慢性阻塞性肺病的CT肺功能研究

Evaluation of chronic obstructive pulmonary disease using quantitative CT pulmonary function

目的:研究平静呼吸状态下定量CT肺功能对慢性阻塞性肺病(COPD)的诊断价值。方法:COPD组48例和健康对照组28例,行平静呼吸下定量CT检查。利用CT肺功能定量分析软件分析图像数据并得出相应CT肺功能参数值:CT值(包括两肺平均CT值,左、右两肺CT值,上、中、下肺野CT值),像素指数(PI,分为-1024～-960,-960～-910,-910～-800,-800～-700,>-700五区),容积(两肺总容积,左右两肺各自容积),比较各组参数的差异。结果:轻中度组、重度组与正常组相比,肺总容积、PI-960～-910均显著增加,平均CT值、PI-800～-700、PI>-700均显著减低(P<0.01),PI-1024～-960、PI-910～-800在正常组、轻中度组及重度组之间均存在差异(P<0.05)。轻中度组及重度COPD组的CT值、各PI指数在左右两肺及上中下肺野之间比较差异均无显著性(P>0.05)。结论:定量CT肺功能可对不同程度COPD的肺功能进行评估,是对COPD患者尤其是不能耐受肺功能检查者了解其肺功能情况的另一种途径。

Objective： To assess the diagnostic value of chronic obstructive pulmonary disease （COPD） in normal respiration by quantitative CT pulmonary function. Methods： The studied population consisted of 48 patients with COPD and 28 normal volunteers as controls. The CT source images of each case were analyzed with CT pulmonary quantitative software and the parameters included the mean attenuation value, the attenuation value of each lung field （include upper, middle and lower field）, pixel indices （Pl with five groups of -I024～-960, -960～-910, -910～-800,-800～-700, 〉-700）, lung volume （total lung volume and volume of each lung）. Results： As compared with control group, total lung volume and PI（-960～-940）significantly increased in slight-moderate group and severe group, while the mean attenuation value, PI（-600～-700）and PI （〉-700） were significantly decreased （P〈0.01）. There was statistically difference in PI（-1024～-960） and PI （-910～-800） among three groups （P〈0.01）. No significant difference was found in the attenuation value between groups, and there was no statistical difference in PI between left and right lung field （include upper, middle and lower field） in slight-moderate group and severe group （P〉0.05）. Conclusion： Patients with COPD can be evaluated by quantitative cr pulmonary function and served as an alternative tool for those patients who could not be assessed by pulmonary function test （PFT）.