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.
683 results found
Article
Alagille syndrome
Alagille syndrome (also known as arteriohepatic dysplasia) is a congenital genetic multisystem disorder.
Clinical presentation
Infants typically present with symptoms relating to the liver where it is one of the most common causes of hereditary cholestasis.
Genetics
Alagille syndrome is inhe...
Article
Hepatic arterial resistive index
The resistive index (RI) is the most common Doppler parameter used for hepatic arterial evaluation. The usual range in normal, as well as post-transplant individuals, is between 0.55 and 0.8.
It is measured by:
Resistive index (RI) = (peak systolic velocity - end-diastolic velocity)/peak systo...
Article
Mucocele (general)
A mucocele simply refers to accumulation and expansion of a structure by mucus 1. It occurs in a variety of locations which are discussed separately:
paranasal sinus mucocele
lacrimal mucocele 3
mucocele of the mastoid (rare) 4
mucocele of the oral cavity e.g. ranula, mucous retention cysts...
Article
Saber sign (pneumobilia)
The saber sign refers to a pattern of gas distribution seen in supine abdominal radiographs of patients with pneumobilia. A sword-shaped lucency is apparent in the right paraspinal region of the upper abdomen representing arching gas extending from the common bile duct into the left hepatic duc...
Article
Bile sump syndrome
Bile sump syndrome refers to a complication following a side-to-side choledochoduodenostomy.
Epidemiology
This complication occurs in ~1% of patients following a side-to-side choledochoduodenostomy.
Clinical presentation
Recurrent abdominal pain, cholangitis, pancreatitis, or biliary obstr...
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 cholecystitis 11
postprandial physiological state (pseudothickening)
gallbladder ...
Article
Multiple biliary hamartomas
Multiple biliary hamartomas (MBHs) are a rare cause of multiple benign hepatic lesions. The condition is also known as von Meyenburg complexes, multiple bile duct hamartomas or biliary microhamartomas. Multiple biliary hamartomas are asymptomatic and usually found incidentally, when it is import...
Article
Transient hepatic attenuation differences
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...
Article
Seurat spleen
Seurat spleen is an angiographic appearance seen following blunt trauma to the spleen. Multiple small punctate regions of intraparenchymal contrast extravasation lead to a spotted appearance.
Pathology
Several mechanisms are thought to to attribute to this appearance which include sinusoidal s...
Article
Whole-body CT (protocol)
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.
The majority of the evidence regarding whole-body CT is, understandably, retrospective. There is some e...
Article
Bacillary angiomatosis
Bacillary angiomatosis is an infective complication in those with the acquired immunodeficiency syndrome (AIDS) 3. Amongst other widespread multi-organ manifestations, the infection causes skin lesions which can be similar to those of Kaposi sarcoma.
Pathology
Characterized by a non-neoplastic...
Article
Pancreatic lipomatosis
Pancreatic lipomatosis refers to fat accumulation in the pancreatic parenchyma. This finding is most often associated with obesity and aging. It tends to be the most common pathological condition involving the pancreas. The condition may occasionally simulate a mass-like lesion particularly when...
Article
Hepatoblastoma (staging)
As expected there are a number of different staging systems for hepatoblastoma.
Staging
PRETEXT grouping system of pediatric liver tumors
not specific to hepatoblastoma; used in all pediatric liver tumors
Intergroup staging system
specific for hepatoblastoma (see below)
Intergroup staging ...
Article
Hepatoblastoma histological classification
Although hepatoblastomas can be histologically classified into a variety of subtypes, it is important to remember that with the possible exception of small cell undifferentiated subtype, prognosis is independent of histology when adjusted for stage gender and age 1.
major categories
epithelial...
Article
Epidermoid cyst
Epidermoid cysts are non-neoplastic 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
te...
Article
Santorinicele
A santorinicele refers to a cystic dilatation of the end of the dorsal pancreatic duct (duct of Santorini) 1,2 and is believed to be analogous to a dilatation of the most distal common bile duct, which is commonly known as a choledochocele 3.
It usually occurs in association with pancreas divis...
Article
Hepatoblastoma
Hepatoblastoma is the most common primary malignant liver tumor in children under four years of age who usually present with painless abdominal mass and raised AFP. It is a tumor of embryonic origin.
Epidemiology
Most cases are seen during the first 18 months of life and diagnosis in adulthood...
Article
Serous cystadenoma of the pancreas
Serous cystadenoma of the pancreas, also referred as microcystic adenoma, is an uncommon type of benign cystic pancreatic neoplasm.
Epidemiology
There is a recognized strong female predilection (M:F ~ 1:4) and usually presents in middle age to elderly patients (>60 years of age).
Associatio...
Article
COACH syndrome
The acronym COACH describes a syndrome associated with:
C: cerebellar vermis defect (Joubert syndrome)
O: oligophrenia
A: ataxia
C: coloboma
H: hepatic fibrosis
Epidemiology
COACH syndrome is considered extremely rare.
Associations
The association with infantile polycystic kidney diseas...
Article
Fitz-Hugh-Curtis syndrome
Fitz-Hugh-Curtis syndrome (FHCS), or perihepatitis, is the inflammation of the liver capsule and overlying peritoneum associated with adhesion formation, without the involvement of the hepatic parenchyma. It is a chronic complication of pelvic inflammatory disease (PID).
