Registration-based metrics of lung function to describe copd: The ultimate question of life, the universe, and everything

摘要

We have a very complex organ (the lung), and on it is super imposed a very complicated disease, chronic obstructive pulmonary disease (COPD). How can we devise a simple value that gives us greater insight into this heterogeneous disease in this complex organ? How can we better assess COPD in patients? More important, how can we better determine the extent that ever-worsening COPD has on the lives of our patients? The pulmonary component of COPD is characterized by airflow limitation that is not fully reversible. The airflow limitation is usually progressive and associated with an abnormal inflammatory response of the lungs to noxious particles or gases (1), the most common of which is cigarette smoke. COPD is classically assessed by pulmonary function testing. Spirometry is a pulmonary function test (PFT) to determine the diagnosis and evaluate the severity of the disease. The ratio of the post-bronchodilator forced expiratory volume in 1 second divided by the forced vital capacity (FEV_1/FVC) <0.70 is the classic cut-off for a diagnosis of COPD (1). As the FEV_1/FVC ratio decreases, the severity of the disease increases. The generally accepted categorization of COPD severity classifies patients into four stages according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) classification (1). Can we devise a better way to assess the disease based on the directly viewed changes in the lungs in vivo?