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.
Smoking cigarettes is by far the most common cause of emphysema. And emphysema is by far the most common cause of giant bullae in the lungs. There are limited cases of bullae appearing in the lungs as a result of bronchial illnesses from high air pollution levels, or occupational exposure to chemical fumes.