Assessment of Pulmonary EmphySema: the Clinical -ULtrasonographic APproach to chronIc Obstructive Pulmonary Disease

The use of lung ultrasound (LUS) is instrumental in the evaluation of many thoracic diseases and its ability to detect pleural-pulmonary pathologies is widely accepted. However, the use of LUS as an indication of underlying parenchymal lung disease, when the organ is still aerated, is a relatively new application. A-lines and B-lines are two separate and distinct artifacts which may be seen during the examination of the nonconsolidated lungs by ultrasound because of different underlying structures. Even though the practical role of LUS artifacts is accepted for detecting and monitoring many conditions, we do not fully understand their origin. The artifactual information beyond the pleura line in LUS images of the normal and of the not critically deflated lung represents the ultimate outcome of complex interactions of a specific acoustic wave with a specific three-dimensional structure of the biological tissue.

Chronic obstructive pulmonary disease (COPD) is a complex condition with a wide spectrum of clinical presentations and pathological features unified under the spirometric definition of airflow obstruction. The mechanisms responsible for airflow obstruction in COPD (airway narrowing and parenchymal destruction) cannot be distinguished by standard spirometry.

Chest computed tomography (CT) allows to depict and measure in vivo the lung pathologic changes of COPD by quantifying parenchymal destruction, the direct sign of emphysema. Although quantitative and qualitative studies have shown that CT can allow distinguishing subtypes of emphysema, a widespread routine use of CT for the assessment of COPD in clinical practice cannot be currently foreseen due to radiation exposure and limited instrumental availability.

LUS can detect pleural-pulmonary pathologies. However, the use of LUS as an indication of underlying parenchymal lung disease, when the organ is still aerated, as in emphysema, is a new application.

This study is aimed at researching correlations among a pool of data deriving from ultrasonographic and tomographic evaluations of patients with panlobular or paraseptal emphysema, to improve the comprehension of acoustic information derived from ultrasound evaluation.