What Is It?
Emphysema is a respiratory disease. In this condition, millions of the lungs' tiny air sacs (alveoli) stretch out of shape or rupture. As these thin, fragile air sacs become damaged or destroyed, the lungs lose their natural elasticity. Air stays trapped inside the lungs because the damaged lung sacs can't empty.
Emphysema is a progressive disease, which means it continues to get worse. As the condition progresses, the lungs lose their ability to absorb oxygen and release carbon dioxide. Breathing becomes more difficult. A person feels easily short of breath, like he or she is not getting enough air.