and visceral pleura. lung volume reduction lung volume reduction may be offered to those with advanced emphysema. when other treatments fail, and the emphysema is located in the upper lobes, a surgical option may be possible. a number of minimally invasive bronchoscopic procedures are increasingly used to reduce lung volume. surgical where there is severe emphysema with significant hyperinflation that has proved unresponsive to other therapies, lung volume reduction surgery (lvrs) may be an option. lvrs involves the removal of tissue from the lobe most damaged by emphysema, which allows the other lobes to expand and give improved function. the procedure appears to be particularly effective if the emphysema primarily involves the upper lobes; however, the procedure increases the risk of adverse events and early death in people who have diffuse emphysema. bronchoscopic minimally invasive bronchoscopic procedures may be carried out to reduce lung volume. these include the use of valves, coils, or thermal ablation. endobronchial valves are one-way valves that may be used in those with severe hyperinflation resulting from advanced emphysema; a suitable target lobe and no collateral ventilation are required for this procedure. the placement of one or more valves in the lobe induces a partial collapse of the lobe that ensures a reduction in residual volume that improves lung function, the capacity for exercise, and quality of life. the placement of endobronchial coils made of nitinol, instead of valves is recommended where there is collateral ventilation that would prevent the use of valves. nitinol is a biocompatible shape-memory alloy. both of these techniques are associated with adverse effects, including persistent air leaks and cardiovascular complications. bronchoscopic thermal vapor ablation has an improved profile. heated water vapor is used to target affected lobe regions, which leads to permanent fibrosis and volume reduction. the procedure is able to target individual lobe segments, can be carried out regardless of collateral ventilation, and can be repeated with the natural advance of emphysema. other surgeries lung transplantation – the replacement of either a single lung or both (bilateral) – may be considered in end-stage disease. a bilateral transplant is the preferred choice as complications can arise in a remaining single native lung; complications can include hyperinflation, pneumonia, and the development of lung cancer. careful selection as recommended by the national emphysema treatment trial (nett) for transplant surgeries is needed as in some cases there will be an increased risk of mortality. 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. in other tissues trapped air can also develop in other tissues such as under the skin, known as subcutaneous emphysema. orbital emphysema is the trapping of air in the orbit; a type of this is palpebral emphysema that affects just the eyelids. history giovanni battista morgagni, who recorded one of the earliest descriptions of emphysema in 1769 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. these were followed the illustrations of matthew baillie in 1789 and descriptions of the destructive nature of the condition.