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Localized expansion and weakening of the wall of a vein.
See also: aneurysm
a sac formed by the localized dilatation of the wall of an artery, vein or the heart.
see aortic aneurysm.
an abnormal communication between an artery and a vein in which the blood flows directly into a neighboring vein or is carried into the vein by a connecting sac.
one arising as a result of weakening of the tunica media in severe atherosclerosis.
an infected aneurysm caused by bacteria.
a small saccular aneurysm of a cerebral artery, usually at the junction of vessels in the circle of Willis; such aneurysms frequently rupture, causing subarachnoid hemorrhage. Called also brain aneurysm.
thinning and dilatation of a portion of the wall of the left ventricle, usually a consequence of myocardial infarction.
dilatation and tortuous lengthening of part of an artery.
one in which some of the layers of the wall of the vessel are ruptured and some merely dilated. Called also mixed aneurysm.
observed sporadically in the aorta and pulmonary artery.
one resulting from hemorrhage that causes lengthwise splitting of the arterial wall, producing a tear in the inner wall (intima) and establishing communication with the lumen of the vessel; it usually affects the thoracic aorta. Seen most commonly in horses and caused by larvae of Strongylus vulgaris. See strongylosis. A specific disease of turkeys.
a spindle-shaped aneurysm.
one produced by growth of microorganisms (bacteria or fungi) in the vessel wall, or infection arising within a pre-existing arteriosclerotic aneurysm.
inherited aortic aneurysm
causes a high mortality rate in the affected cattle breed. The defect is in the abdominal aorta.
may result from the lodgement of pulmonary emboli; rupture and pulmonary hemorrhage are potential sequelae.
an infected aneurysm caused by fungi.
a saclike aneurysm.
one formed by rupture of an aneurysm into a vein. See also aneurysmal varix.
see venous dilatation.