Fluid-fluid levels in liver lesions are a rare appearance of both benign and malignant conditions.
complicated hepatic cyst 2
hepatic abscess 2
chronic hepatic hematoma 3
biliary cystadenoma 3
hepatic hemangioma (very rare) 2
Periportal lymphadenopathy can be a common observation during imaging of the upper abdomen. What is considered the exact upper limit of normal has been variable 1,3 among different publications but with many authors suggesting a cut-off of around 10 mm in short axis diameter.
Intrahepatic arteriovenous shunts, also referred to as intrahepatic arteriovenous malformations (AVMs) or hepatic arteriosystemic venous shunts, represent a spectrum of abnormal communications between the hepatic arterial system and the hepatic veins.
Please note that arterioportal shunts, whi...
Hepatosplenomegaly is simply the simultaneous presence of a pathologically-enlarged liver (hepatomegaly) and spleen (splenomegaly).
Many infections can produce a mild concurrent enlargement of the liver and spleen. This list is by no means exhaustive.
Gallbladder cancer is relatively uncommon compared to other hepatobiliary malignancies.
gallbladder adenocarcinoma: most common 1
gallbladder squamous cell carcinoma
gallbladder neuroendocrine carcinoma
gallbladder sarcoma: very rare 2
Fibropolycystic liver disease is a collective term for a group of congenital liver and biliary abnormalities resulting from abnormal development of the ductal plates. Disease in this group include:
congenital hepatic fibrosis
autosomal dominant polycystic disease
There are several pulmonary complications that can arise in the setting of cirrhosis:
hepatopulmonary syndrome (HPS): considered the commonest
portopulmonary hypertension (POPH)
hepatic hydrothorax (HH)
intrathoracic portosystemic collateral vessel formation
acute respiratory distress syndr...
Non-neoplastic solid lesions of the pancreas are conditions which may mimic pancreatic neoplasms on imaging. They include:
intrapancreatic accessory spleen
peripancreatic lymph node
Pancreatic atrophy is non-specific and is common in elderly patients, although in younger patients it can be a hallmark of pathology. Most commonly it is associated with aging, obesity and end-stage chronic pancreatitis.
It occurs principally with fatty replacement of the pancreas (pancreatic ...
Thickening of the bile duct wall can stem from a variety of etiologies.
bile duct wall thickening
bile duct walls are typically not visible when normal
possible narrowing of the ducts with obstruction
possible secondary signs of cholangitis, including debri...
Bile duct dilatation refers to the dilatation of intrahepatic or extrahepatic bile ducts.
Variable, depending on the underlying cause, but usually:
right upper quadrant pain
Harmonic imaging is useful when assessing the bilia...
Focal gallbladder wall thickening is an imaging finding that includes both benign and malignant etiologies.
gallbladder carcinoma: look for infiltration into adjacent organs, metastases, lymphadenopathy, bile duct dil...
Cystic hepatic metastases are included in the differential for new cystic liver lesions. The internal cystic component may represent necrosis as the tumor outgrows its hepatic blood supply, or it may represent a mucinous component, similar to the primary tumor.
The liver and lungs are the most ...
Cystic lesions of the liver carry a broad differential diagnosis:
simple hepatic cyst
adult polycystic liver disease
ciliated hepatic foregut duplication cyst 6
infectious: inflammatory conditions
pyogenic hepatic abscess
Pseudocirrhosis is a radiological term used to convey the imaging findings of cirrhosis, but emphasize that it occurs in the setting of hepatic metastases. It is most commonly reported following chemotherapeutic treatment of breast cancer metastases, although has also been reported before treatm...
Exophytic hepatic mass or tumor is a lesion which predominantly lies outside the margins of liver but originates from within the liver.
Causes include 1:
focal nodular hyperplasia
Congestive hepatopathy includes a spectrum of hepatic derangements that can occur in the setting of right-sided heart failure (and its underlying causes). If there is subsequent hepatic fibrosis the term cardiac cirrhosis may be used. The condition can rarely occur as a result of non-cardiac cau...
Hepatic capsular retraction is an uncommon finding that is defined as loss of the normal liver contour due to focal flattening/irregularity or concavity. It is related to several benign and malignant pathologies.
The list of differential diagnoses associated with hepatic...
Pancreatic calcifications can arise from many etiologies.
Punctate intraductal calcifications
alcoholic pancreatitis (20-40%) 2
intraductal, numerous, small, irregular
preponderant cause of diffuse pancreatic intraductal calcification
gallstone pancreatitis (2%) 2
Periampullary tumors are those that arise within 2 cm of the ampulla of Vater in the duodenum.
Tumors that fall under this group include four main types of tumors 1,4 that will be approached in their specific articles:
pancreatic head/uncinate process tumors: includes pancreatic ductal adenoca...
Coarsened hepatic echotexture is a sonographic descriptor used when the uniform smooth hepatic echotexture of the liver is lost. This can occur due to a number of reasons which include:
conditions that cause hepatic fibrosis 1
various types of hepatitis 3
Pancreatitis (plural: pancreatitides) refers to inflammation involving the pancreas.
