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.

493 results found
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Thorotrast

Thorotrast is a radioactive radiographic contrast agent containing thorium dioxide first produced in Germany in 1928 and was in use until the 1950s. It was used primarily for cerebral angiography, and 90% of the estimated 50,000-100,000 patients who received it were studied for this purpose.  T...
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Pancreatic metastases

Pancreatic metastases are uncommon and are only found in a minority (3-12%) of patients with widespread metastatic disease at autopsy . They account for only 2-5% of all pancreatic malignancies. Although essentially any primary may eventually deposit in the panaceas the most common primaries en...
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Hypervascular liver lesions

Hypervascular liver lesions may be caused by primary liver pathology or metastatic disease. Differential diagnosis Primary lesions hepatocellular carcinoma (HCC) most common hypervascular primary liver malignancy early arterial phase enhancement and then rapid wash out rim enhancement of c...
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Periportal halo

Periportal halo or periportal collar sign is a zone of low attenuation seen around the portal veins on contrast-enhanced CT or hypoechogenicity on liver US. Periportal halos may occur around the central portal veins or their peripheral branches and occurs on both sides of the portal triads. Pat...
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Water-lily sign (hydatid cyst)

The water-lily sign is seen in hydatid infections when there is detachment of the endocyst membrane which results in floating membranes within the pericyst that mimic the appearance of a water lily. It is classically described on plain radiographs (mainly chest X-ray) when the collapsed membran...
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Niemann-Pick disease

Niemann-Pick disease (NPD) is actually a collection of a number of distinct autosomal recessive lysosomal storage diseases. They are divided into two groups of two based on the underlying metabolic deficiency: deficiency of acid sphingomyelinase 1,3,4 Niemann-Pick disease type A (NPD-A) sever...
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Niemann-Pick disease type C

Niemann-Pick disease type c (NPD-C or just NPC) is an autosomal recessive lysosomal storage disorder classed under Niemann-Pick disease on account of clinical similarities, namely hepatosplenomegaly and variable involvement of the central nervous system.  Epidemiology NPD-C is inherited as a a...
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Cystic lesions of the liver (differential)

Cystic lesions of liver carry a broad differential diagnosis. These include: simple cysts simple hepatic cyst biliary hamartoma Caroli disease adult polycystic liver disease infectious: inflammatory conditions hepatic abscess pyogenic hepatic abscess amoebic hepatic abscess hepatic hyd...
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Intrabiliary rupture of hepatic hydatid cyst

Intrabiliary rupture of hepatic hydatid cyst is a common complication associated with hepatic hydatid cysts. It is important to appreciate the direct and indirect signs of this condition. Radiographic features The radiological features of intrabiliary rupture of a hepatic hydatid cyst can be c...
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Splenic calcification

Splenic calcifications can occur is various shapes and forms and can occur from a myriad of aetiological factors. The usual calcification observed in radiographs are the multiple, miliary form presenting numerous small rounded densities averaging from three to five millimeters in diameter where...
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Splenic cyst

Splenic epithelial cysts, also referred 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 (~8...
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Jaundice

Jaundice refers to a clinical sign of hyperbilirubinemia (>2.5 mg/dl) which has many causes. It is often a clue to a diagnosis. It can be largely divided into two types: non-obstructive, i.e. pre-hepatic and hepatic causes obstructive, i.e. post-hepatic causes Imaging has a major role in dete...
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Gilbert syndrome

Gilbert syndrome is a hereditary condition which can result in jaundice. Pathology It is results in intermittent unconjugated hyperbilirubinemia in the absence of hepatocellular disease or haemolysis. Uridine diphosphate-glucuronyl transferase activity is reduced resulting in indirect hyperbil...
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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...
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Papillary process of the caudate lobe

The papillary process, or medial process, of the caudate lobe represents a division of the inferior portion of the caudate lobe of the liver 1. When enlarged, either as a variant anatomy or because of cirrhosis, it can mimic a hepatic or pancreatic mass, or be confused with retroperitoneal or p...
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Focal gallbladder wall thickening (differential)

