Class 20: Abdominal Vascular Pathology Flashcards
where is the most common location for a dissecting aneurysm to occur?
thoracic aorta
where is the most common location for a saccular aneurysm to occur?
thoracic aorta
where is the most common location for a fusiform aneurysm to occur?
infrarenal
what are 2 common causes for a dissecting aneurysm?
- idiopathic
- marfan’s syndrome
what is marfan’s syndrome?
a connective tissue disease leading to a weak tunica media
ultrasound appearance of a dissecting aneurysm?
double channel with a vibrant intimal flap
3 most common sites of aneurysms
- infrarenal
- distal aorta
- common iliacs
4 common causes of aneurysms
- atherosclerosis
- congenital disorders
- giant cell arteritis
- infection
what is giant cell arteritis?
inflammatory disease of blood vessels
S&S of AAA?
- abdominal, back, or groin pain
- palpable pulsatile abdominal mass
- 30-60% patients are asymptomatic & discovered incidentally
when is surgical intervention needed for AAA?
- when aneurysm is 5+ cm
- aneurysm is < 5cm but grows >1 cm/year
normal proximal aorta measurement?
2.3 cm
normal mid aorta measurement?
2.0 cm
normal distal aorta measurement?
1.8. cm
normal aorta measurement before bifurcation?
1.5 cm
what is aorta ectasia?
aorta is up to 3.0 cm; genetic, normal; all organs are typically large
when is the aorta considered aneurysmal?
> 3 cm
why does thrombus usually form at the walls of an aneurysm?
velocities at walls are decreased, leading to stagnant blood during diastole
the main portal vein is formed by which 2 veins?
- SMV
- splenic v
the right portal vein divides into which two branches?
anterior & posterior branch
the left portal vein divides into which two branches?
medial & lateral branches
the portal veins course ___-segmentally in the liver
intrasegmetally
the hepatic veins course ____-segmentally in the liver
intersegmentally
the hepatic veins have more echogenic walls than the portal veins. T/F?
false
what is the normal diameter of the main portal vein?
< 13 mm
normal flow of the portal vein with measurement?
low velocity, continuous flow
20-40 cm/s
normal portal vein flow is hepatofugal. T/F?
false – hepatopedal
what is portal hypertension?
increased pressure in portal vein due to increased impedance of flow through liver
3 causes for portal hypertension?
- prehepatic
- intrahepatic
- posthepatic
normal measurement for spleen?
< 13 cm
when evaluating the portal vein, all doppler should have low ___ & ___ ___
PRF/scale & wall filter
what are 2 porto-systemic shunts when there is portal HTN?
- recanalized paraumbilical vein/ligamentum teres
- splenorenal shunt
with a splenorenal shunt, where is the flow going?
from splenic vein to left renal vein
what does TIPS stand for?
transjugular intrahepatic portosystemic shunt
what is TIPS?
a stent is placed in the liver between portal vein & hepatic vein
what is the purpose for TIPS?
decompression of portal venous system
what does the right hepatic vein divide the liver into?
divides the right lobe into anterior & posterior segments
what does the middle hepatic vein divide the liver into?
divides the liver into left & right lobe
what does the left hepatic vein divide the liver into?
divides the left lobe into medial & lateral segments
what is another name for the medial segment of the left lobe of the liver?
quadrate lobe
what is budd-chiari syndrome?
hepatic vein outflow obstruction
with budd-chiari syndrome, there may be no visualization of the ___ ___ ____
right hepatic vein
with budd-chiari, there may be discontinuity between the ___ ___ ___ & ___
main hepatic vein & IVC
with budd-chiari, you may find a ___ flow in the hepatic veins
reversed
with budd-chiari, what findings may arise with the IVC?
no flow
slow flow
bidirectional flow
narrowing
