【摘要】 目的:探讨"双低"(低对比剂、低管电压)技术结合多模型的迭代重建(ASiR-V)算法在肾脏双期CT增强扫描中的应用价值。方法:前瞻性选取临床因病情需要做肾脏CT增强检查的患者60例为研究对象,随机分成常规剂量组及低剂量组各30例。患者均行肾脏双期CT增强扫描。常规剂量组:管电压120 kVp,对比剂320 mgI/ml碘佛醇,使用传统滤波反投影法(FBP)技术进行图像重建;低剂量组:管电压100 kVp,对比剂270 mgI/ml碘克沙醇,使用多模型迭代重建算法(ASiR-V),分别记录两组患者的CT扫描有效辐射剂量(ED)及碘摄入量,比较两组患者行肾脏CT平扫及动脉期的肾皮质及髓质的CT值、图像噪声(SD),对比噪声比(CNR)及信噪比(SNR)。由两位高年资影像诊断医师进行主观图像评分;并对两组图像质量的客观评价和主观评价进行相关统计学分析。结果:低剂量组的ED及碘摄入量明显低于常规剂量组,差异具有统计学意义(P<0.05)。两组图像质量的客观评价(CT值、SNR、CNR及SD)及主观评分差异均无统计学意义(均P>0.05),两位医师对图像质量主观评分的一致性较好(Kappa=0.765)。结论:"双低"技术结合ASiR-V算法在肾脏双期CT增强扫描中可获得满足临床诊断要求的图像质量,并且可以明显降低患者的有效辐射剂量及碘摄入量,值得临床推广使用。更多还原

【Abstract】 Objective To explore the application value of “double low”(low contrast agent, low tube voltage)technique combined with multi-model iterative reconstruction(ASiR-V)algorithm in renal two-stage CT enhancement scanning.Method A prospective selection of our clinical needs for kidney CT enhancement examination of 60 patients, the group was randomly divided into conventional dose group(n=30)and low dose group(n=30).Both renal CT enhancement scans were performed.Routine dosage group: tube voltage 120 kvp, contrast agent 320 mgI/ml iodophorol, using traditional filter back projection(FBP)technology for image reconstruction; low dose group: tube voltage 100 kvp, contrast agent 270 mgI/ml iodixanol, multi-model iterative reconstruction algorithm(ASiR-V),CT scan effective radiation dose(ED)and iodine intake were recorded in both groups, the CT value, image noise(SD),contrast noise ratio(CNR)and signal-to-noise ratio(SNR)of renal cortex and medulla were compared between the two groups.The subjective image score was carried out by two senior image diagnostics, and the objective evaluation and subjective evaluation of the two groups were statistically analyzed.Results The ED and iodine intake of low dose group were significantly lower than that of conventional dose group(P<0.05).There was no significant difference in objective evaluation(CT value, SNR、CNR and SD)and subjective score between the two groups(all P>0.05),both doctors had better agreement on subjective score of image quality(Kappa=0.765).Conclusion The double low technology combined with the ASiR-V algorithm can obtain the image quality which meets the diagnostic requirements in the dual phase CT enhancement scan of the kidney, and can obviously reduce the radiation dose and iodine intake of the patients, which is worthy of clinical application.更多还原