Description of Bullous Emphysema Using Lung Ultrasound and Comparison to the Characteristics of Pneumothorax

Chronic Obstructive Pulmonary Disease (COPD) is a frequent disease affecting a growing number of adults in the world which is responsible for a large public health burden through heavy morbidity and mortality. Emphysema is one of a wide spectrum of pulmonary complications linked to COPD, defined as the abnormal permanent enlargement of the airspaces distal to the terminal bronchioles accompanied by destruction of the alveolar wall. Disease progression is correlated to worsening and enlargement of emphysema lesions, sometimes conflating in sizeable bullae, deleterious to normal mechanical pulmonary function. Bullous emphysema (BE) is sometimes eligible to invasive curative treatment through surgery or interventional bronchoscopy. Diagnosis of BE relies on computerized tomodensitometry (CT), the gold-standard for evaluating pulmonary parenchyma. However, CT is not always available, and bullous emphysema can present as pneumothorax on chest radiography. The practice of lung ultrasound is currently growing in respiratory medicine and emergency departments owing to an increasing amount of evidence showcasing its reliability as a diagnostic tool, most notably for pneumothorax and other pleural diseases. Despite BE having been reported to present similarly to pneumothorax in ultrasound, its characteristics have not yet been precisely described. The primary aim of this study is to describe BE using lung ultrasound. Participants with known BE on CT will undergo a simple ultrasound examination. The secondary aim is to compare the characteristics of BE to those of pneumothorax using lung ultrasound. To achieve this, a second group of participants with currently treated pneumothorax will also undergo lung ultrasound.