| Term 
 | Definition 
 
        | a communication between two blood vessels without any intervening capillary network |  | 
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        | Term 
 | Definition 
 
        | permanent localized dilation of an artery, with an increase in diameter of 1.5 times its normal diameter |  | 
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 | Definition 
 
        | largest arterial structure in the body; arises from the left ventricle to supply blood to the head, upper and lower extremities, and abdominopelvic cavity |  | 
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 | Definition 
 
        | vascular structures that carry blood away from the heart |  | 
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 | Definition 
 
        | a disease of the arterial vessels marked by thickening, hardening, and loss of elasticity in the arterial walls |  | 
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 | Definition 
 
        | communication between an artery and a vein |  | 
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 | Definition 
 
        | condition in which the aortic wall becomes irregular from plaque formation |  | 
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 | Definition 
 
        | thrombosis of the hepatic veins |  | 
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 | Definition 
 
        | minute vessels that connect the arterial and venous systems |  | 
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        | Term 
 
        | cavernous transformation of the portal vein – |  | Definition 
 
        | periportal collateral channels in patients with chronic portal vein obstruction |  | 
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        | Term 
 | Definition 
 
        | arises from the celiac trunk to supply the liver |  | 
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        | Term 
 | Definition 
 
        | a division of the abdominal aorta at the level of the umbilicus that supplies blood to the lower extremities |  | 
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 | Definition 
 
        | weakening of the arterial wall |  | 
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        | Term 
 | Definition 
 
        | tear in the intima and/or media of the abdominal aorta |  | 
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        | Term 
 | Definition 
 
        | the sonographer selects the exact site to record Doppler signals and sets the sample volume (gate) at this site |  | 
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        | Term 
 | Definition 
 
        | circumferential enlargement of a vessel with tapering at both ends |  | 
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        | Term 
 
        | gastroduodenal artery (GDA) – |  | Definition 
 
        | branch of the common hepatic artery that supplies the stomach and duodenum |  | 
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        | Term 
 | Definition 
 
        | largest tributaries that drain the liver and empty into the inferior vena cava at the level of the diaphragm |  | 
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        | Term 
 | Definition 
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        | Term 
 | Definition 
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        | Term 
 
        | inferior mesenteric artery (IMA) – |  | Definition 
 
        | arises from the anterior aortic wall at the level of the third or fourth lumbar vertebra to supply the left transverse colon, descending colon, sigmoid colon, and rectum |  | 
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        | Term 
 
        | inferior mesenteric vein (IMV) – |  | Definition 
 
        | drains the left third of the colon and upper colon and joins the splenic vein |  | 
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        | Term 
 
        | inferior vena cava (IVC) – |  | Definition 
 
        | largest venous abdominal vessel that conveys blood from the body below the diaphragm to the right atrium of the heart |  | 
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        | Term 
 
        | left gastric artery (LGA) – |  | Definition 
 
        | arises from the celiac axis to supply the stomach and lower third of the esophagus |  | 
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        | Term 
 
        | left hepatic artery (LHA) – |  | Definition 
 
        | small branch supplying the caudate and left lobes of the liver |  | 
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        | Term 
 
        | left renal artery (LRA) – |  | Definition 
 
        | arises from the posterolateral wall of the aorta directly into the hilus of the kidney |  | 
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        | Term 
 | Definition 
 
        | leaves the renal hilum and travels anterior to the aorta and posterior to the superior mesenteric artery to enter the lateral wall of the inferior vena cava |  | 
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        | Term 
 | Definition 
 
        | hereditary disorder of connective tissue, bones, muscles, ligaments, and skeletal structures |  | 
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        | Term 
 | Definition 
 
        | vessels that have a high diastolic component and supply organs that need constant perfusion (i.e., internal carotid artery, hepatic artery, and renal artery) |  | 
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        | Term 
 | Definition 
 
        | formed by the union of the superior mesenteric vein and the splenic vein near the porta hepatis of the liver |  | 
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        | Term 
 
        | portal venous hypertension – |  | Definition 
 
        | caused by increased resistance to venous flow through the liver; sonographic findings include dilation of the portal and splenic and mesenteric veins, reversal of portal venous blood flow, and the development of collateral vessels |  | 
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        | Term 
 | Definition 
 
        | pulsatile hematoma that results from leakage of blood into soft tissues abutting the punctured artery with fibrous encapsulation and failure of the vessel wall to heal |  | 
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        | Term 
 | Definition 
 
        | vessels that have little or reversed flow in diastole and that supply organs that do not need a constant blood supply (e.g., external carotid artery, brachial arteries) |  | 
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        | Term 
 | Definition 
 
        | peak systole minus peak diastole divided by peak systole (S  D/S = RI); an RI of 0.7 or less indicates good perfusion; an RI of 0.7 or higher indicates decreased perfusion |  | 
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        | Term 
 
        | right gastric artery (RGA) – |  | Definition 
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        | Term 
 
        | right hepatic artery (RHA) – |  | Definition 
 
        | supplies the gallbladder via the cystic artery |  | 
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        | Term 
 
        | right renal artery (RRA) – |  | Definition 
 
        | arises from the posterolateral wall of the aorta and travels posterior to the inferior vena cava to supply the kidney |  | 
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        | Term 
 | Definition 
 
        | leaves the renal hilum to enter the lateral wall of the inferior vena cava |  | 
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        | Term 
 | Definition 
 
        | localized dilation of the vessel |  | 
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        | Term 
 | Definition 
 
        | change in spectral width that increases with flow disturbance |  | 
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        | Term 
 | Definition 
 
        | one of the three vessels that arise from the celiac axis to supply the spleen, pancreas, stomach, and greater omentum |  | 
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        | Term 
 | Definition 
 
        | drains the spleen; travels horizontally across the abdomen (posterior to the pancreas) to join the superior mesenteric vein to form the portal vein |  | 
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        | Term 
 
        | superior mesenteric artery (SMA) – |  | Definition 
 
        | arises inferior to the celiac axis to supply the proximal half of the colon and the small intestine |  | 
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        | Term 
 
        | superior mesenteric vein (SMV) – |  | Definition 
 
        | drains the proximal half of the colon and small intestine; travels vertically (anterior to the inferior vena cava) to join the splenic vein to form the portal veins |  | 
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        | Term 
 | Definition 
 
        | transjugular intrahepatic portosystemic shunt |  | 
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        | Term 
 | Definition 
 
        | permanent dilation of an artery that forms when tensile strength of the arterial wall decreases |  | 
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        | Term 
 | Definition 
 
        | outer layer of the vascular system; contains the vasa vasorum |  | 
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        | Term 
 | Definition 
 
        | inner layer of the vascular system |  | 
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        | Term 
 | Definition 
 
        | middle layer of the vascular system; veins have thinner tunica media than arteries |  | 
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        | Term 
 | Definition 
 
        | tiny arteries and veins that supply the walls of blood vessels |  | 
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        | Term 
 | Definition 
 
        | collapsible vascular structures that carry blood back to the heart |  | 
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