vertebrobasilar insufficiency

insufficiency /in·suf·fi·cien·cy/ (-sah-fish´in-se) inability to perform properly an allotted function.

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adrenal insufficiency 

1. hypoadrenalism; abnormally diminished activity of the adrenal gland.

2. adrenocortical i.

adrenocortical insufficiency  abnormally diminished secretion of corticosteroids by the adrenal cortex, as in Addison's disease.

aortic insufficiency  defective functioning of the aortic valve, with incomplete closure resulting in aortic regurgitation.

cardiac insufficiency  heart failure.

coronary insufficiency  decrease in flow of blood through the coronary blood vessels.

insufficiency of the externi  deficient power in the externi muscles of the eye, resulting in esophoria.

ileocecal insufficiency  inability of the ileocecal valve to prevent backflow of contents from the cecum into the ileum.

insufficiency of the interni  deficient power in the interni muscles of the eye, resulting in exophoria.

mitral insufficiency  defective functioning of the mitral valve, with incomplete closure causing mitral regurgitation.

pulmonary insufficiency  defective functioning of the pulmonary valve, with incomplete closure causing pulmonic regurgitation.

thyroid insufficiency  hypothyroidism.

tricuspid insufficiency  defective functioning of the tricuspid valve, with incomplete closure causing tricuspid regurgitation; it is usually secondary to systolic overload.

valvular insufficiency 

1. dysfunction of a cardiac valve, with incomplete closure resulting in valvular regurgitation; named for the valve involved.

2. venous i.

velopharyngeal insufficiency  failure of velopharyngeal closure due to cleft palate, muscular dysfunction, etc., resulting in defective speech.

venous insufficiency  inadequacy of the venous valves with impairment of venous drainage, resulting in edema.

vertebrobasilar insufficiency  transient ischemia of the brain stem and cerebellum due to stenosis of the vertebral or basilar artery.

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vertebrobasilar insufficiency (verˈ·t·brō·bāˑ·z·ler inˈ·s·fiˑ·shn·sē),

n a disorder caused by decrease of blood flow in the vertebral or basilar arteries due to atherosclerosis or compression placed on the external wall of the arteries. Symptoms may include loss of vision, dizziness, or nausea. Also called
VBI, vertebrobasilar circulatory disorders, or
posterior circulation ischemia.