Liver Flashcards
Name LI-RADS major imaging criteria for HCC
Arterial phase hyper-enhancement
PV/delayed venous phase washout
capsular enhancement
threshold growth (new lesion >10mm)
When can you call fatty liver on T2
Compare to spleen. If liver hyperintense then there is fatty infiltration
Name of FNH specific MRI contrast
Primovist
Pathological difference between FNH and hepatic adenoma? (Cell that is absent)
Kupffer cells are absent in hepatic adenoma. Otherwise they both contain normal hepatocytes in an abnormal configuration
Name the top 3 differential diagnoses of a hyperdense liver on C-
Amiodarone therapy Iron deposition (oral intake, blood transfusions, thalassemia/sideroblastic anemia, hemochromatosis) Glycogen storage disease (types 1 and 4)
What is T2 signal of regenerative nodules in cirrhosis?
Hypointense, which allows differentiation from metastases (hyper T2)
Daughter cysts within a larger cyst are pathognomonic of which pathology?
Hydatid cyst (echinococcal infection)
Name the different types of choledochal cysts (Todani)
type I: most common, accounting for 80-90%
Ia: dilatation entire of extrahepatic bile duct
Ib: focal dilatation of extrahepatic bile duct
Ic: dilatation of the common bile duct portion of extrahepatic bile duct
type II: true diverticulum from extrahepatic bile duct
type III: dilatation of extrahepatic bile duct within duodenal wall (choledochocoele)
type IV: next most common
IVa: cysts involving both intra and extrahepatic ducts
IVb: multiple dilatations/cysts of extra hepatic ducts only
type V: multiple dilatations/cysts of intra hepatic ducts only (Caroli disease)
What contrast timing and speed demonstrates hypervascular liver masses best?
Late arterial phase (35 sec, PV opacified)
Injection rate of 5cc/sec allows more contrast to reach liver
Radiologyassistant
How do you differentiate benign hypervascular liver lesions (regen nodules, FNH, adenoma) from HCC on CT?
Delayed phase will demonstrate washout in HCC whereas the other masses will remain isodense to liver parenchyma
Ddx of liver masses with retained contrast on delayed phase (10min)?
Hemangioma - blood pool HCC - fibrous capsule FNH - central scar Cholangiocarcinoma - scar Fibrolamellar carcinoma - scar
How is the scar of FNH different from scar of other tumors on imaging?
On MRI, the scar of an FNH will be hyperT2 because of oedema whereas in other masses it will be hypoT1T2
Ddx of hypervascular liver metastases?
Breast Sarcoma RCC Melanoma Neuroendocrine (carcinoid, islet cell, pheochromocytoma)
Most common liver tumor with a capsule?
HCC
The capsule is fibrous and enhances on delayed views
Other masses with a capsule are adenoma, cystadenoma and cystadenocarcinoma
Central calcifications are seen in what type of liver masses?
Hemangioma
Metastases (especially colon)
Cholangiocarcinoma
Fibrolamellar carcinoma
How do you differentiate benign hypervascular liver lesions (regen nodules, FNH, adenoma) from HCC on CT?
Delayed phase will demonstrate washout in HCC whereas the other masses will remain isodense to liver parenchyma
Ddx of liver masses with retained contrast on delayed phase (10min)?
Hemangioma - blood pool HCC - fibrous capsule FNH - central scar Cholangiocarcinoma - scar Fibrolamellar carcinoma - scar
How is the scar of FNH different from scar of other tumors on imaging?
On MRI, the scar of an FNH will be hyperT2 because of oedema whereas in other masses it will be hypoT1T2
Ddx of hypervascular liver metastases?
Breast Sarcoma RCC Melanoma Neuroendocrine (carcinoid, islet cell, pheochromocytoma)
Most common liver tumor with a capsule?
HCC
The capsule is fibrous and enhances on delayed views
Other masses with a capsule are adenoma, cystadenoma and cystadenocarcinoma
Central calcifications are seen in what type of liver masses?
Hemangioma
Metastases (especially colon)
Cholangiocarcinoma
Fibrolamellar carcinoma
Ddx of fat containing liver tumor? (4)
Adenoma
HCC
Metastatic liposarcoma
Angiomyolipoma
Describe nutmeg liver appearance and Ddx
Due to perfusion abnormality usually as a result of hepatic venous congestion. It is a mottled pattern of enhancement in arterial and early PV phases with decreased enhancement of liver periphery. The liver becomes more uniform on delayed images.
Ddx:
Hepatic veno-occlusive disease
Budd-Chiari syndrome
Congestive hepatopathy - right heart failure, constrictive pericarditis
What is characteristic MR appearance of primary sclerosing cholangitis
Multiple stenoses
Minor dilatations (from periductal fibrosis)
Beaded appearance of bile ducts
Findings of cirrhosis can also be present