多模型迭代重建算法对成人腹部不同实质脏器CT图像质量的影响

Research of ASiR-V on image quality influence of CT with different adult abdominal parenchyma organs

目的探讨多模型迭代重建算法(ASiR-V)不同迭代重建级别对成人腹部不同实质脏器CT图像质量的影响以及最佳重建级别。方法选取体质量指数(BMI)18.5~24.9 kg/m2、需要行腹部CT平扫的成人患者80例,进行常规腹部CT平扫,分别采用5种不同重建级别(10%、30%、50%、70%、90%)对扫描图像进行重建,并对重建图像进行主观及客观评价。主观评价采用五分制。客观评价:分别测量肝、脾、胰腺、肾及竖脊肌CT值及CT值标准差(SD),并计算信噪比(SNR)、对比噪声比(CNR)。结果主观评价:肝及脾70%重建级别图像评分最高,胰腺50%及70%重建级别图像评分最高,肾50%重建级别图像评分最高。客观评价:随着ASiR-V重建级别提高,图像噪声SD值呈下降趋势,SNR及CNR值呈上升趋势,肝、脾、胰腺、肾不同重建级别的SD值、SNR值及CNR值差异均有统计学意义(P<0.05)。结论对于不同腹部实质脏器,肝及脾采用70%重建级别图像质量最佳,胰腺采用50%及70%重建级别图像质量最佳,肾采用50%重建级别图像质量最佳。

Objective To investigate the effect of different iterative reconstruction levels of multiple model adaptive statistical iterative reconstruction-V(ASiR-V)algorithm on the image quality of different parenchyma organs in adult ab-dominal CT and determine the optimal reconstruction level.Methods 80 adult patients with a body mass index(BMI)between 18.5 and 24.9 kg/m2,requiring abdominal CT scans,underwent routine abdominal CT scans.The scanned im-ages were reconstructed using five different reconstruction levels(10%,30%,50%,70%,90%),and the reconstructed images were evaluated subjectively and objectively.Subjective evaluation used a five-point scale.Objective evaluation included measuring CT values and standard deviation(SD)values of the liver,spleen,pancreas,kidneys,and erector spinae muscle,along with calculating signal-to-noise ratio(SNR)and contrast-to-noise ratio(CNR).Results Sub-jective evaluation:the 70%reconstruction level had the highest scores for liver and spleen images,the 50%and 70%re-construction levels had the highest scores for pancreas images,and the 50%reconstruction level had the highest scores for kidney images.Objective evaluation:as the reconstruction level of ASiR-V increased,the SD values of image noise de-creased,while the values of SNR and CNR increased.There were significant differences in SD,SNR,and CNR values a-mong different reconstruction levels of the liver,spleen,pancreas,and kidneys.Conclusions For different parenchyma organs in the abdomen,the 70%reconstruction level provides the best image quality for the liver and spleen,the 50%and 70%reconstruction levels provide the best image quality for the pancreas,and the 50%reconstruction level provides the best image quality for the kidneys.