目的·探讨通过胸部CT计算得到的低衰减区比例（ratio of low attenuation areas，LAA%）及肺容积对评估肺通气功能受损程度的临床价值。方法·回顾性纳入2010年1月—2014年7月在上海交通大学医学院附属瑞金医院同期完成胸部CT和肺通气功能检查的患者，用Myrian软件自动计算LAA%及肺容积，与舒张后第1秒用力呼气容积（forced expiratory volume in 1 second，FEV1）及其占预计值百分比（FEV1%pred）进行相关性分析，并纳入患者性别、年龄、身高、体质量建立回归方程。绘制ROC曲线，比较LAA%、肺容积及回归方程所得值在判断肺通气功能受损程度中的价值，根据约登指数和特异度选取界值，验证诊断效能。结果·纳入1 150名受试者进入归纳组，LAA%与舒张后FEV1及FEV1%pred呈负相关，肺容积与舒张后FEV1呈正相关。舒张后FEV1的回归方程为：FEV1-2.700+0.111×肺容积-0.216×ln （LAA%+0.1） -0.025×年龄+0.154×性别+0.034×身高。舒张后FEV1%pred的回归方程为：FEV1%pred65.582+4.014×肺容积-7.508×ln （LAA%+0.1） -10.264×性别。在判断舒张后FEV1下降程度时，回归方程优于单独使用LAA%和肺容积；在判断舒张后FEV1%pred下降程度时，回归方程和LAA%优于肺容积。LAA%>1.61%用于判断舒张后FEV1%pred1的回归方程计算值1结论·得到了基于胸部CT所示肺容积和LAA%的舒张后FEV1及FEV1%pred的回归方程，LAA%与肺容积可以粗略地估计肺通气功能的受损程度。

Objective · To explore the clinical value of the ratio of low attenuation areas (LAA%) and lung volume calculated according to chest CT in evaluating the severity of spirometric abnormality. Methods · The patients who underwent chest CT scan and lung function test at the same time January 2010 to July 2014 in Ruijin Hospital, Shanghai Jiao Tong University School of Medicine were retrospectively enrolled. LAA% and lung volume were calculatedMyrian software. The correlation analysis was performed between post-bronchodiation forced expiratory volume in 1 second (FEV1) or its percentage of predicted value (FEV1%pred) and LAA% or lung volume. Multi-variable models for post-bronchodiation FEV1 and FEV1%pred were developed based on LAA%, lung volume, gender, height, and weight. The ROC curves were depicted and the diagnostic values of LAA%, lung volume, and models were compared. The cut points were chosen according to Younden indexes and specificity. Results · A total of 1 150 patients were included in summarization group. LAA% was negatively correlated with post-bronchodiation FEV1 and FEV1%pred. Lung volume was positively correlated with post-bronchodiation FEV1. The regression models of post-bronchodiation FEV1 and FEV1%pred were FEV1-2.700+0.111×lung volume-0.216×ln (LAA%+0.1)-0.025×age+0.154×gender+0.034×height and FEV1%pred65.582+4.014×lung volume-7.508×ln (LAA%+0.1)-10.264×gender, respectively. The regression model performed better than LAA% and lung volume in estimating the degree of post-bronchodiation FEV1 decrease. LAA% and the regression model performed better than lung volume in estimating the degree of post-bronchodiation FEV1%pred decrease. The sensitivity was 75.6% and the specificity was 90.6% in estimating post-bronchodiation FEV1%pred1.61% as the criteria. The sensitivity was 58.9% and the specificity was 81.4% in estimating post-bronchodiation FEV1Conclusion · The regression models of post-bronchodiation FEV1 and FEV1%pred were obtained based on lung volume and LAA% on chest CT. LAA% and lung volume can roughly estimate the severity of spirometric abnormality.