Charcot triad is the finding of pyrexia, right upper quadrant pain and jaundice, and is a traditional clinical sign of acute cholangitis.
A meta-analysis of 4288 patients in 16 studies found that the sensitivity of Charcot triad for acute cholangitis was poor (36.3%) with a much better specific...
Chemotherapy induced cholangitis is caused when intra-arterial chemotherapy is introduced to treat liver metastases. This causes strictures of the common hepatic duct and main ducts, but spares distal and proximal (i.e. common bile duct and intrahepatic ducts).
The Child-Pugh score is a scoring system to measure the severity of chronic liver disease inclusive of cirrhosis. The intention is to provide a system with which clinicians can objectively communicate about liver function.
The score is composed from several categories:
total bilirubin, μmol/l ...
Cholangiocarcinoma is a malignant tumor arising from cholangiocytes in the biliary tree. It tends to have a poor prognosis and high morbidity. It is the second most common primary hepatic tumor, with intrahepatic cholangiocarcinomas (ICCs) accounting for 10-20% of primary liver tumors.
Cholangiocarcinoma staging is dependent on whether the tumor is primarily intrahepatic (ICC), hilar/perihilar (Klatskin), or extrahepatic.
Tumor resection is currently the most optimal treatment and the ability of the tumor to infiltrate longitudinally and radially along the biliary tree necess...
Cholangiohepatoma, also referred to as mixed hepatocellular cholangiocarcinoma (HCC-CC), refers to synchronous cholangiocarcinoma and hepatocellular carcinoma (HCC) in the same tumor. It is a rare and aggressive primary hepatic tumor combination. The origin of cholangiohepatoma is closely linked...
Cholangitis is a relatively broad descriptive term referring to inflammation of the bile ducts.
It has many forms and can arise from a number of situations:
primary sclerosing cholangitis
chemotherapy induced cholangitis
eosinophilic cholangitis 5
Cholecystectomies are one of the most common surgical procedures performed. Evidence of a cholecystectomy is often seen on imaging procedures with surgical clips in the gallbladder fossa and radiologists should be aware of possible complications.
Cholecystitis refers to any form of inflammation involving the gallbladder and has many forms including:
acute acalculous cholecystitis
acute calculous cholecystitis
Choledochal cysts represent congenital cystic dilatations of the biliary tree. Diagnosis relies on the exclusion of other conditions (e.g. tumor, gallstone, inflammation) as a cause of biliary duct dilatation.
Choledochal cysts are rare, with an incidence of 1:100,000-150,000. Alt...
Choledochoceles refer to a specific type of choledochal cyst (type III under the Todani classification system). In this type, there is dilatation of the intramural portion of the distal common bile duct within the duodenal wall. Its precise etiology is not clear 3. Patients are usually adolescen...
Choledocholithiasis denotes the presence of gallstones within the bile ducts (including the common hepatic duct/common bile duct).
Choledocholithiasis is relatively common, seen in 6-12% of patients who undergo cholecystectomy 2.
Stones within the bile duct...
Cholescintigraphy is the use of radiotracers to assess the anatomy and function of the biliary system (and the liver indirectly). Currently, this is most commonly performed with Tc-99m-IDA analogs, and "h"epatic "IDA" imaging gave rise to the more common term "HIDA scan."
After intravenous inje...
Chronic cholecystitis refers to prolonged inflammatory condition that affects the gallbladder. It is almost always seen in the setting of cholelithiasis (95%), caused by intermittent obstruction of the cystic duct or infundibulum or dysmotility.
Patients may have a histor...
Chronic pancreatitis represents the end result of a continuous, prolonged, inflammatory and fibrosing process that affects the pancreas. This results in irreversible morphologic changes and permanent endocrine and exocrine pancreatic dysfunction.
The most common cause of chronic p...
Ciliated hepatic foregut cysts are a very rare type of hepatic cyst, with nonspecific radiological features. Less than a hundred of cases have been reported yet 1. They are usually benign, but rare cases of malignant degeneration (in squamous cell carcinoma) have also been reported 1-4.
Cirrhosis (rare plural: cirrhoses) is the common endpoint of a wide variety of chronic liver disease processes which cause hepatocellular necrosis. Cirrhosis can be diagnosed with ultrasound, CT, and MRI, and these imaging modalities can also be used to evaluate for possible complications of cir...