Focal gallbladder wall thickening is an imaging finding that includes both benign and malignant etiologies. cholecystoses cholesterolosis adenomyomatosis masses gallbladder polyps gallbladder carcinoma: look for infiltration into adjacent organs, metastases, lymphadenopathy, bile duct dil...
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Diffuse gallbladder wall thickening (differential)

Diffuse thickening of the gallbladder wall can occur in a number of situations. They include: cholecystitis acute cholecystitis chronic cholecystitis gallbladder empyema 7 xanthogranulomatous cholecystitis acalculous cholecystitis postprandial physiological state (pseudothickening) sec...
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Wilson disease

Wilson disease, also known as hepatolenticular degeneration, is a rare autosomal recessive disorder of copper metabolism affecting multiple systems.  Epidemiology Wilson disease is commonly found in Japan. It affects 1 in 30,000-40,000 individuals 12. Clinical presentation Clinical presentat...
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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...
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Portal venous gas

Portal venous gas is the accumulation of gas in the portal vein and its branches. It needs to be distinguished from pneumobilia, although this is usually not too problematic, when associated findings are taken into account along with the pattern of gas (i.e. peripheral in portal venous gas, cent...
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Hepatomegaly

Hepatomegaly refers to an increase in size or enlargement of the liver.  Pathology Aetiology Hepatomegaly can result from a vast range of pathology including, but not limited to, the following: malignancy/cellular infiltrate multiple metastases lymphoma(s) leukaemia(s) hepatocellular car...
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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 visualise the region, including: MRI, CT, ultrasound and endoscopic retrograde cholangiopancreatography (ERCP).  The...
Article

Sarcoidosis (abdominal manifestations)

Sarcoidosis is a systemic inflammatory disease of unknown origin characterized by the formation of non-caseating granulomas. Virtually any organ system may be involved.  Although the involvement of abdominal viscera is less frequent than pulmonary and mediastinal disease when it occurs, it may m...
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Sonographic Murphy sign

Sonographic Murphy sign is defined as maximal abdominal tenderness from pressure of the ultrasound probe over the visualised gallbladder 1,2. It is a sign of local inflammation around the gallbladder along with right upper quadrant pain, tenderness and/or a mass 2. It is one of the most importa...
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Biliary necrosis

Biliary necrosis refers to the death of the intra-hepatic bile ducts epithelium commonly seen as a complication of hepatic artery thrombosis.  Pathology Different from the liver parenchyma that has dual supply, portal vein and hepatic artery, the intrahepatic biliary ducts are exclusively supp...
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Focal nodular hyperplasia

Focal nodular hyperplasia (FNH) is a regenerative mass lesion of the liver and the second most common benign liver lesion (most common is a haemangioma). Many FNHs have characteristic radiographic features on multimodality imaging, but some lesions may be atypical in appearance. FNHs are typical...
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Giant hepatic venous malformation

Giant hepatic venous malformations (also known as giant hepatic haemangiomas) are relatively uncommon non-neoplastic vascular lesions of the liver, which can be strikingly large and mimic tumours.  Terminology It is important to note that according to newer nomenclature, these lesions are mere...
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Pancreatic duct diameter

The diameter of the (main) pancreatic duct is a commonly assessed parameter in imaging. Gross anatomy The duct diameter is greatest at the head and neck region and is slightly narrower towards the body and tail. Its normal reported value ranges between 1-3.5 mm 5, 8: head: 3.5 mm body: 2.5 m...
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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...
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Extramedullary haematopoiesis

Extramedullary haematopoiesis 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 to a particularly involved organ, please refer to the specific articles on:  extramedullary haematopoiesis in th...
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Hepatic hydrothorax

Hepatic hydrothorax (HH) is an uncommon manifestation of cirrhosis with ascites. It is one of the pulmonary complications of cirrhosis with portal hypertension.  It is characterised by formation of pleural effusions usually greater than 500 mL, in patients with portal hypertension without any o...
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Coeliac artery

Coeliac artery, also known as the coeliac axis or coeliac 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 anatomy...
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Pancreaticopleural fistula

