Digestive system Diagnostic imaging department of xuzhou medical college of xuzhou medical college

liver masses

Characterization of liver masses Liver masses malignant benign Hepatocellular carcinoma Cyst Haemangioma FNH （focal nodular hyperplasia） Hepatic adenoma Liver masses malignant benign

Hepatic cyst precontrast contrast

Hepatocellular carcinoma 1. causes liver cirrhosis hepatitis B and C infection

Hepatocellular carcinoma 2. blood supply come mainly from the hepatic artery portal vein invasion is frequently present whereas hepatic vein occurs more rarely

Hepatocellular carcinoma 3. appearances of CT precontrast CT hypo-or isodense a tumor capsule most HCC appear homogeneous, some HCC appear in heterogeneous intrahepatic biliary duct dilatation

Hepatocellular carcinoma 3. appearances of CT Dynamic contrast enhanced CT arterial phase : homogeneous or heterogeneous enhancement hyperattenuating relative to normal parenchyma portal vein phase: enhancement discreased hypoattenuating relative to normal parenchyma wash-in and wash-out

precontrastArterial phase Portal venous phase HCC

precontrast Arterial phase Portal venous phase tumor vessel

Hepatocellular carcinoma

4. appearances of MRI precontrast MRI T1WI: iso-or hypointense tumor capsule : hypointense T2WI: hyperintense DWI: hyperintense

Hepatocellular carcinoma T 1 WI T 2 WI

Hepatocellular carcinoma 4. appearances of MRI Dynamic contrast enhanced MRI similar to the appearances of dynamic contrast enhanced CT arterial phase : obviously enhancement portal vein phase: enhancement discreased wash-in and wash-out

Hepatocellular carcinoma

Hepatic cavernous haemangioma (CH) a very common benign liver tumor usually small (2cm diameter) and solitary, but 10% cases being multiple CH is composed of blood filled large or tortuous vascular cavities divided by thin, often incomplete, fibrous septa and lined by a single layer of flat endothelium

Hepatic cavernous haemangioma (CH) angiography has been used as the gold standard in the past now several noninvasive imaging methods are available such as US, CT, MRI

Hepatic cavernous haemangioma (CH) angiography

Hepatic cavernous haemangioma (CH) appearances of CT precontrast CT hypo-or isoattenuating homogeneous rounded mass usually smaller than 3cm diameter

Hepatic cavernous haemangioma (CH) appearances of CT dynamic contrast enhanced CT arterial phase :peripheral nodular enhancement pattern portal vein phase: a progressive “ fill- in ” of the lesion from the periphery towards the centre

Hepatic cavernous haemangioma (CH) precontrast arterial phase Portal venous phase

precontrast arterial phase Portal venous phaseequilibrium phase Hepatic cavernous haemangioma (CH)

4. appearances of MRI precontrast MRI T1WI: low signal intensity T2WI: high signal intensity “ light bulb ”

4. appearances of MRI Dynamic contrast enhanced MRI similar to the appearances of dynamic contrast enhanced CT arterial phase :peripheral nodular enhancement portal vein phase: a progressive “ fill- in ” from the periphery towards the centre

bile ducts

gallblader Pancreatic duct the ampulla of Vater Common hepatic duct Common bile duct Right hepatic duct left hepatic duct Normal bile ducts

Imaging investigation of jaundice 1. x-ray ERCP endoscopic retrograde cholangiopancreatography used for suspected distal biliary obstruction PTC percutaneous transhepatic cholangiography assess high biliary obstruction at the level of the porta

Imaging investigation of jaundice 2. ultrasound the initial investigation of choice to identify dilated bile ducts and confirm the presence of mechanical biliary obstruction

Imaging investigation of jaundice 3. computed tomography (CT) identifying dilated bile ducts and confirm the presence of mechanical biliary obstruction suggesting the site and cause of bile duct obstruction

Imaging investigation of jaundice 4. magnetic resonance imaging (MRI) identifying dilated bile ducts and confirm the presence of mechanical biliary obstruction suggesting the site and cause of bile duct obstruction MRCP magnetic resonance cholangiography may replace diagnostic ERCP

T2WIT1WI

Gallstones 1. gallstones are classified in three groups pure cholesterol stones: containing more than 90% cholesterol （胆固醇） mixed cholesterol stones: composed of more than 50% cholesterol pigmented ( 色素性 ) stones: composed mainly of calcium salt

Gallstones 2. x-ray only pigmented stones are visible on the AXR ERCP can present most of gallstones, but it is not used for the detection of gallstones because of the widespread availiability of ultrasound

Stones of the gallbladder

ERCP

Gallstones 3. CT pigmented stones are easily depicted on CT cholesterol stones usually have an attenuation value that is lower than bile and are visible on CT

cholesterol stones

pigmented stones

Mixed cholesterol stones

Stones of CBD

Stones of intrahepatic duct

Gallstones 4. MRI MRI and MRCP are able to visualize gallstones reliably ； presenting low signal intensity in T2WI

Stones of gallbladder

Stones of gallbladder and CBD