低剂量自适应迭代重建技术在颅面部联合外伤CT检查中应用

Application of low-dose adaptive iterative reconstruction technique in combined craniofacial trauma CT examinations

目的探讨低剂量自适应迭代重建技术在颅面部联合外伤CT检查中应用。方法选取2019年2月至2021年12月承德市中心医院收治的180例颅面部联合外伤病人,均行常规剂量CT扫描[常规组,最佳噪声指数(noise index,NI)结合30%自适应迭代重建],在复查CT(与初次扫描间隔<24 h)中按照随机数字表法将病人按照1∶1∶1均分为A组(n=60,NI25结合40%自适应迭代重建)、B组(n=60,NI30结合50%自适应迭代重建)、C组(n=60,NI35结合60%自适应迭代重建),均使用同一设备进行扫描。比较各组扫描时间、受检者剂量容积指数(CT dose index of volume,CTDIvol)、扫描长度(length,L)、剂量长度乘积(dose length product,DLP)、有效剂量(effective dose,ED)、对比信噪比(compare signal-to-noise ratio,CNR)、信噪比(signal-tonoise ratio,SNR)、图像质量主观评价效果。结果扫描时间:C组<A组和常规组<B组,两两比较均差异有统计学意义(P<0.05);CTDIvol、DLP、ED:常规组>A组>B组>C组,两两比较均差异有统计学意义(P<0.05);SNR:常规组>A组>B组>C组,两两比较均差异有统计学意义(P<0.05);A组(98.33%)、B组(96.67%)满意率与常规组(100.00%)比较,差异无统计学意义(P>0.008);C组满意率(88.33%)低于常规组(100.00%)(P<0.008)。结论CT扫描中,NI30结合50%自适应迭代重建能满足高质量图像和低辐射剂量的双重要求,可作为颅面部联合外伤的一个最佳诊断参数组合。

Objective To investigate the application of low-dose adaptive iterative reconstruction techniques in combined craniofacial trauma CT examinations.Methods A total of 180 patients with combined craniofacial trauma who were treated in Chengde Central Hospital from February 2019 to December 2021 were selected and underwent conventional dose CT scans[(conventional group,optimal noise index(NI)combined with 30%adaptive iterative reconstruction)],in the re-examination CT(with an interval of less than 24 h from the initial scan),the patients were equally divided into group A(n=60,NI25 combined with 40%adaptive iterative reconstruction),group B(n=60,NI30 combined with 50%adaptive iterative reconstruction),group C(n=60,NI35 combined with 60%adaptive iterative reconstruction),all were scanned with the same equipment.The scan time,subject dose volume index(CTDIvol),scan length(L),dose length product(DLP),effective dose(ED),contrast signal-to-noise ratio(CNR),signal-to-noise ratio(SNR),subjective evaluation of image quality were compared.Results Scanning time:group C<group A and routine group<group B,the difference was statistically significant(P<0.05);CTDIvol,DLP,ED:routine group>group A>group B>group C,the difference between the two comparisons was statistically significant(P<0.05);SNR:conventional group>group A>group B>group C,the difference was statistically significant(P<0.05);Group A(98.33%),Compared with the conventional group(100.00%),the satisfaction rate of group B(96.67%)was not significantly different(P>0.008);the satisfaction rate of group C(88.33%)was lower than that of the conventional group(100.00%)(P<0.008).Conclusion In CT scanning,NI30 combined with 50%adaptive iterative reconstruction can meet the dual requirements of high quality image and low radiation dose,and can be used as an optimal combination of diagnostic parameters for craniofacial combined trauma.