不同自适应统计迭代重组水平对肺功能定量CT参数影响

目的探讨自适应统计迭代重组(ASIR)不同水平设定对于肺功能定量CT参数测定影响。方法搜集2016年2月至2016年3月28例吸烟患者,男20例,女8例;年龄(58.43±17.26)岁。高分辨率CT检查数据,间隔10%设定ASIR进行图像重组,利用机器自带肺功能软件进行定量分析,观察10%~90%ASIR水平肺内低密度区(<-950 HU)比例以及全肺体积变化。不同ASIR水平肺功能定量参数肺内低密度区占比(LAA%)、全肺体积(TLV)]间采用Friedman检验或单因素重复测量方差分析方法。P<0.05为差异具有统计学意义。结果ASIR水平对于LAA%结果具有明显影响,随着ASIR数值提高,LAA%呈下降趋势(χ^2=29.426,P<0.001)。不同ASIR水平之间TLV不存在明显统计学差异(F=1.046,P=0.325)。结论不同ASIR水平对于肺功能定量CT参数LAA%具有明显影响,在利用CT对小气道病变进行定量分析,或者不同研究中心数据进行对比时,需考虑到ASIR水平可能带来的影响。

The Effect of Adaptive Statistical Iterative Reconstruction Levels on Quantitative Analysis of Lung Function using MDCT

Objective The aim of the study was to investigate the influence of different ASiR levels on quantitative analysis of lung function using MDCT.Methods Twenty-eight smokers(20 male,8 female;age 58.43±17.26 y)who underwent chest high resolution CT were enrolled in the study.The raw data was reconstructed using different ASiR levels(interval 10%,range 10%~90%),then postprocessed on GE Advantage workstation and analyzed using in-house thoracic VCAR-parenchyma analysis software.The values of low attenuation area ratio(LAA%)and total lung volume(TLV)were recorded and compared among different ASiR levels constructed images using Friedman test or one-way repeated measures ANOVA analysis.Statistical significance was set at 5%.Results ASiR levels demonstrated significant influence on final LAA%results,which showed a downward trend with higher ASiR level(χ^2=29.426,P<0.001).However,the values of TLV showed no statistical differences among different ASiR levels constructed data(F=1.046,P=0.325).Conclusion The quantitative measurement of LAA%has been effectively influenced by ASiR level.Hence,care should be taken in ASiR level on assessment of small airways with CT data or comparison results from different research centers.