Pancreaticopleural fistulas are a rare complication of acute or chronic pancreatitis whereby enzymatic pancreatic fluid, either from a pancreatic pseudocyst or directly from a disrupted duct, dissects into the pleural cavity. Pancreaticopleural fistulas may also develop in the setting of trauma ...
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Passive hepatic congestion

Passive hepatic congestion, also known as congested liver in cardiac disease, describes the stasis of blood in the hepatic parenchyma, due to impaired hepatic venous drainage, which leads to dilation of central hepatic veins and hepatomegaly.  Passive hepatic congestion is a well-studied result...
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Hepatic haemangioma

Hepatic haemangiomas are benign neoplastic vascular liver lesions. They are frequently diagnosed as an incidental finding on imaging, and most patients are asymptomatic. From a radiologic perspective, it is important to differentiate haemangiomas from hepatic neoplasms. Epidemiology Hepatic ha...
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Liver

The liver is the largest abdominal organ that plays a major role in metabolism and has a number of functions, including glycogen storage, decomposition of red blood cells, plasma protein synthesis, hormone production, and detoxification. It is one of the very few organs that has the ability to r...
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Glisson's capsule

Glisson's capsule is the external fibrous layer that envelops liver lobules.​ Related pathology Right upper quadrant pain can be caused by distension of Glisson's capsule 3. This can be caused by several processes, including a haematoma or a mass. History and etymology It is named after Fran...
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Liver sinusinoids

Liver sinusoids are a type of fenestrated/porous blood vessels which compose the 'capillary bed' of the liver parenchyma. They receive terminal branches of the oxygen-rich hepatic artery (terminal hepatic arterioles) and nutrient-rich portal vein (terminal portal venules). They facilitate vascul...
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Liver lobules

Liver lobules are the basic functional units of the liver. They are classically described ('classic lobules') as hexagonal structures made of six vertically aligned portal canals with a central vein. However, microscopic evaluation of the liver usually shows a lack of classic liver lobule as a w...
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Acute hepatitis

Acute hepatitis occurs when the liver suffers an injury with a resulting inflammatory reaction. The cause of the injury can happen in multiple different ways, and imaging findings are often non-specific. Acute hepatitis is a clinical diagnosis and normal imaging appearance of the liver does not ...
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Hepatic abscess

Hepatic abscesses, like abscesses elsewhere, are localised collections of necrotic inflammatory tissue caused by bacterial, parasitic or fungal agents.  Epidemiology The frequency of individual infective agents as causes of liver abscesses are intimately linked to the demographics of the affec...
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Percutaneous cholecystostomy

Percutaneous cholecystostomy is an image-guided placement of drainage catheter into gallbladder lumen. This minimally invasive procedure can aid stabilisation of a patient to enable a more measured surgical approach with time for therapeutic planning. Indications poor surgical candidate/high r...
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Percutaneous transhepatic biliary drainage

Percutaneous transhepatic biliary drainage is an interventional radiology procedure undertaken for those with biliary obstruction. It is almost exclusively performed in those with malignant obstruction, such as cholangiocarcinoma, ampullary and pancreatic malignancies when retrograde access via...
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Percutaneous transhepatic cholangiography

Percutaneous transhepatic cholangiography (PTC) is a radiographic technique employed in visualisation of the biliary tree and can be used as the first step in a number of percutaneous biliary interventions (e.g. percutaneous transhepatic biliary stent placement) Indications Purely diagnostic p...
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Sickle cell disease

Sickle cell disease (SCD) is a hereditary (autosomal recessive) condition resulting in the formation of abnormal haemoglobin (a haemoglobinopathy), which manifests as multisystem ischaemia and infarction, as well as haemolytic anaemia.  Epidemiology There is no recognised gender predilection. ...
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Selective internal radiation therapy

Selective internal radiation therapy (SIRT), also know as hepatic radioembolisation, is a relatively new and developing modality for treating non-resectable liver tumours. The procedure consists of a transcatheter injection of radioactive particles via hepatic artery.  It generally considered e...
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Transjugular intrahepatic portosystemic shunt