It has various forms which can be classified in many, many ways according to time of onset, etiological agent or associated pathology.
interstitial edematous pancreatitis
Fat containing liver lesions represent a variety of benign and malignant liver lesions may contain macroscopic and/or intracytoplasmic fat in sufficient quantities enabling characterization on imaging studies. Most fat-containing liver lesions (80%) in patients with cirrhosis are malignant, most...
Medical devices in the abdomen and pelvis are important to be recognized, just like medical devices of the chest. We often ignore these devices, considering them to be incidental and non-pathological, however it is essential to be aware of potential complications.
Fetal intrahepatic calcification can be a relatively common finding. Calcifications in the liver can be single or multiple and in most cases in which isolated hepatic calcific deposits are detected, there is usually no underlying abnormality.
The presence of isolated intrahepatic calcification ...
Periportal hyperechogenicity can result from many causes including:
schistosomiasis of the portal region
recurrent pyogenic cholangitis (oriental)
inflammatory bowel disease: has been described to give "echo-rich" periportal cuffing 2
Periportal hypoechogenicity can result from many causes:
orthotopic liver transplant rejection
malignant lymphatic obstruction
Retained gallstones, also called dropped or slipped gallstones, are common during a laparoscopic cholecystectomy, with a reported incidence of 0.1–20%, and occur when gallstones are inadvertently spilled into the peritoneal cavity.
Many cases of dropped gallstones will be...
Hemobilia refers to the presence of blood in the biliary tree.
The classical clinical triad, only seen in ~50% of cases, consists of:
melena (i.e. upper gastrointestinal bleeding)
iatrogenic: surgical or percutaneous proced...
Focal hypodense hepatic lesions on a non-contrast CT scan can result from a number of pathological entities, including:
biliary hamartoma: von Meyenberg complexes 2
hepatoma/hepatocellular carcinoma (HCC)
Causes of generalized increase in hepatic echogenicity include:
diffuse fatty change
cirrhosis: and/or coarsening
chronic hepatitis 3: and/or coarsening
diffuse infiltration or deposition
glycogen storage disease
Causes of generalized reduction of liver echogenicity on ultrasound include:
diffuse malignant infiltration
generalized increase in liver echogenicity
hepatic attenuation on CT
Bulging duodenal papilla is a conical or cylindrical protuberance at the medial aspect of the descending or horizontal duodenum at the site of the sphincter of Oddi. It is a finding on small bowel follow-though (and endoscopy) and has a relatively long differential. On cross-sectional imaging, ...
Focal gas collection in right upper quadrant on plain radiographs can occur from a number of pathologies. Things to consider are:
enterobiliary fistula: common types include cholecystoduodenal fistula and cholecystocolic fistula. It may occur with:
gallstone ileus (being most common) 3
Diffuse thickening of the gallbladder wall can occur in a number of situations:
gallbladder empyema 7
xanthogranulomatous cholecystitis 11
acalculous cholecystitis 11
postprandial physiological state (pseudothickening)
Transient hepatic attenuation differences (THAD) lesions refer to areas of parenchymal enhancement visible during the hepatic artery phase on helical CT. They are thought to be a physiological phenomenon caused by the dual hepatic blood supply. Occasionally, they may be associated with hepatic t...
Hypertrophy of the caudate lobe is seen in a number of conditions, including:
cirrhosis: most common
primary sclerosing cholangitis (end stage)
congenital hepatic fibrosis
cavernous transformation of the portal vein
The caudate-right lobe ratio m...
Hepatic attenuation on CT, reflected by Hounsfield values, depends on a combination of factors including the presence or absence, as well as the phase, of IV contrast administration.
Allowing for all these factors, the mean unenhanced attenuation value is around 55 HU 4.
Ultrasound appearance of hepatic metastases can have bewildering variation, and the presence of hepatic steatosis can affect the sonographic appearance of liver lesions.
Patterns do exist between ultrasound appearance of the hepatic metastases and the likely p...
Splenomegaly refers to enlargement of the spleen. The upper limit of the normal adult splenic length is traditionally cited at 12 cm, but lengths upwards of 14 cm can be seen in normal, taller males 7.
Massive splenomegaly is variably defined, including when the spleen is 5 standar...
Splenic epithelial cysts, also known as splenic epidermoid cysts or primary splenic cysts, are unilocular fluid lesions with thin and smooth walls and no enhancement. They represent ~20% of cysts found in the spleen, and are usually an innocuous incidental imaging finding.
Note that most (~80%)...
There are numerous primary pancreatic neoplasms, in part due to the mixed endocrine and exocrine components.
Classification based on function
exocrine: ~99% of all primary pancreatic neoplasms
pancreatic ductal adenocarcinoma ~90-95%
intraductal papillary muc...
Hypervascular liver lesions are findings that enhance more or similarly to the background hepatic parenchyma in the late arterial phase, on contrast-enhanced CT or MRI.
hepatocellular carcinoma (HCC)
most common hypervascular primary liver malignancy
The differential for cystic lesions of the pancreas includes:
intraductal papillary mucinous neoplasm (IPMN)
serous cystadenoma uncommonly uni/macrolocular
simple pancreatic cyst
cystic neuroendocrine tumor of the pancreas
diffuse pancreatic cysts