摘要
目的:探讨自适应统计迭代重建(ASIR)技术对成人肝脏CT增强扫描的门静脉成像质量的影响。方法:2015年3月-2015年12月的68例受试者在64排128层螺旋CT上行肝脏CT增强检查。图像重建分别采用FBP和100%ASIR两种方法。由2名高年资影像诊断医师采用双盲法分别对FBP和ASIR重建出的肝脏门静脉期VR图像进行主观评价。分别手工记录肝实质、门静脉的CT值。计算门静脉对比噪声比(CNR)。对于图像质量的主观分析采用非参数Wilcoxon符号秩和检验方法,对于分析所需时间及CNR的比较采用配对t检验方法。结果:对肝脏增强CT门静脉期VR图像的主观评分,FBP为1.81±0.64,ASIR为2.50±0.83(P<0.05)。两种方法的门静脉CT值及肝实质CT值间差异没有统计学意义(P>0.05)。两种方法背景噪声间差异具有统计学意义(FBP为18.4±2.5,ASIR为6.9±2.3,P<0.05)。ASIR重建的图像的CNR高于FBP重建的图像(分别为5.56±1.91、1.99±0.51)(P<0.05)。结论:ASIR技术可以有效提高肝脏增强CT检查门静脉成像的CNR及图像质量。
Objective：To investigate the effect of adaptive statistical iterative reconstruction （ASIR） technique on the image quality of CT porto--venography in adults. Methods：From March to December 2015,68 patients had routine enhanced CT of liver on a multi-slice spiral CT equipment. Images were reconstructed with FBP and 100% ASIR techniques respec- tively, and were subjectively evaluated by two senior radiologists double-blindly. The mean CT value of liver parenchyma and portal vein were recorded manually. The contrast-to-noise ratio （CNR） of portal vein relative to liver parenchyma was calcu- lated. Wilcoxon signed rank test was used for statistical analysis of subjective rating. Paired t test was used to analyze the time required and CNR. Results：The subjective rating of VR-enhanced CT images of hepatic portal vein was 1.81 ± 0.64 for FBP,2. 50±0.83 for ASIR （P〈0.05）. No significant statistic difference was existed of CT value of portal vein and hepatic parenchyma （P〉0.05）. Yet there was significant difference between the two techniques in terms of background image noise （FBP：18.4±2.5,ASIR：6.9±2.3,P〈0. 05）. The CNR of the reconstructed image using ASIR （5.56±1.91） was higher than that using FBP （1.99±0.51） （P〈0.05）. Conclusion：The CNR and image quality of enhanced CT portovenography was higher on the reconstructed images with ASIR technique.
出处
《放射学实践》
北大核心
2017年第3期258-261,共4页
Radiologic Practice
