Emphysema

Emphysema is a type of chronic obstructive pulmonary disease (COPD), a condition that limits the flow of air when you breathe out. Emphysema occurs when the air sacs at the ends of your smallest air passages (bronchioles) are gradually destroyed. It is often caused by exposure to toxic chemicals, including long-term exposure to tobacco smoke.

As it worsens, emphysema turns the spherical air sacs - clustered like bunches of grapes - into large, irregular pockets with gaping holes in their inner walls. This reduces the number of air sacs and keeps some of the oxygen entering your lungs from reaching your bloodstream. In addition, the elastic fibers that hold open the small airways leading to the air sacs are slowly destroyed, so that they collapse when you breathe out, not letting the air in your lungs escape.

If you smoke, quitting can help prevent you from getting the disease. If you already have emphysema, not smoking might keep it from getting worse. Treatment is based on whether the symptoms are mild, moderate or severe. Treatments include inhalers, oxygen, medications and sometimes surgery to relieve symptoms and prevent complications.