Articles

Articles are a collaborative effort to provide a single canonical page on all topics relevant to the practice of radiology. As such, articles are written and edited by countless contributing members over a period of time. A global group of dedicated editors oversee accuracy, consulting with expert advisers, and constantly reviewing additions.

631 results found
Article

Caroli syndrome

Caroli disease and Caroli syndrome are congenital disorders comprising of multifocal cystic dilatation of segmental intrahepatic bile ducts. Caroli disease is limited to the dilatation of larger intrahepatic bile ducts, whereas Caroli syndrome describes the combination of small bile ducts dilata...
Article

Caudate–right lobe ratio

Caudate-right lobe ratio (C/RL) is used in the assessment of livers, usually in the setting of cirrhosis, in which there is atrophy of the right lobe with hypertrophy of the caudate lobe.  Method for measuring image: axial slice immediately below the bifurcation of the main portal vein line 1...
Article

Cavernous transformation of the portal vein

Cavernous transformation of the portal vein (CTPV) is a sequela of portal vein thrombosis and is the replacement of the normal single channel portal vein with numerous tortuous venous channels. For a discussion of demographics and presentation, please refer to the article on portal vein thrombo...
Article

CEA

Serum CEA (carcinoembryonic antigen) is a cell-adhesive glycoprotein that was discovered in colorectal cancer in 1965, and is hence one of the oldest and most used tumor markers. Its name derives from its normal expression in fetoembryonic liver, gut and pancreas tissue. Normal range of CEA is ...
Article

Ceftriaxone-associated gallbladder pseudolithiasis

Ceftriaxone-associated gallbladder pseudolithiasis is a not uncommon complication of this common antibiotic, where a ceftriaxone-calcium precipitate forms gallbladder sludge. It appears more common in pediatric patients. Epidemiology In one series, 25% of pediatric patients developed gallbladd...
Article

Chain of lakes sign

The chain of lakes sign is a radiological finding describing the appearance of the pancreatic ducts in cases of chronic pancreatitis. Due to repeated inflammation, fibrosis occurs and results in damage and atrophy of the pancreatic tissue as well as dilatation and beading of the main pancreatic ...
Article

Champagne sign (gallbladder)

The champagne sign (also known as the effervescent gallbladder sign) is a pathognomonic sonographic sign of gas in the gallbladder. The sign refers to multiple small echogenic foci which are seen to migrate from a dependent to non-dependent position within the gallbladder as the patient changes...
Article

Charcot triad

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...
Article

Chemotherapy induced cholangitis

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).  Radiographic features similar t...
Article

Child-Pugh score

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 ...
Article

Cholangiocarcinoma

Cholangiocarcinomas (bile duct cancers) are malignant epithelial tumors arising from the biliary tree, excluding the gallbladder or ampulla of Vater. Cholangiocarcinoma is the second most common primary hepatobiliary malignancy after hepatocellular carcinoma (HCC). They tend to have a poor progn...
Article

Cholangiocarcinoma (staging)

Cholangiocarcinoma staging is most commonly classified using the TNM staging systems of the American Joint Committee on Cancer (AJCC)/Union for International Cancer Control (UICC), which starting January 1, 2018 is according to its 8th edition. There are separate systems depending on whether the...
Article

Cholangiohepatoma

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...
Article

Cholangitis

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 infective cholangitis EBV cholangitis ac...
Article

Cholecystectomy

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.  Indications cholelithiasis cholecystitis gal...
Article

Cholecystitis

Cholecystitis refers to any form of inflammation involving the gallbladder and has many forms including: acute cholecystitis acute acalculous cholecystitis acute calculous cholecystitis chronic cholecystitis emphysematous cholecystitis suppurative cholecystitis xanthogranulomatous cholecy...
Article

Choledochal cyst

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. Epidemiology Choledochal cysts are rare, with an incidence of 1:100,000-150,000. Alt...
Article

Choledochocele

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...
Article

Choledocholithiasis

Choledocholithiasis denotes the presence of gallstones within the bile ducts (including the common hepatic duct/common bile duct). Epidemiology Choledocholithiasis is relatively common, seen in 6-12% of patients who undergo cholecystectomy 2. Clinical presentation Stones within the bile duct...
Article

