Emphysema is a serious lung condition typically associated with risk factors such as smoking, and it is categorized under Chronic Obstructive Pulmonary Disease (COPD). In emphysema, the small air sacs in the lungs, called alveoli, are gradually damaged and lose their function. This damage results in a loss of elasticity in the lung tissue, leading to breathing difficulties, particularly shortness of breath.

Lung tissue consists of airways, which transport inhaled air to the gas exchange regions, and the parenchyma (alveoli), where oxygen-carbon dioxide exchange occurs. Chronic inflammation of the airways is known as chronic bronchitis. In the advanced stages of chronic bronchitis, emphysema develops due to the destruction of the alveoli responsible for gas exchange. These two conditions (chronic bronchitis and emphysema) often occur together or sequentially, forming different stages of COPD.

The most prominent symptom of emphysema is shortness of breath. In addition to shortness of breath, coughing and wheezing are also among the commonly observed symptoms in patients with emphysema.