Clonorchiasis is a trematodiasis caused by chronic infestation by Clonorchis sinensis and can lead to recurrent pyogenic cholangitis, biliary strictures and cholangiocarcinoma.
Infection with Clonorchis sinensis occurs in endemic areas, mainly east China. Over 85 million people a...
The cluster sign is a finding on MRI and CT that is associated with pyogenic hepatic abscesses and can help differentiate pyogenic abscesses from other types of liver lesions.
The cluster sign is best seen on MRI T2-weighted and postcontrast T1-weighted sequences. Small n...
Coarsened hepatic echotexture is a sonographic descriptor where there uniform smooth hepatic echotexture of the liver is lost. This can occur due to number of reasons which include:
conditions that cause hepatic fibrosis 1
various types of hepatitis 3
Celiac artery, also known as the celiac axis or celiac trunk, is a major visceral artery in the abdominal cavity supplying the foregut. It arises from the abdominal aorta and commonly gives rise to three branches: left gastric artery, splenic artery, and common hepatic artery.
The celiacomesenteric trunk represents an uncommon vascular anatomical variant where both the celiac trunk and the superior mesenteric artery have a common origin from the abdominal aorta as a single trunk. Its frequency has been reported to occur in about 1.5% of the population 1,2.
The common bile duct (CBD), which is sometimes simply known as the bile duct, is formed by the union of the cystic duct and common hepatic duct (CHD).
On ultrasound imaging, it is not always possible to confidently see where the cystic duct enters the common hepatic duct to form t...
The common hepatic artery (CHA) is one of the 3 branches of the celiac artery.
Origin and course
The CHA is a terminal branch of the celiac arter. It passes over the top of the pancreas, and downwards to the right in the lesser sac towards the first part of duodenum. It gives of...
Confluent hepatic fibrosis is a possible result of chronic injury to the liver, most commonly from cirrhosis or hepatic vascular injury.
Confluent hepatic fibrosis is a cause of wedge-shaped or concave-marginated abnormalities in the cirrhotic liver: It occurs more freque...
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...
Contrast-enhanced ultrasound (CEUS) involves the administration of intravenous contrast agents consisting of microbubbles/nanobubbles of gas.
First-generation ultrasound contrast agents contained microbubbles of air that were dissolved in blood when exposed to acoustic pressure in the ultrasoun...
Copper (chemical symbol Cu) is one of the trace elements. It has an important biological role as a redox agent and as a cofactor in cuproproteins, facilitating many vital metabolic reactions.
Copper is a transition metal with the atomic number 29 and an atomic weight...
Copper toxicity, also known as copper poisoning or copperiedus, is the pathological result of excess elemental copper in the body. It may be acute, resulting in acute copper toxicosis, or a more chronic form, typified by Wilson disease.
Acute copper toxicosis
The cottage loaf sign occurs as a result of a right-sided diaphragmatic rupture with partial herniation of the liver through the diaphragmatic defect. The herniated component is separated by a waist at the diaphragm from the larger intra-abdominal component. This shape is reminiscent of a cottag...
The Couinaud classification (pronounced kwee-NO) is currently the most widely used system to describe functional liver anatomy. It is the preferred anatomy classification system as it divides the liver into eight independent functional units (termed segments) rather than relying on the tradition...
Pauli et al published a "handy" way to remember the Couinaud classification of hepatic segments 1.
Make a fist with your right hand. The fingers should be wrapped around the flexed thumb and the fist should face you. The segments are represented by the following:
segment I: (caudate): the thum...
Courvoisier sign or Courvoisier-Terrier sign states that in a patient with painless jaundice and an enlarged gallbladder (or right upper quadrant mass), the cause is unlikely to be gallstones and therefore presumes the cause to be an obstructing pancreatic or biliary neoplasm until proven otherw...
CT cholangiography is a technique of imaging the biliary tree with the usage of hepatobiliary excreted contrast. It is useful in delineating biliary anatomy, identifying a bile leak or looking for retained gallstones within the biliary system.
Second-line test (after ultrasound) wh...
CT polytrauma/multitrauma, also called trauma CT, whole body CT (WBCT) or panscan, is an increasingly used investigation in patients with multiple injuries sustained after significant trauma.
