em·phy·se·ma (ĕm′fĭ-sēmə, -zē-)
1. A pathological condition of the lungs marked by an abnormal increase in the size of the air spaces, resulting in labored breathing and an increased susceptibility to infection. It can be caused by irreversible expansion of the alveoli or by the destruction of alveolar walls.
2. An abnormal distension of body tissues caused by retention of air.
[Greek emphūsēma, inflation, from emphūsān, to blow in : en-, in; see EN-2 + phūsān, to blow (from phūsa, bellows, bladder).]
em′phy·sema·tous (-sĕmə-təs, -sēmə-, -zĕmə-, -zēmə-) adj.
em′phy·semic adj. & n.
(click for a larger image)emphysema
top: normal bronchiole and alveoli
bottom: diseased bronchiole with mucus, enlarged air sacs in the alveoli, and fewer capillaries
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