A section of a deceased person's lung that shows severe emphysema. The black "bubbles" are emphysemous alveoli that have expanded and become filed with black carbon that is from smoking

A thoracic X-ray of a person with emphysema. At the arrow in the left lung (right side of picture) can be seen a faint bubbly section that looks like a ghostly bunch of grapes. This is emphysema

This microscope image shows the very large expanded sections of lung tissue. These "holes" should be tiny and there should be thousands of them, instead of only hundreds

Emphysema is a disease of the lungs.

It is one of the diseases that make up chronic obstructive pulmonary disease (COPD). This is a set of diseases where the flow of air in the lungs is obstructed. Emphysema is most often caused by smoking but can be caused by other diseases or have no known cause at all.