Clinical assessment and mechanism of injury may underestimate injury severity by 30% 8. There is some e...
The CT severity index (CTSI) is based on findings from a CT scan with intravenous contrast to assess the severity of acute pancreatitis. The severity of computed tomography findings have been found to correlate well with clinical indices of severity.
The CTSI sums two scores:
A cyst is an abnormal fluid-filled structure which is lined by epithelium; with one exception: lung cysts may contain gas or fluid. By contradistinction, a pseudocyst lacks an epithelial lining and instead has a vascular and fibrotic capsule.
Cysts are extremely common and found in most organs....
The cystic artery represents the main blood supply to the gallbladder. It most commonly arises from the right hepatic artery within Calots triangle 1.
The cystic artery typically passes posterior to the cystic duct to reach the neck of the gallbladder. At this point, it gives off...
Cystic fibrosis (CF) is an autosomal recessive genetic disease that affects the exocrine function of the lungs, liver, pancreas, and small bowel resulting in progressive disability and multisystem failure. This article is a general discussion of the disease. Each organ system will be discussed s...
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 liver carry a broad differential diagnosis. These include:
simple hepatic cyst
adult polycystic liver disease
ciliated hepatic foregut duplication cyst 6
infectious: inflammatory conditions
pyogenic hepatic ...
The differential for cystic lesions of the pancreas includes:
intraductal papillary mucinous neoplasm (IPMN)
serous cystadenoma uncommonly uni/macrolocular
simple pancreatic cyst
pancreatic cysts occur in association with
von Hippel Lindau syndrome
The cystic lymph node of Lund (also known as the Calot or Mascagni node) is the sentinel node for the gallbladder, and one of the structures in Calot triangle. It lies in close proximity to the cystic artery and is one of the structures removed during cholecystectomy.
History and etymology
A Denver shunt, or peritoneovenous shunt, is a device used to shunt ascites to the superior vena cava in patients with refractory ascites.
The proximal end is located in the peritoneal cavity and the distal end in the superior vena cava, with a subcutaneous course in the anterior chest wall. It...
Diabetes mellitus (DM) often referred to simply as diabetes, is a group of metabolic conditions characterized by hyperglycemia.
These conditions should not be confused with diabetes insipidus which is clinically distinct and not related to hyperglycemia.
If a patient with diabete...
Diabetic ketoacidosis (DKA) is an acute, life-threatening complication that usually occurs in new-onset and established type 1 diabetic patients due to a state of severe insulin deficiency. This condition is characterized by hyperglycemia, ketoacidosis, and ketonuria.
Diffuse thickening of the gallbladder wall can occur in a number of situations:
gallbladder empyema 7
xanthogranulomatous cholecystitis 11
postprandial physiological state (pseudothickening)
Diffuse hepatic steatosis, also known as fatty liver, is a common imaging finding and can lead to difficulties assessing the liver appearances, especially when associated with focal fatty sparing.
The term 'fatty infiltration of the liver' is often erroneously used to describe live...
Grading of diffuse hepatic steatosis on ultrasound has been used to communicate to the clinician about the extent of fatty changes in the liver.
grade I: diffusely increased hepatic echogenicity but periportal and diaphragmatic echogenicity is still appreciable
grade II: diffusely in...
The dorsal pancreatic artery is a branch of the splenic artery that supplies the pancreas. It arises from the proximal splenic artery and descends a short distance to run along the posterior margin of the pancreas where it divides in to left and right branches.
the right branches pass either an...
Double barrel sign is an imaging appearance of two lumens adjacent to each other.
It can be seen in:
dilated bile duct adjacent to portal vein
double barrel aorta: aortic dissection
double barrel esophagus: esophageal dissection
The double duct sign refers to the presence of simultaneous dilatation of the common bile and pancreatic ducts. Being an anatomical sign it can be seen on all modalities that can visualize the region, including: MRI, CT, ultrasound and endoscopic retrograde cholangiopancreatography (ERCP).
The double target sign is a characteristic imaging feature of liver abscess on contrast enhanced CT scans, in which a central, fluid-filled low attenuation lesion is surrounded by a high attenuation inner rim and a low attenuation outer ring 1,2.
The inner ring (abscess membrane) demonstrates e...
