Applied Sono Ch 9

Dissecting aneurysm

Tear in the intima or media of the abdominal aorta

Explain how to differentiate the IVC from the aorta.

The IVC travels in a horizontal course with its proximal position curving slightly anterior as it pierces the diaphragm to empty into the right atrial cavity. The aorta on the other hand, follows the curvature of the spine, with its distal portion lying more posterior, before bifurcating into the iliac vessels.

Common iliac arteries

The abdominal aorta bifurcates at the level of the umbilicus into these, which supply blood to the lower extremities

Gastroduodenal artery

Branch of the common hepatic artery that supplies the stomach and duodenum

The _____ trunk is the first anterior branch of the aorta, arising 1 to 2 cm inferior to the diaphragm.

Celiac

Fusiform aneurysms

Circumferential enlargement of a vessel with tapering at both ends

Veins

Collapsible vascular structures that carry blood back to the heart

Arteriovenous fistula

Communication between an artery and a vein

Anastomosis

Communication between two blood vessels without any intervening capillary network

The ________ originate in the liver and drain into the IVC at the level of the diaphragm.

Hepatic veins

Marfan syndrome

Hereditary disorder of connective tissue, bones, muscles, ligaments, and skeletal structures

How can the sonographer determine that the IVC is dilated?

If the IVC measures greater than 2.0 cm (enlarged) and does not show collapse with expiration.

Spectral broadening (pert. to Doppler)

Increased turbulence is seen within the spectral tracing that indicates flow disturbance

Tunica intima

Inner layer of the vascular system

The large aneurysm may rupture into the peritoneal cavity or retroperitoneum, causing ________ and a drop in ______.

Intense back pain, hematocrit

Aorta

Largest arterial structure in the body; arises from the left ventricle to supply blood to the head, upper and lower extremities, and abdominopelvic cavity

IVC

Largest venous abdominal vessel that conveys blood from the body below the diaphragm to the right atrium of the heart

Right renal vein

Leaves the renal hilum to enter the lateral wall of the IVC

Left renal vein

Leaves the renal hilum, travels anterior to the aorta and posterior to the SMA to enter the lateral wall of the IVC

The ______ flows from the kidney posterior to the superior mesenteric artery and anterior to the aorta to enter the lateral wall of the IVC.

Left renal vein

The root of the aorta arises from the _________ outflow tract in the heart.

Left ventricular

Saccular aneurysms

Localized dilation of the vessel

Tunica media

Middle layer of the vascular system; veins have thinner tunica media than arteries

Capillaries

Minute vessels that connect the arterial and venous systems

Portal venous hypertension

Most commonly results from intrinsic liver disease; however, also results from obstruction of the portal vein, hepatic veins, IVC, or prolonged congestive heart failure; may cause flow reversal to the liver, thrombosis of the portal system, or cavernous transformation of the portal vein

Tunica adventitia

Outer layer of the vascular system, contains the vasa vasorum

The ________ supplies the gallbladder via the cystic artery and the liver.

Right hepatic artery

The ______ courses from the aorta posterior to the IVC and anterior to the vertebral column in a posterior and slightly caudal direction to enter the hilum of the kidney.

Right renal artery

List the 5 sections into which the aorta is divided.

Root of the aorta, descending aorta, abdominal aorta, bifurcation of the aorta into iliac arteries, ascending aorta

The _____ is the second anterior branch, arising approx. 2 cm from the celiac trunk.

SMA

Left hepatic artery

Small branch supplying the caudate and left lobes of the liver

Portal veins become ______ as they progress into the liver from the porta hepatis.

Smaller

Doppler sample volume

Sonographer selects the exact site to record Doppler signals and sets the sample volume (gate) at this site

The ______ artery takes a somewhat tortuous course horizontally to the left as it forms the superior border of the pancreas.

Splenic

The __________ passes anterior to the third part of the duodenum and posterior to the neck of the pancreas, where it joins the splenic vein to form the main portal vein.

Superior mesenteric vein

Right hepatic artery

Supplies the gallbladder via the cystic artery

Right gastric artery

Supplies the stomach

Thrombus usually occurs along the _______ or _______ wall.