Cholescintigraphy

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...
Article

Chronic cholecystitis

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. Clinical presentation Patients may have a histor...
Article

Chronic pancreatitis

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. Epidemiology The most common cause of chronic ...
Article

Ciliated hepatic foregut cyst

Ciliated hepatic foregut cysts are a very rare type of hepatic cyst, with non-specific radiological features. They are usually benign, but rare cases of malignant degeneration (to squamous cell carcinoma) have also been reported.  Epidemiology They are more often seen in adults, although a few...
Article

Cirrhosis

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...
Article

Cirrhosis (CNS manifestations)

There are several central nervous system complications that can arise in the setting of cirrhosis, which can be classified as those which are general (essentially hepatic encephalopathy) and those that are specific to the cause of cirrhosis. General manifestations The major manifestation is he...
Article

Cirrhosis (musculoskeletal manifestations)

There are several musculoskeletal complications that can arise in the setting of cirrhosis 1: stigmata of portal hypertension, mainly abdominal wall varices hemorrhagic complications due to coagulopathy: spontaneous rectus hematoma postparacentesis abdominal wall bleeding infective complica...
Article

Cirrhosis (pulmonary manifestations)

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 The development of portal hypert...
Article

Clonorchiasis

Clonorchiasis is a trematodiasis caused by chronic infestation by Clonorchis sinensis and can lead to recurrent pyogenic cholangitis, biliary strictures and cholangiocarcinoma.  Epidemiology Infection with Clonorchis sinensis occurs in endemic areas, mainly east China. Over 85 million people a...
Article

Cluster sign

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. Radiographic features The cluster sign is best seen on MRI T2-weighted and postcontrast T1-weighted sequences. Small n...
Article

Coarsened hepatic echotexture

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 cirrhosis hemochromatosis various types of hepatitis 3 particula...
Article

Celiac artery

The 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.  Gross anatom...
Article

Celiacomesenteric trunk

The celiacomesenteric trunk (CMT) 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. Four...
Article

Common bile duct

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).  Terminology On ultrasound imaging, it is not always possible to confidently see where the cystic duct enters the common hepatic duct to form t...
Article

Common hepatic artery

The common hepatic artery (CHA) is one of the 3 branches of the celiac artery. Gross anatomy Origin The common hepatic artery is normally a terminal branch of the celiac artery, the largest branch coursing to the right. Course It passes anterior to the pancreas, and then inferiorly to the r...
Article

Common variable immunodeficiency (hepatic manifestations)

Hepatic manifestations of common variable immunodeficiency are not uncommon and can be primarily related to nodular regenerative hyperplasia. For a general discussion of the underlying condition, please refer to the article on common variable immunodeficiency (CVID).  Epidemiology General liv...
Article

Compression-type hepatic pseudolesions

Compression-type hepatic pseudolesions occur typically when an extrinsic structure, during the patient's deep inspiration breath-hold at the time of CT acquisition, causes transient focal compression of a subcapsular region of the liver and subsequent decreased portal perfusion and minimal chang...
Article

Confluent hepatic fibrosis

Confluent hepatic fibrosis is a possible result of chronic injury to the liver, most commonly from cirrhosis or hepatic vascular injury. Radiographic features Confluent hepatic fibrosis is a cause of wedge-shaped or concave-marginated abnormalities in the cirrhotic liver: it occurs more freque...
Article

Congestive hepatopathy

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...
Article

Contrast-enhanced ultrasound

Contrast-enhanced ultrasound (CEUS) involves the administration of intravenous contrast agents consisting of microbubbles/nanobubbles of gas. Ultrasound contrast agents First generation First-generation ultrasound contrast agents contained microbubbles of air that were dissolved in blood when...
Article

Copper

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. Chemistry Basic chemistry Copper is a transition metal with the atomic number 29 and an atomic weight...
Article

Copper toxicity

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. Clinical presentation Acute copper toxicosis Acute toxi...
Article

Cottage loaf sign (liver)

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...
Article

Couinaud classification of hepatic segments

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...
Article

Couinaud classification of hepatic segments (mnemonic)