The duct penetrating sign is a radiographic sign which can be useful in differentiating between focal pancreatitis (inflammatory pancreatic mass) from pancreatic carcinoma.
A positive sign is when a mass is penetrated by an unobstructed pancreatic duct; this makes focal pancreatitis the most li...
Dysplastic liver nodules are focal nodular regions (≥1 mm) without definite evidence of malignancy.
They have been found in cirrhotic patients with a prevalence of 14% (size >1.0 cm) to 37% (size >0.5 cm) 2.
Epstein-Barr virus-associated smooth muscle tumors (EBV-SMT) are rare and encountered in immunocompromised individuals.
These tumors are generally exceedingly rare, and only seen with any frequency in the setting of immunosuppression, particularly in HIV/AIDS patients, but also po...
Ectopic intracaval liver is a very rare congenital abnormality of the liver in which a part of the liver, not contiguous with the liver proper, lies within the inferior vena cava (IVC).
Ectopic hepatic lobes elsewhere have been described rarely as congenital abnormalities, but a location withi...
Ectopic pancreatic tissue, also known as heterotopic pancreatic tissue, refers to the presence of pancreatic tissue in the submucosal, muscularis or subserosal layers of the luminal gastrointestinal tract outside the normal confines of the pancreas and lacking any anatomic or vascular connection...
Emphysematous cholecystitis is a rare form of acute cholecystitis where gallbladder wall necrosis causes gas formation in the lumen or wall. It is a surgical emergency, due to the high mortality from gallbladder gangrene and perforation.
Men are affected twice as commonly as women...
Endocrine tumors of the pancreas, also known as pancreatic neuroendocrine tumors (pNET), arise from the pancreatic islet cells and include some distinct tumors that match the cell type of origin.
Pancreatic endocrine tumors have commonly been referred to as "islet cell tumors", re...
Endoscopic retrograde cholangiopancreatography (ERCP) is a diagnostic and interventional procedure technique using both endoscopy and fluoroscopy for examination and intervention of the biliary tree and pancreatic ducts. It is typically performed by doctors with endoscopic qualifications (e.g. g...
Epidermoid cysts are nonneoplastic inclusion cysts derived from ectoderm that are lined solely by squamous epithelium. These are discussed separately by anatomic location:
epidermal inclusion cyst
intracranial epidermoid cyst
splenic epidermoid cyst
spinal epidermoid cyst
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
Extra-hepatic portal vein obstruction is the most common cause of noncirrhotic portal hypertension in children and young adults in developing countries. It may or may not extend into the intrahepatic portal vein.
It usually occurs in children and young adults, presenting ...
Extramedullary hematopoiesis is a response to the failure of erythropoiesis in the bone marrow.
This article aims to a general approach on the condition, for a dedicated discussion for a particularly involved organ, please refer to the specific articles on:
extramedullary hematopoiesis in the...
Extrapulmonary tuberculosis (TB) refers to the haematogenous spread of Mycobacterium tuberculosis.
Extrapulmonary tubercuosis can occur as a primary form of the disease, i.e. direct infection of an extrapulmonary organ without the presence of primary pulmonary tuberculosis or it can ...
The falciform artery, also known as the hepatic falciform artery (FHA) is an uncommon vascular anatomic variant that most commonly arises as the terminal branch of the middle hepatic artery which courses anteriorly through the falciform ligament into and supplying the supraumbilical anterior abd...
The falciform ligament is a broad and thin peritoneal ligament. It is sickle-shaped (Latin: "falciform") and a remnant of the ventral mesentery of the fetus.
It is situated in an anteroposterior plane but lies obliquely so that one surface faces forward and is in contact with the peritoneum beh...
Familial atypical multiple mole melanoma (FAMMM) syndrome is an autosomal dominant genodermatosis characterized by multiple melanocytic nevi (often more than 50) and a family history of melanoma.
It is associated with mutations in the CDKN2A gene and shows reduced penetranc...
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 of which are hepatocellular carcinoma ...
Fetal hepatomegaly (or more simply an enlarged fetal liver) can occur in number of situations. It can occur with or without fetal splenomegaly.
in utero infections
fetal parvovirus B19 infection
fetal cytomegalovirus infection 3
transient abnormal myelopoiesis (TAM) associated...
