As such some of what we see is just the brains interpretation of sensations from the eye structure and the pressure applied to it. Try rubbing your closed eyes and you will see what I mean. Always remember that the number one job of the brain is pattern recognition.
Emphysema is a form of chronic (long-term) lung disease, usually caused by smoking. Because of lung damage, people with emphysema have difficulty blowing air out. The major symptom of emphysema is shortness of breath.
Cigarette smoke also causes inflammation and irritation in the lungs leading to an increase in mucus production. Too much mucus in the lungs places you at an increased risk for lung infections, as mucus provides bacteria with the perfect hide-away. Air pollution also plays a role in the development of emphysema.