Transjugular intrahepatic portosystemic shunt (TIPS) is a treatment for portal hypertension in which direct communication is formed between a hepatic vein and a branch of the portal vein, thus allowing some proportion of portal flow to bypass the liver. The target portosystemic gradient after TI...
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Liver biopsy (transjugular)

Transjugular liver biopsy (TJLB) is an alternative to a percutaneous liver biopsy in patients with diffuse liver disease, coagulopathy and ascites. It is sometimes done in combination with a transjugular intrahepatic portosystemic shunt (TIPSS) or venography. Indications massive ascites coag...
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Ultrasound guided biopsy

Ultrasound guided biopsy is one form of image guided biopsy, typically performed by a radiologist.  It is the most common form of image guided biopsy, offering convenience and real time dynamic observation with echogenic markers on cannulae allowing for precise placement. It can potentially be ...
Article

Haemochromatosis

Haemochromatosis is an iron overload disorder characterised by a progressive increase in total body iron stores and deposition of iron in some non-reticuloendothelial system (RES) body organs which results in some instances in organ dysfunction. This article focus on the general principles of h...
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Hepatic hydatid infection

Hepatic hydatid disease is a parasitic zoonosis caused by the Echinococcus tapeworm. In the liver, two agents are recognised as causing disease in the human: Echinococcus granulosus Echinococcus multilocularis For a general discussion, and for links to other system specific manifestations, p...
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Portal vein thrombosis

Portal vein thrombosis may be seen in a variety of clinical contexts, and when acute can be a life-threatening condition. It is a major cause of non-cirrhotic presinusoidal portal hypertension. Portal vein thrombus may be either bland and/or malignant (i.e. tumour thrombus), and it is a critical...
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Splenic infarction

Splenic infarction is a result of ischaemia to the spleen, and in many cases requires no treatment. However, identification of the cause of infarction is essential.   Epidemiology Splenic infarcts can occur due to a number of processes, involving either arterial supply, the spleen itself or th...
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Primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is an uncommon idiopathic inflammatory condition, which affects the biliary tree resulting in multiple strictures and eventual cirrhosis. The diagnosis can be made when there are classical imaging features in the correct clinical context, and secondary cause...
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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...
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Pneumobilia

Pneumobilia, also known as aerobilia, is the accumulation of gas in the biliary tree. It is important to distinguish pneumobilia from portal venous gas, the other type of branching hepatic gas. There are many causes of pneumobilia and clinical context is often important to distinguish between th...
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Hepatic lymphoma

Hepatic lymphoma is a term given to any form of hepatic involvement with lymphoma. This can be broadly divided into: secondary hepatic involvement with lymphoma: most common by far, many tend to be non-Hodgkin lymphoma (NHL) 1 primary hepatic lymphoma: extremely rare Pathology Risk factors f...
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Pancreatic neoplasms

There are numerous primary pancreatic neoplasms, in part due to the mixed endocrine and exocrine components. Classification Classification based on function exocrine: ~99% of all primary pancreatic neoplasms pancreatic ductal adenocarcinoma ~90-95% cystic neoplasm intraductal papillary muc...
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Hepatic infarction

Hepatic infarction is an extremely rare situation because of the liver's dual blood supply by the hepatic artery and portal vein. Hepatic infarction can occur when there is both hepatic arterial and portal vein flow compromise but most cases are due to acute portal venous flow compromise 11. Ep...
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Periportal hyperechogenicity

Periportal hyperechogenicity can result from many causes including: pneumobilia cholecystitis schistosomiasis of the portal region recurrent pyogenic cholangitis (oriental) inflammatory bowel disease: has been described to give "echo-rich" periportal cuffing 2​  It may also be observed in ...
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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...
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Limy bile

Limy bile stands for the presence of a viscous substance in the dependent parts of the gallbladder and/or bile ducts, almost entirely composed of calcium carbonate, and therefore highly radiopaque. Terminology The terms limy bile and calcium milk gallbladder can be used interchangeably for inc...
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Bile duct dilatation (differential)