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 ...
Fibrolamellar hepatocellular carcinoma is a distinct histological variant of hepatocellular carcinoma characterized on microscopy by laminated fibrous layers between the tumor cells. It is important as it has different demographics and risk factors compared to 'standard' hepatocellular carcinoma...
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
A fistula (plural: fistulae) is an abnormal connection between two epithelial surfaces such as between hollow organs, skin or vessels. Conventionally, the name of a specific fistula type is a combination of the two organs
For discussions of specific fistulae please refer to individual articles....
Flash filling hepatic venous malformations, also known as flash filling hepatic hemangiomas, are a type of atypical hepatic venous malformation (hemangioma), which due to its imaging features often raises the concern of a malignant process rather than a benign one.
It is important...
Focal fatty sparing of the liver is the localized absence of increased intracellular hepatic fat, in a liver otherwise fatty in appearance i.e. diffuse hepatic steatosis. Recognition of this finding is important to prevent the erroneous belief that the region of sparing is itself a mass.
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...
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
The focal hepatic hot spot sign can be seen on technetium 99m sulfur colloid scans of the liver and spleen, as well as CT studies.
It occurs as a focal area of increased radiopharmaceutical uptake in the medial segment of the left hepatic lobe (segment IV) due to superior...
Focal hepatic steatosis, also known as focal fatty infiltration, represents small areas of liver steatosis. In many cases the phenomenon is believed to be related to the hemodynamics of a third inflow.
Essentially the same as those that contribute to diffuse hepatic steatosis:
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)
Focal nodular hyperplasia (FNH) is a regenerative mass lesion of the liver and the second most common benign liver lesion (most common is a hemangioma). Many FNHs have characteristic radiographic features on multimodality imaging, but some lesions may be atypical in appearance. FNHs are typicall...
Focused Assessment with Sonography for Trauma (FAST) scan is a point-of-care ultrasound examination performed at the time of presentation of a trauma patient.
It is invariably performed by a clinician, who should be formally trained, and is considered as an 'extension' of the trauma clinical a...
Gadoxetate disodium (also known by the tradenames PrimovistTM and EovistTM) is a hepatospecific paramagnetic gadolinium-based contrast agent, used exclusively in MRI liver imaging. Its chief use is in hepatic lesion characterization, i.e. assessing focal liver lesions identified on other imaging...
The gallbladder is a pear-shaped musculomembranous sac located along the undersurface of the liver. It functions to accumulate and concentrate bile between meals.
The normal adult gallbladder measures from 7-10 cm in length and 3-4 cm in transverse diameter 6. The ga...
Gallbladder adenomas are uncommon gallbladder polyps that, although benign, have a premalignant behavior.
As the distinction of adenomas and intracholecystic papillary-tubular neoplasms (ICPN) is not entirely clear, with important overlap between both entities, some authors have p...
Agenesis of the gallbladder describes the rare congenital absence of the gallbladder.
overall incidence is estimated <0.1% (range 0.04-0.1%)
reported 3:1 female predominance of symptomatic cases
equivalent gender distribution in autopsy cases
Gallbladder carcinoma is a term referring to primary epithelial malignancies arising from the gallbladder, in which the great majority (90%) are adenocarcinomas and the remainder are squamous cell carcinomas. They are more prevalent in elderly women and, in most cases, are only symptomatic when ...
Gallbladder cholecystoses are conditions characterized by the accumulation of cholesterol (and other fats) in the wall of the gallbladder. There are two main forms:
Gallbladder duplication is a rare anatomic anomaly characterized by the presence of an accessory gallbladder. There is no increased risk for malignancy or calculi compared to a single gallbladder.
Prevalence is estimated at 1 in 3000.
Boyden's classification divi...
Gallbladder dysfunction, or functional gallbladder disorder, refers to biliary pain due to motility disturbance of the gallbladder without gallstones, biliary sludge, microlithiasis or microcrystals. The disorder has previous been known by several other names, including gallbladder dyskinesia, g...
Gallbladder empyema (suppurative cholecystitis 1) is an uncommon complication of cholecystitis and refers to a situation where the gallbladder lumen is filled and distended by purulent material (pus).
There is an increased incidence in those with diabetes mellitus 2 and/or advance...