Liver, Biliary Tree, and Gallbladder Flashcards
What is the current method of choice for most hepatic imaging?
Dynamic bolus contrast-enhanced MDCT
What modality is used as a screening method for patients with abdominal symptoms and suspected diffuse or focal liver disease?
Ultrasound
Modality used in the characterisation of cavernous hemagiomas and focal nodular hyperplasia.
Radionuclide imaging
Maximum enhancement of the liver occurs on what phase? (MDCT protocols)
Portal venous phase - to demonstrate hypovascular lesions as low-attenuating masses on a background of brightly enhanced parenchyma.
Maximum enhancement of the liver parenchyma occurs how many seconds after hepatic arterial enhancement?
60 to 120 seconds
What divides the liver into right and left lobes?
A longitudinal plane through the middle hepatic vein, inferior vena cava, and gallbladder fossa.
Portal venous flow may be altered by what circumstances?
- Portal blockade by tumour or thrombus
- Extrinsic compression caused by ribs or diaphragm stocks slips, or tumors of the liver capsule
- “Third inflow” from systemic veins in the pericholecystic, paramilitary, and epigastric-paraumbilical venous system
Increased hepatic arterial flow me be due to what situations?
- Focal hypervascular lesions
- Inflammation of adjacent organs (cholecystitis and pancreatitis)
- Aberrant hepatic arterial supply
The echogenicity of the liver parenchyma is homogeneous and equal to or slightly greater than what structure?
Kidney
What is the preferred screening method for biliary obstruction?
Ultrasound
What modality or method is used primarily to guide therapy such as stent placement for biliary strictures, stone extraction, or sphincterectomy?
Endoscopic retrograde cholangiography
What method is mainly used to guide therapy when the biliary tree cannot be accessed endoscopically such as when the patients have choledochojejustomy?
Percutaneous transhepatic cholangiography
Bile ducts arise at what structures?
As bile capillaries between hepatocytes and join progressively larger two main trunks are formed draining the right and left lobes of the liver.
The ducts of the left hepatic lobes are located in what position in relation to the right hepatic lobe?
More anterior
Failure to fill the biliary ducts (on contrast study) before gravitational repositioning must not be interpreted as?
As evidence of obstruction