Bile duct dilatation can be due to several aetiologies. Clinical presentation Variable, depending on underlying cause, but usually: right upper quadrant pain jaundice Radiographic features Ultrasound Harmonic imaging is useful when assessing the biliary system, as it improves the clarity ...
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Starry sky appearance (ultrasound)

A starry sky appearance refers to a sonographic appearance of the liver parenchyma in which there are bright echogenic dots throughout a background of decreased liver parenchymal echogenicity. Although usually associated with acute hepatitis, this sign has been found to have poor sensitivity and...
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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...
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Geographic appearance

Geographic appearance is a term used in imaging, and other clinical fields (e.g. histopathology) to describe lesions with a well-circumscribed margins with adjacent tissues.  The term derives from the somewhat similar appearance of the outline of countries on a map or the clear demarcation forme...
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Focal fatty sparing of the liver

Focal fatty sparing of the liver is the localised 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. Epidem...
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Nutmeg liver

A nutmeg liver appearance is due to a perfusion abnormality of the liver usually as result of hepatic venous congestion. When hepatic veins are congested, contrast is prevented from diffusing through the liver in a normal manner. This results in a mottled pattern of contrast enhancement in the a...
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Pancreatic pseudocyst

Pancreatic pseudocysts are common sequelae of acute pancreatitis or chronic pancreatitis, and the most common cystic lesion of the pancreas. They are important both in terms of management and differentiation from other cystic processes or masses in this region. Terminology The following are th...
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Greater pancreatic artery

The greater pancreatic artery, also known as the pancreatica magna artery, is a branch of the splenic artery that supplies the pancreatic tail and body. It arises approximately two thirds the way along the splenic artery and descends a short distance to run to the left along the posterior margi...
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Liver trauma

The liver is one of the most frequently damaged organs in blunt trauma, and liver trauma is associated with a significant mortality rate. Epidemiology In blunt abdominal trauma, the liver is injured ~5% (range 1-10%) of the time 1,3. Clinical presentation Patients can present with right uppe...
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Gallstone pancreatitis

Gallstone pancreatitis refers to pancreatitis caused by gallstones, specifically distal choledocholithiasis. Gallstones is the cause for 35-40% of acute pancreatitis but this number has a wide regional variance.  Epidemiology Gallstone pancreatitis has a higher incidence in women (compared to ...
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Choledocholithiasis

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

The transverse pancreatic artery, also known as the inferior pancreatic artery, is a branch of the splenic artery that supplies the pancreatic tail and body. It arises from the proximal splenic artery and descends a short distance to run to the left along the posterior margin of the pancreas ne...
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Pancreas

The pancreas is a retroperitoneal organ that has both endocrine and exocrine functions: it is involved in the production of hormones (insulin, glucagon and somatostatin), and also involved in digestion by its production and secretion of pancreatic juice. Gross anatomy The pancreas can be divid...
Article

Hepatic artery proper

The hepatic artery proper or the proper hepatic artery arises from the common hepatic artery as it divides into its two terminal branches, the hepatic artery proper and the gastroduodenal artery.  Gross anatomy Course The hepatic artery proper runs to the right anterior to the portal vein and...
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Superior pancreaticoduodenal artery

The superior pancreaticoduodenal artery is a branch of gastroduodenal artery that supplies the duodenum and pancreas. Gross anatomy Superior pancreaticoduodenal artery arises after branching off from gastroduodenal artery. It divides into anterior and posterior divisions which supply the pylor...
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Gastroduodenal artery

The gastroduodenal artery (GDA) is a terminal branch of the common hepatic artery which mainly supplies the pylorus of the stomach, proximal duodenum, and the head of the pancreas. Due to its proximity to the anterior wall of the first part of the duodenum, the gastroduodenal artery is one of th...
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

Infantile hepatic haemangioma

Infantile hepatic haemangiomas (IHH) are a liver lesion composed of large endothelial-lined vascular channels seen in fetuses and neonates. It should not be confused with a hepatic epithelioid haemangioendothelioma, which occurs in older patients. Terminology Those benign tumours were previous...
Article

