Contrast-enhanced CT is useful in assessing vascular abnormalities and mediastinal masses. Focal
Focal emphysema, is a localized region of emphysema in the lung that is larger than alveoli, and often associated with coalworkers pneumoconiosis. This is also known as localized pulmonary emphysema. Blebs and bullae may also be included as focal emphysema. These can be differentiated from the other type of enclosed air space known as a lung cyst by their size and wall thickness. A bleb or bulla  has a wall thickness of less than 1 mm, and are smaller. Occupational
A number of occupations are associated with the development of emphysema due to the inhalation of varied gases and particles. In the US uranium mining that releases radon gas and particles has been shown to be a cause of emphysema deaths; the figures in the study included some miners who also smoked. Uranium mining and milling was found to create environmental pollution.The inhalation of coal mine dust that can result in coalworkers pneumoconiosis is an independent risk factor for the development of emphysema. Focal emphysema is associated with the coal macule, and this extends into progressive centrilobular emphysema. Less commonly a variant of panlobular emphysema develops.Silicosis results from the inhalation of silica particles, and the formation of large silica nodules is associated with paracicatricial emphysema, with or without bullae. Ozone-induced emphysema
Ozone is another pollutant that can affect the respiratory system. Long-term exposure to ozone can result in emphysema. Osteoporosis
Osteoporosis is a major comorbidity of emphysema. Both conditions are associated with a low body mass index.
Several factors including age, and poor exercise tolerance, using the BODE index need to be taken into account. A transplant is only considered where there are no serious comorbidites. A CT scan or a ventilation/perfusion scan may be useful in surgery considerations to evaluate cases for surgical interventions, and also to evaluate post-surgery responses. A bullectomy may be carried out when a giant bulla occupies more than a third of a hemithorax. History
The terms emphysema, and chronic bronchitis were formally defined in 1959 at the CIBA guest symposium, and in 1962 at the American Thoracic Society Committee meeting on Diagnostic Standards. The word emphysema is derived from Ancient Greek ἐμφύσημα inflation, swelling (referring to a lung inflated by air-filled spaces), itself from ἐμφυσάω emphysao to blow in, to inflate, composed of ἐν en, meaning "in", and φυσᾶ physa, meaning "wind, blast".René Laennec, the physician who invented the stethoscope, used the term emphysema in his book A Treatise on the Diseases of the Chest and of Mediate Auscultation (1837) to describe lungs that did not collapse when he opened the chest during an autopsy. He noted that they did not collapse as usual because they were full of air and the airways were filled with mucus. Early descriptions of probable emphysema include: in 1679 by T. Bonet of a condition of "voluminous lungs" and in 1769 by Giovanni Morgagni of lungs which were "turgid particularly from air". In 1721 the first drawings of emphysema were made by Ruysh.