),ASIR-V100％ (15.2 HU),descending aorta:FBP (35.2HU),ASIR-V30％ (27.6HU),ASIR-V50％ (22.7HU),ASIR-V70％ (18.0HU),ASIRV100％ (12.1HU) (P =0.000).There was no statistically significant difference in CT values,airway dimensions,nodule volumes and lung volumes among the different algorithms.Conclusion With increasing blending percentage of ASIR-V,EIs and SDs decreased significantly,while volumetric quantification of lung nodule and airway dimensions were not affected with statistically significant difference.