Anterior, anteriolateral

The diameter of the abdominal aorta measures approx. ____ cm, tapering to _____ cm after it proceeds inferiorly to the bifurcation into the iliac arteries.

2-3, 1.0-1.5

Describe the effect of gain settings when performing an abdominal aortic ultrasound.

A low to medium gain should be used to demonstrate the walls of the aorta without "noisy" artifactual internal echoes.

Inferior mesenteric artery

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

Splenic artery

Arises from the celiac axis to supply the spleen, pancreas, stomach, and greater omentum

Left gastric artery

Arises from the celiac axis to supply the stomach and lower third of the esophagus

Common hepatic artery

Arises from the celiac trunk to supply the liver

Right renal artery

Arises from the posterolateral wall of the aorta directly into the hilus of the kidney

Left renal artery

Arises from the posterolateral wall of the aorta, travels posterior to the IVC to supply the kidney

Superior mesenteric artery

Arises inferior to the celiac axis to supply the proximal half of the colon and the small intestine

The most common causes of aneurysms are ______ and ______.

Arteriosclerosis, atherosclerosis

Describe the complications of IVC thrombosis.

Complete thrombosis of the IVC is life-threatening. Patients present w/ leg edema, low back pain, pelvic pain, gastrointestinal complaints, and renal and liver abnormalities.

Atherosclerosis

Condition in which the aortic wall becomes irregular from plaque formation

Arteriosclerosis

Disease of the arterial vessels marked by thickening, hardening, and loss of elasticity in the arterial walls

Describe how Doppler is used to distinguish the presence or absence of flow in a vessel from nonvascular structures.

Doppler ultrasound is used to differentiate vessels from nonvascular structures. For example, you could use Doppler to distinguish the CBD from the hepatic artery by looking for absence of flow in the CBD.

Inferior mesenteric vein

Drains the left third of the colon and upper colon and joins the splenic vein

Superior mesenteric vein

Drains the proximal half of the colon and small intestine, travels vertically to join the splenic vein to form the portal veins

Splenic vein

Drains the spleen; travels horizontally across abdomen to join the superior mesenteric vein to form the portal vein

Hepatofugal (pert. to Doppler)

Flow away from the liver

Hepatopetal (pert. to Doppler)

Flow toward the liver

Portal vein

Formed by the union of the superior mesenteric vein and splenic vein near the porta hepatis of the liver

The _______ courses along the upper border of the head of the pancreas, behind the posterior layer of the peritoneal bursa, to the upper margin of the superior part of the duodenum, which forms the lower boundary of the epiploic foramen.

Gastroduodenal artery

Doppler only records accurate velocity patterns when the beam is _____ to the flow.

Parallel

Resistive index (pert. to Doppler)

Peak systole minus peak diastole divided by peak systole

Cavernous transformation of the portal vein

Periportal collateral channels in patients with chronic portal vein obstruction

True aneurysm

Permanent dilation of an artery that forms when tensile strength of the arterial wall decreases

Aneurysm

Permanent localized dilation of an artery, with an increase of 1.5 times its normal diameter

Pseudoaneurysm

Pulsatile hematoma that results from leakage of blood into soft tissue abutting the punctured artery with fibrous encapsulation and failure of the vessel wall to heal

The aorta continues to flow in the ______ cavity anterior and slightly _____ of the vertebral column.

Retroperitoneal, left

Hepatic veins

Three large veins that drain the liver and empty into the IVC at the level of the diaphragm

Budd-Chiari syndrome

Thrombosis of the hepatic vein

Vasa vasorum

Tiny arteries and veins that supply the walls of blood vessels

TIPS

Transjugular intrahepatic portosystemic shunt

Arteries

Vascular structures that carry blood away from the heart

Nonresistive (pert. to Doppler)

Vessels that have high diastolic component and supply organs that need constant perfusion

Resistive (pert. to Doppler)

Vessels that have little or reversed flow in diastole and supply organs that do not need a constant blood supply

Cystic medial necrosis

Weakening of the arterial wall

The normal measurement for an adult abdominal aorta is less than 3 cm, measuring from _______ to ______ walls.

outer to outer