Related Experiment Video
Updated: Jan 1, 2026

Automated Measurement of Pulmonary Emphysema and Small Airway Remodeling in Cigarette Smoke-exposed Mice
Published on: January 16, 2015
Influence of Emphysema and Air Trapping Heterogeneity on Pulmonary Function in Patients with COPD
Kun Li1, Yanli Gao1, Zhenyu Pan1
1Department of Radiology, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, Republic of China.
Purpose:
To explore the influence of emphysema and air trapping heterogeneity on pulmonary function changes in patients with stable chronic obstructive pulmonary disease (COPD).
Patients And Methods:
One hundred and seventy-nine patients with stable COPD were enrolled in this prospective study. All patients underwent low-dose inspiratory and expiratory CT scanning and pulmonary-function tests. CT quantitative data for the emphysema index (EI) on full-inspiration and air trapping (AT) on full-expiration were measured for the whole lung, the right and left lungs, and the cranial-caudal lung zones. The heterogeneity index (HI) values for emphysema and air trapping were determined as the ratio of the difference to the sum of the respective indexes. The cranial-caudal HI and left-right lung HI were compared between mild-to-moderate (GOLD stage I and II) and severe (GOLD stage III and IV) disease groups. The associations between HI and pulmonary-function measurements adjusted for age, sex, height, smoking history, EI and AT of the total lung were assessed using multiple linear regression analysis.
Results:
The absolute values for cranial-caudal HI (AT_CC_HI) and left-right lung HI (AT_LR_HI) on full-expiration were significantly larger in the mild-to-moderate group, while no significant intergroup differences were observed on full-inspiration. COPD patients with lower-zone and/or left-lung predominance showed significantly lower pulmonary function than those with upper-zone and/or right-lung predominance on full-expiration, whereas no significant differences were observed on full-inspiration. The absolute values of AT_CC_HI and AT_LR_HI significantly correlated with pulmonary-function measurements. Higher AT_CC_HI and lower AT_LR_HI absolute values indicated better pulmonary function, after adjusting for age, sex, height, smoking history, EI and AT of the total lung.
Conclusion:
Subjects with more heterogeneous distribution and/or upper-zone predominant and/or right-lung predominant patterns on full-expiration tend to have better pulmonary function. Thus, in comparison with emphysema heterogeneity, AT heterogeneity better reflects the pulmonary function changes in COPD patients.
More Related Videos
02:09Multi-modal Pulmonary Imaging: Using Complementary Information from CT and Hyperpolarized 129Xe MRI to Evaluate Lung Structure-Function
Published on: April 12, 2024
08:25Combining Volumetric Capnography And Barometric Plethysmography To Measure The Lung Structure-function Relationship
Published on: January 8, 2019
Related Concept Videos
Chronic Obstructive Pulmonary Disease
Smoking is a primary risk factor for COPD, with over 80% of patients having a history of it. Patients typically experience progressive dyspnea or labored breathing, frequent coughing, and recurrent pulmonary infections. Many eventually succumb to respiratory failure, characterized by...
Chronic Obstructive Pulmonary Disease-II: Pathophysiology
Chronic Inflammation
Chronic Obstructive Pulmonary Disease-I: Introduction
Factors Affecting Pulmonary Ventilation
Alveolar Surface Tension
The alveolar fluid lines the luminal surface of the alveoli and exerts a force called surface tension. This force is caused by the polar water molecules in the liquid being more strongly attracted to each...
Chronic Obstructive Pulmonary Disease-IV: Assessement and Diagnostic Studies
Medical History
COPD: Pathogenesis and Clinical Features
The primary cause for the onset of COPD is cigarette smoking and exposure to air pollution. These hazardous factors initiate a chain reaction within the lungs, resulting in chronic inflammation, damage to the airways, and a...