全模型实时自适应迭代重建技术在胸部扫描中的临床应用

Exploration on the clinical application of ASIR-V in chest scanning

目的:分析全模型实时自适应迭代重建(ASIR-V)技术在胸部CT检查中的应用价值,探索前置和后置ASIR-V权重的最优组合。方法:前瞻性选取80例行胸部CT检查的患者,采用随机数表法将其分为A组、B组、C组和D组,每组20例,A组、B组、C组和D组患者分别为前置30%、40%、50%、60%ASIR-V权重。图像重建中A组行后置30%100%ASIR-V权重重建,获得A3A10亚组;B组、C组和D组分别行后置40%100%、50%100%和60%100%权重重建,并分别获得B4B10、C5C10和D6D10亚组。比较各组容积CT剂量指数(CTDIvol)、剂量长度乘积(DLP),计算有效剂量(ED);评价4组图像肺实质与降主动脉CT值与噪声值(SD);对图像的主观评分值进行分析。结果:4组患者辐射剂量测量值CTDIvol、DLP和ED随前置ASIR-V权重增加而明显降低,差异有统计学意义(F=13.860,F=12.731,F=12.680;P<0.05)。A组、B组、C组和D组的各亚组间随后置ASIR-V权重增加,肺实质噪声值和降主噪声值逐渐降低,差异有统计学意义(FA亚组=9.477,F=19.541;FB亚组=5.784,F=48.784;FC亚组=4.504,F=10.046;FD亚组=4.504,F=10.046;P<0.05)。A组亚组中,A3A6主观评分值逐渐增高,A6A10主观评分值逐渐降低;B组、C组和D组中主观评分值较高的为B6、C7和D8,其中B6主观评分值最高。结论:在胸部扫描中前置40%联合后置60%ASIR-V权重重建,可明显降低辐射剂量获得较好图像质量。

Objective:To analyze the application value of Adaptive Statistical Interative Reconstruction-V(ASIR-V)in computed tomography(CT) examination on chest,and explore the optimal combination of pre-and post-ASIR-V weight.Methods:80 patients who underwent CT examination on chest were selected in perspective study,and they were divided into group A,group B,group C and group D according to random number method,with 20 cases in each group.The patients of group A,group B,group C and group D were 30%,40%,50% and 60% pre-ASIR-V weight,respectively.In image reconstruction,group A underwent reconstruction of 30%-100% post-ASIR-V weight,and it obtained A3-A10 subgroup.And group B,group C and group D respectively underwent 40%-100%,50%-100% and60%-100% post ASIR-V weight for reconstruction,and the corresponding B4-B10 subgroup,C5-C10 subgroup and D6-D10 subgroup were respectively obtained.And the volume CT dose index(CTDIvol) and dose length product(DLP)of various groups were compared,and the effective doses(ED) of these four groups were compared.CT values and noise values(SD) of lung parenchyma and descending aorta in images of 4 groups were evaluated,and the subjective scoring values of the images were further analyzed.Results:The CTDIvol DLP and ED of measurement value of radiation dose of 4 groups significantly decreased with the increasing of pre-ASIR-V weight,and the differences of them among 4 groups were significant(F=13.860,F=12.731,F=12.680,P<0.05).The noise values of lung parenchyma and descending aorta gradually decreased with the increasing of post-ASIR-V weight of each subgroup of group A,group B,group C and group D,and the differences of them among these subgroups were significant(FAsybgroup=9.477,F=19.541;FBsubgroup=5.784,F=48.784;FCsubgroup=4.504,F=10.046;FDsubgroup=4.504,F=10.046,P<0.05).In each subgroup of group A,the subjective scores of A3 to A6 were gradually increasing,and the scores of A6 to A10 were gradually decreasing.The scores of B6,C7 and D8 were higher in group B,group C and group D,respectively,and the subjective score of B6 were highest among them.Conclusion:In the chest scan,the reconstruction of the combination of 40% pre-ASIR-V weight and 60% post-ASIR-V weight reconstruction can significantly reduce the radiation dose and obtain better image quality.