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 1: (caudate): the thum...
Article

Courvoisier sign (hepatobiliary)

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...
Article

CT cholangiography

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. Indications Second-line test (after ultrasound) wh...
Article

CT liver volumetry in living donor liver transplantation (approach)

CT liver volumetry in living donor liver transplantation is essential imaging studies in preoperative assessment. Liver volumetry is performed for the donor liver to calculate the graft volume and remnant liver volume. Preoperative measurement of liver volume is important to avoid graft mismatc...
Article

CT liver volumetry (liver transplantation protocol)

CT liver volumetry is an essential imaging study in preoperative assessment for living donor liver transplantation. NB: This article is intended to outline some general principles of protocol design. The specifics will vary depending on CT hardware and software, radiologists' and referrers' pre...
Article

CT polytrauma (technique)

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...
Article

CT severity index in acute pancreatitis

The CT severity index (CTSI) is based on findings from an enhanced CT scan to assess the severity of acute pancreatitis. The severity of acute pancreatitis CT findings has been found to correlate well with clinical indices of severity.  The CT severity index sums two scores: Balthazar score: g...
Article

Cyst

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....
Article

Cystic artery

The cystic artery is the main artery supplying the gallbladder. It most commonly arises from the right hepatic artery within Calot triangle 1. Gross anatomy The cystic artery typically passes posterior to the cystic duct to reach the neck of the gallbladder. At this point, it gives off two-to-...
Article

Cystic fibrosis

Cystic fibrosis (CF), also called mucoviscidosis, is an autosomal recessive genetic disease that affects the exocrine function of the lungs, liver, pancreas, small bowel, sweat glands, and the male genital system 11. resulting in progressive disability and multisystem failure. This article is a ...
Article

Cystic hepatic metastases

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 ...
Article

Cystic lesions of the liver (differential)

Cystic lesions of the liver carry a broad differential diagnosis: simple cysts simple hepatic cyst biliary hamartoma Caroli disease adult polycystic liver disease ciliated hepatic foregut duplication cyst 6 infectious: inflammatory conditions hepatic abscess pyogenic hepatic abscess am...
Article

Cystic lesions of the pancreas (differential)

The differential for cystic lesions of the pancreas includes: unilocular pancreatic pseudocyst intraductal papillary mucinous neoplasm (IPMN) serous cystadenoma uncommonly uni/macrolocular simple pancreatic cyst pancreatic cysts occur in association with  von Hippel Lindau syndrome autos...
Article

Cystic lymph node of Lund

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 The...
Article

Denver shunt

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...
Article

Diabetes mellitus

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. Terminology If a patient with diabete...
Article

Diabetic ketoacidosis

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. Epidemiology Diabetic ket...
Article

Diffuse gallbladder wall thickening (differential)

Diffuse thickening of the gallbladder wall can occur in a number of situations: cholecystitis acute cholecystitis chronic cholecystitis gallbladder empyema 7 xanthogranulomatous cholecystitis 11 acalculous cholecystitis11 postprandial physiological state (pseudothickening) gallbladder o...
Article

Diffuse hepatic steatosis

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. Terminology The term 'fatty infiltration of the liver' is often erroneously used to describe live...
Article

Diffuse hepatic steatosis (grading)

Grading of diffuse hepatic steatosis on ultrasound has been used to communicate to the clinician about the extent of fatty changes in the liver.  Grading grade I: diffusely increased hepatic echogenicity but periportal and diaphragmatic echogenicity is still appreciable grade II: diffusely in...
Article

Distal cholangiocarcinoma (staging)

Distal cholangiocarcinoma staging is defined according to the TNM staging classification of the American Joint Committee on Cancer (AJCC)/Union for International Cancer Control (UICC). As of 2018, the staging criteria are in their 8th edition and reflected below 1. These criteria apply to cancer...
Article

Dorsal pancreatic artery

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...
Article

Double barrel sign (disambiguation)

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
Article

Double duct sign

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...
Article

Double target sign (hepatic abscess)

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...
Article

Duct penetrating sign (pancreas)

