低辐射剂量联合SAFIRE迭代算法应用于甲状腺CT增强扫描的可行性分析

Feasibility analysis about the low radiation dose combined with SAFIRE applying on thyroid CT enhancement scan

目的探究低辐射剂量联合正弦图确定迭代重建技术(SAFIRE)应用于甲状腺CT增强扫描中的可行性。方法选择300例行甲状腺CT检查患者,根据辐射剂量及重建方法的不同将其分为三组:A组(120 kv、180 mA、滤波反投影法重建)、B组(100 kv、100 mA、SAFIRE技术重建)、C组(100 kv、100 mA、滤波反投影法重建)。比较三组甲状腺CT值、信噪比(SNR)、对比信噪比(CNR)、容积剂量指数(CTDIvoll)、有效剂量长度乘积(DLP)、有效剂量(ED)、成像质量评分及对甲状腺疾病的诊断效能。结果B、C组甲状腺CT值、背景噪声、背景信号均大于A组,差异均有统计学意义(t分别=8.75、10.88、7.02;7.02、16.51、6.78,P均<0.05),CTDIvoll、DLP、ED值均小于A组,差异均有统计学意义(t分别=43.01、98.87、92.18;43.01、96.73、90.21,P均<0.05);B组图像质量评分高于A组和C组,差异均有统计学意义(t分别=6.68、4.31、7.44、4.32,P均<0.05)。三组扫描方法诊断甲状原疾病的灵敏度、特异度及准确度比较,差异均无统计学意义(χ^(2)分别=0.48、1.14、1.46,P均>0.05)。结论在甲状腺检查时,应用低辐射剂量联合SAFIRE技术进行CT增强扫描,可在降低辐射剂量的同时,保证图像质量。

Objective To explore the feasibility of low radiation dose combined with sinogram affirmed iterative recon-struction(SAFIRE)applying on thyroid CT enhancement scan.Methods A total of 300 patients who underwent thyroid CT examination were enrolled as the research objects.According to different radiation dose and reconstruction method,they were divided into group A(120kv,180mA,reconstruction with filtered back projection),group B(100kv,100mA,SAFIRE)and group C(100kv,100mA,reconstruction with filtered back projection).The thyroid CT value,signal to noise ratio(SNR),contrast noise ratio(CNR),CT dose index volume(CTDIvoll),dose-length product(DLP),effective radia-tion dose(ED),score of imaging quality and diagnostic efficiency of thyroid diseases were compared among the three groups.Results The CT value,background noise and background signal in group B and group C were greater than those in group A(t=8.75,10.88,7.02;7.02,16.51,6.78,P<0.05),while CTDIvoll,DLP,and ED were lower than those in group A(t=43.01,98.87,92.18,43.01,96.73,90.21,P<0.05).The score of image quality in group B was higher than that in group A and group C(t=6.68,4.31,7.44,4.32,P<0.05).There was no significant diference in the sensitivity,spe-cificity and accuracy of the three scanning methods in the diagnosis of thyroid disease(χ^(2)=0.48,1.14,1.46,P>0.05).Conclusion In thyroid examination,the application of low radiation dose combined with SAFIRE in CT enhancement scan can ensure images quality while reducing radiation dose.