emphysema (em-fi-se´ma)

1. Presence of air in the interstices of the connective tissue of a part. 2. A condition of the lung characterized by increase beyond the normal in the size of air spaces distal to the terminal bronchiole (those parts containing alveoli), with destructive changes in their walls and reduction in their number. Clinical manifestation is undue breathlessness on exertion, due to the combined effect (in varying degrees) of reduction of alveolar surface for gas exchange, ventilation-perfusion imbalance, and collapse of smaller airways with trapping of alveolar gas occurring predominantly in expiration; this causes the chest to be held in the position of inspiration ("barrel chest"), with prolonged expiration and increased residual volume; symptoms of chronic bronchitis often, but not necessarily, coexist. Two structural varieties are described: panlobular e. and centrilobular e.pulmonary e; [G. inflation of stomach, etc. fr. en, in, + physema, a blowing, fr. physa, bellows]
alveolar duct e. e. in which the primary involvement is in the alveolar ducts and respiratory bronchioles, as opposed to panacinar e.
bullous e. e. in which the enlarged airspaces are one to several cm in diameter, often visible on chest radiographs. Thin-walled air sacs under tension compress pulmonary tissue, either single or multiple. Sometimes amenable to surgical resection with improvement in pulmonary function.
centri-acinar e. centrilobular e
centrilobular e. e. affecting the lobules around their central bronchioles, causally related to bronchiolitis, and seen in coal-miner's pneumoconiosis.centri-acinar e;
compensating e. , compensatory e. increase in the air capacity of a portion of the lung when another portion is consolidated, shrunken, or unable to perform its respiratory function; the alveoli are distended, but there is no destruction of alveolar walls, and hence, no true e., as this term is now defined.
congenital lobar e. common cause of neonatal respiratory distress which usually involves the left upper lobe.
cutaneous e. subcutaneous e
diffuse e. panlobular e
diffuse obstructive e. the major component of chronic obstructive lung disease.
ectatic e. obstructive airway disease with areas of dilatation of alveoli acini. Seen primarily in association with inherited deficiency of alpha-1 protease inhibitor. See panlobular e.
familial e. e. inherited in association with severe a-1 antitrypsin deficiency. It may occur as an isolated feature [MIM*130700, 130710] or with cutis laxa and hemolytic anemia [MIM*225360].
gangrenous e. gas gangrene
generalized e. panlobular e
increased markings e. a term applied to mixed obstructive lung disease in which radiographic findings of emphysema coexist with nonvascular shadows, probably related to bronchial inflammation.
interlobular e. interstitial e. in the connective tissue septa between the pulmonary lobules.
interstitial e. 1. presence of air in the pulmonary tissues consequent upon rupture of the air cells; 2. presence of air or gas in the connective tissue.
intestinal e. pneumatosis cystoides intestinalis
irregular e. e. that shows no consistent relationship to any portion of the acinus; always associated with fibrosis.
mediastinal e. deflection of air, usually from a ruptured emphysematous bleb in the lung, into the mediastinal tissue.
panacinar e. panlobular e
panlobular e. e. affecting all parts of the lobules, in part, or usually the whole, of the lungs, and usually associated with a1-antiprotease deficiency e.diffuse e., generalized e., panacinar e;
paraseptal e. e. involving the periphery of the pulmonary lobules.
pulmonary e. emphysema (2)
senile e. e. consequent upon the physiologic atrophy of old age.
subcutaneous e. the presence of air or gas in the subcutaneous tissues.aerodermectasia, cutaneous e., pneumoderma, pneumohypoderma;
subgaleal e. collection of air or gas between the inner layer of the scalp and the cranium.
surgical e. subcutaneous e. from air trapped in the tissues by an operation or injury.
unilateral lobar e. a state in which the roentgenographic density of one lung (or one lobe) is markedly less than the density of the other(s) because of the presence of air trapped during expiration.Macleod's syndrome, Swyer-James syndrome (1);


Browse Medical References:

[A] [B] [C] [D] [E] [F] [G] [H] [I] [J] [K] [L] [M]
[N] [O] [P] [Q] [R] [S] [T] [U] [V] [W] [X] [Y] [Z]