Liver Flashcards
What are causes of cystic lesions?
Cyst Abscess Hematoma Cystic met Biloma Echinococcus
Rare: Aneurysm Arterioportal fistula Portal-hepatic vein fistula Hemorrhagic adenoma Biliary cystadenoma (carcinoma)
What are typical appearances of a hemangioma?
Homogenous
Hyperechoic
Usually
What is the ddx for hyperechoic masses?
Liver mets
Focal fatty infiltration
Hemangioma
What are contrast enhanced ultrasound findings of hemangioma?
Peripheral puddling of contrast
What are classic US findings for focal nodular hyperplasia?
Isoechoic or near to liver parenchyma
Central Stellate scar better seen on MR or CT
On Doppler can see a spoke-wheel pattern of internal vascularity.
Why do hepatic adenoma a need to be removed? And what is a risk factor for developing?
Risk of bleeding
Oral contraceptive use
What is the most common appearance of metastasis?
Target appearance - echogenic or isoechoic centre with a hypoechoic halo.
What is the ddx for liver target lesions?
Common:
Mets
HCC
Uncommon: Lymphoma FNH Fungal microabscess Adenoma
Ddx for large calcifications? (4)
Metastasis
Fibeolamellar hepatocellular carcinoma
Old hematoma
Old abscess
Ddx for small liver calcifications? (4)
Granulomas
Pneumocystis
Biliary stones
Hepatic arteries
Causes of diffuse hepatic inhomogeneity? (3 common, 3 uncommon)
Common:
Cirrhosis
Metastasis
Fatty infiltration
Uncommon:
HCC
Hepatic fibrosis
Lymphoma
What is the starry sky sign?
Increased echogenicity of portal triads due to hepatitis
Uncommon findings as there is usually no sonographic evidence of hepatitis. Can also be seen without hepatitis.
What are causes of fatty infiltration of the liver?
Obesity Alcohol Cholesterol lowering drugs Chemotherapy Corticosteroids Diabetes Malnutrition TPN Toxins - carbon tetrachloride
What are findings of fatty infiltration?
Diffuse uniform increase in echogenicity
What are typical areas of spared liver parenchyma in fatty infiltration?
Front of right portal vein
Portal bifurcation
Around the gall bladder
What are typical locations of focal fatty infiltration?
Adjacent to falciform ligament
Anterior to portal vein bifurcation
What is a typical waveform of the portal vein described?
Minimal pulsatility
Flow 20-30cm/sec
Antegrade/hepatopetal
How is the normal hepatic vein waveform described?
Retrograde during atrial contraction
Then phase of rapid right atrial filling
Slows then again speeds up when the tricuspid valve opens
What are US findings of portal hypertension?
Ascites Splenomegaly Portal vein enlargement Portosystemic collaterals Enlarged hepatic arteries Hepatofugal/reversed portal flow
What is the classification of portal hypertension?
Intrahepatic:
Post sinusoidal
Presinusoidal
Extrahepatic:
Pre hepatic
Posthepatic
Hyperdynamic
What are causes of intrahepatic portal hypertension? Post/pre sinusoidal
Post sinusoidal:
Cirrhosis
Veno-occlusive disease
Pre sinusoidal:
Hepatic fibrosis
Schistosomiasis
Lymphoma
Sarcoidosis
What are extra hepatic causes of portal hypertension? Pre and post hepatic
Pre hepatic:
Portal vein thrombosis
Portal vein compression
Posthepatic:
Hepatic vein thrombosis
IVC obstruction
Constrictive pericarditis
What are hyper dynamic causes of portal hypertension?
Arterioportal fistula:
Post-Traumatic
Congenital
Atherosclerotic
What are US characteristics of cysts?
Anechoic lumen
Increased through transmission
Well defined back wall
