Emphysema: is a lung condition featuring an abnormal accumulation of air due to enlargement and destruction of the lung's many tiny air sacs resulting in the formation of scar tissue. The destruction of the air sacs and formation of scar tissue is permanent and the disease is incurable, however medication may be helpful to ease symptoms. Emphysema is strongly associated with smoking cigarettes. The best response to the early warning signs of emphysema is to stop smoking.