Duct penetrating sign is a radiographic sign that 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 likely ...
Article

Dysplastic liver nodules

Dysplastic liver nodules are focal nodular regions (≥1 mm) without definite evidence of malignancy. Epidemiology They have been found in cirrhotic patients with a prevalence of 14% (size >1.0 cm) to 37% (size >0.5 cm) 2. Associations cirrhosis Pathology Dysplasia indicates: nuclear atypia...
Article

EBV associated smooth muscle tumor

Epstein-Barr virus-associated smooth muscle tumors (EBV-SMT) are rare and encountered in immunocompromised individuals. Epidemiology 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...
Article

Ectopic intracaval liver

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...
Article

Ectopic pancreatic tissue

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...
Article

Emphysema (disambiguation)

Emphysema refers to any disease process involving an abnormal accumulation of air/gas in the tissues. When used alone, it is usually taken to mean the lung disease, pulmonary emphysema, which forms part of the spectrum of chronic obstructive pulmonary disease (COPD).  gastric emphysema: include...
Article

Emphysematous cholecystitis

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. Epidemiology Men are affected twice as commonly as women...
Article

Emphysematous hepatitis

Emphysematous hepatitis is a very rare condition characterized by a gas-forming infection of the liver, which in all reported cases has been rapidly fatal. Diabetes mellitus commonly coexists.  Epidemiology Emphysematous hepatitis is extremely rare, with less than 10 reported cases in the lite...
Article

Endocrine tumors of the pancreas

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.  Terminology Pancreatic endocrine tumors have commonly been referred to as "islet cell tumors", re...
Article

Endoscopic retrograde cholangiopancreatography

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...
Article

Epidermoid cyst

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 testicular epiderm...
Article

EUS-guided biliary drainage

Endoscopic ultrasound (EUS)-guided biliary drainage is an alternative to conventional transpapillary and percutaneous biliary drainage in where an extra-anatomic route is created between the biliary tree and the gastrointestinal tract.  Indications failed endoscopic transpapillary biliary drai...
Article

Exclamation mark sign (limy bile)

The exclamation mark sign is a pathognomonic imaging sign of the rare diagnosis of limy bile on plain abdominal radiography. It occurs when there is both limy bile and a gallstone in the common bile duct. The linear vertical radiopaque bile forms the line of the exclamation mark (i.e. !), whilst...
Article

Exophytic hepatic mass

Exophytic hepatic mass or tumor is a lesion which predominantly lies outside the margins of liver but originates from within the liver. Pathology Causes include 1: benign  hepatic hemangioma hepatic adenoma hepatic cyst hepatic angiomyolipoma focal nodular hyperplasia malignant  hepati...
Article

Extrahepatic portal vein obstruction

Extrahepatic portal vein obstruction is the most common cause of non-cirrhotic portal hypertension in children and young adults in developing countries. It may or may not extend into the intrahepatic portal vein. Clinical presentation It usually occurs in children and young adults, presenting ...
Article

Extramedullary hematopoiesis

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...
Article

Extrapulmonary tuberculosis

Extrapulmonary tuberculosis (TB) refers to the hematogenous spread of Mycobacterium tuberculosis. Pathology Extrapulmonary tuberculosis 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 ...
Article

Falciform artery

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...
Article

Falciform ligament

The falciform ligament is a broad and thin peritoneal ligament. It is sickle-shaped 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 behind the right rectus ...
Article

Familial atypical multiple mole melanoma syndrome

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. Pathology Genetics It is associated with mutations in the CDKN2A gene and shows reduced penetranc...
Article

Fat containing liver lesions

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...
Article

Fetal hepatomegaly

Fetal hepatomegaly (or more simply an enlarged fetal liver) can occur in number of situations. It can occur with or without fetal splenomegaly. Pathology Etiology in utero infections: the commonest cause   fetal cytomegalovirus infection (CMV) 3 fetal parvovirus B19 infection in utero syph...
Article

Fetal intrahepatic calcification

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 ...
Article

Fibrolamellar hepatocellular carcinoma

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...
Article

Fibropolycystic liver disease

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 biliary hamartomas autosomal dominant polycystic disease Caroli d...

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.