Bullous lung disease, or bullous emphysema, is a condition in which air pockets, or bullae, form in areas of the lung where there is severe tissue damage due to the emphysema, explains University of Rochester Medical Center. As the bullae grow larger, they occupy increasingly more space inside the patient's chest cavity, eventually causing enough pressure and crowding to diminish lung function dangerously. Another name for this condition is vanishing lung syndrome.
Once a bulla grows to the point of occupying at least one-third of the lung space, doctors call it a giant bulla, states University of Rochester Medical Center. Because a giant bulla places so much pressure on the affected lung, even areas that have not suffered damage from the emphysema can begin malfunctioning. Patients with smaller bullae do not usually experience symptoms beyond their typical emphysema complications, but giant bullae have distinct symptoms, including chest pressure, soreness, trouble breathing, fatigue from oxygen deprivation and a feeling of being bloated.
Emphysema is a condition in which the walls of pulmonary alveoli (the small air-filled sacs in the lungs) become less elastic, stretch and eventually rupture, forming larger sacs that don't work as efficiently and causing some air to remain trapped in the lungs. The vast majority of bullous lung cases occur in emphysema patients, although there are rare cases of people developing bullae due to high air pollution or exposure to chemical fumes on the job, notes University of Rochester Medical Center. Surgical removal of the bulla, called a bullectomy, is the most common treatment for this disease.