Splenic hydatid infection

Splenic hydatid infection is a rare form of hydatid disease, and isolated splenic involvement is even less common. For a general discussion, and for links to other system specific manifestations, please refer to the article on hydatid disease.  Epidemiology Splenic hydatid disease has been re...
Article

Hepatic lipoma

Hepatic lipomas are rare, usually asymptomatic, benign lesions of the liver. Pathology They may be composed purely of fat cells, or they may be mixed with adenomatous, angiomatous or myomatous tissue, resulting in lesions such as adenolipoma, angiomyolipoma or myelolipoma 5. Associations tub...
Article

T tube cholangiogram

T-tube cholangiograms are a fluroscopic study performed in the setting of hepatobiliary disease.  This technique has been largely superseded by MRCP and ERCP. Typically a T-shaped tube is left in the common bile duct at the time of surgery (e.g. cholecystectomy) and allows for exploration of th...
Article

Budd-Chiari syndrome

Budd-Chiari syndrome refers to the clinical picture that occurs when there is partial or complete hepatic venous outflow obstruction. It is characterised on imaging by ascites, caudate hypertrophy, peripheral atrophy, and prominent collateral veins.  Epidemiology Budd-Chiari syndrome is rare. ...
Article

Intraductal papillary mucinous neoplasm

Intraductal papillary mucinous neoplasms or tumours (IPMNs or IMPTs) are cystic tumours of the pancreas. Epidemiology These tumours are most frequently identified in older patients (50-60 years of age) 6, and thus are sometimes colloquially referred to as the "grandfather lesion". Main duct ty...
Article

Gallbladder polyp

Gallbladder polyps are elevated lesions on the mucosal surface of the gallbladder. The vast majority are benign, but malignant forms are seen. Gallbladder polyps may be detected by ultrasound, CT, or MRI, but are usually best characterised on ultrasound. Epidemiology Gallbladder polyps are rel...
Article

Caput medusae sign (portal hypertension)

The caput medusae sign is seen in patients with severe portal hypertension. It describes the appearance of distended and engorged paraumbilical veins, which are seen radiating from the umbilicus across the abdomen to join the systemic veins.  History and etymology The appearance is reminiscent...
Article

Acute acalculous cholecystitis

Acute acalculous cholecystitis refers to the development of cholecystitis in a gallbladder either without gallstones or with gallstones where they are not the contributory factor. It is thought to occur most often due to biliary stasis and/or gallbladder ischaemia. Epidemiology Acute acalculou...
Article

HELLP syndrome

HELLP syndrome is a pregnancy-related condition and is an abbreviation for: haemolysis elevated liver enzymes and  low platelets It is considered a severe and life-threatening form of pre-eclampsia although it can occur without co-existing pre-eclampsia.  Epidemiology The estimated inciden...
Article

Hepatic adenoma

Hepatic adenomas, also referred as hepatocellular adenomas, are benign liver tumours generally hormone induced. The tumours are usually solitary, have a predilection for haemorrhage, and must be differentiated from other focal liver lesions. Epidemiology The incidence of hepatic adenomas is un...
Article

Ampullary tumour

The term ampullary tumour generally refers to either benign or malignant neoplasms that arise from the glandular epithelium of the ampulla of Vater, including 1: ampullary adenoma (adenoma of ampulla of Vater) ampullary carcinoma (carcinoma of ampulla of Vater) According to some authors, ampu...
Article

Hypertriglyceridaemia-induced pancreatitis

Hypertriglyceridaemia-induced pancreatitis is an uncommon form of acute pancreatitis caused by high levels of circulating triglycerides in the blood. Epidemiology Hypertriglyceridaemia-induced pancreatitis accounts for around 1-4% of cases of acute pancreatitis and is the third most common cau...
Article

Ascaris-induced pancreatitis

Ascaris-induced pancreatitis is the most common form of parasite-induced pancreatitis. Epidemiology Ascariasis in parts of India is the second most common form of pancreatitis after gallstones 1. It is rare outside of endemic regions however. Clinical presentation The presentation will be si...

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