Epidemiology
The preva...
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
Autosplenectomy
Autosplenectomy denotes spontaneous infarction of the spleen with resulting hyposplenism.
Epidemiology
Autosplenectomy is most frequently encountered in patients with homozygous sickle cell disease, although it has also been reported in pneumococcal septicemia 1, and systemic lupus erythematos...
Article
Pseudocalculus sign (common bile duct)
The pseudocalculus sign is a term coined to describe a mimic of a distally impacted common bile duct (CBD) stone on ERCP, MRCP and the various forms of cholangiography, including T-tube, CT, intraoperative, and percutaneous 1.
It results from the forceful contraction of the choledochal sphincte...
Article
Target sign (choledocholithiasis)
The target sign of choledocholithiasis is a finding seen on contrast-enhanced CT and comprises:
central density within the bile duct: stone
surrounding low density: bile or mucosa
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 up to 20% of patients undergoing cholecystectomy for gallstone-related complaints 2.
Clinical prese...
Article
Transjugular intrahepatic portosystemic shunt
Transjugular intrahepatic portosystemic shunt (TIPS or TIPSS) 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...
Article
Hepatopetal
Hepatopetal denotes flow of blood towards the liver, which is the normal direction of blood flow through the portal vein. The term is typically used when discussing the portal vein or recanalized vein of the ligamentum teres in patients with suspected portal hypertension.
It is the opposite of ...
Article
Hypertrophy of the caudate lobe
Hypertrophy of the caudate lobe is seen in a number of conditions, including:
cirrhosis: most common
Budd-Chiari syndrome
primary sclerosing cholangitis (end stage)
congenital hepatic fibrosis
cavernous transformation of the portal vein
Radiographic features
The caudate-right lobe ratio m...
Article
Cavernous transformation of the portal vein
Cavernous transformation of the portal vein 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 thrombosis.
P...
Article
Hepatic peliosis
Hepatic peliosis is a rare benign vascular condition characterized by dilatation of sinusoidal blood-filled spaces within the liver. There may be involvement of other organs, most commonly the spleen and bone marrow. It can be seen in a variety of settings and is important as appearances may mim...
Article
Hepatic attenuation on CT
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.
Pathology
Several int...
Article
Mirizzi syndrome
Mirizzi syndrome refers to an uncommon phenomenon that results in extrinsic compression of an extrahepatic biliary duct from one or more calculi within the cystic duct or gallbladder. It is a functional hepatic syndrome but can often present with biliary duct dilatation and can mimic other hepat...
Article
Pearl necklace sign
The pearl necklace sign occurs in adenomyomatosis of the gallbladder, on both oral cholecystograms and MRCP. It represents the contrast/fluid-filled intramural mucosal diverticula (Rokitansky-Aschoff sinuses); lined up, these are reminiscent of pearls on a necklace. It is synonymous with the CT ...
Article
Glycogen storage disease
Glycogen storage disease (GSD) refers to a number of syndromes which are characterized by a defect in synthesis, metabolism or storage of glycogen.
Pathology
There are many types of GSD:
type I: von Gierke disease
type II: Pompe disease
type III: Cori or Forbes disease
type IV: Andersen di...
Article
Gallbladder polyp
Gallbladder polyps are commonly occurring elevated lesions on the mucosal surface of the gallbladder. The vast majority are benign. They are best characterized on ultrasound as a non-shadowing endophytic growth into the gallbladder lumen.
Epidemiology
Gallbladder polyps are relatively frequen...
Article
Primary hepatic lymphoma
Primary hepatic lymphoma (PHL) is very rare, with approximately 100 described cases. If it is being considered as a diagnosis, distant lymphadenopathy, splenomegaly, bone marrow disease, and leukemia should not be present for at least 6 months after the liver tumor has been detected (see: second...
Article
Hepatic hemangioma
Hepatic hemangiomas or hepatic venous malformations are the most common benign 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 hemangiomas from hepatic m...
Article
Kaposi sarcoma
Kaposi sarcoma (KS) is a low-to-intermediate grade mesenchymal tumor that involves the lymphovascular system. The tumor can involve the pulmonary, gastrointestinal, cutaneous and musculoskeletal systems. Although it is often thought of as an AIDS-related condition, it may also be seen in other p...
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
Polyarteritis nodosa
Polyarteritis nodosa is a systemic inflammatory necrotizing vasculitis that involves small to medium-sized arteries (larger than arterioles).
Epidemiology
Polyarteritis nodosa is more common in males and typically presents around the 5th to 7th decades. 20-30% of patients are hepatitis B anti...
Article
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. tumor thrombus), and it is a critical ...
Article
Rokitansky-Aschoff sinuses
Rokitansky-Aschoff sinuses are diverticula of the gallbladder wall which may be microscopic or macroscopic. Histologically, they are outpouchings of gallbladder mucosa that sit within the gallbladder muscle layer.
Related pathology
They are not themselves considered abnormal but may be associa...
Article
Post-transplant lymphoproliferative disorder
Post-transplant lymphoproliferative disorder (PTLD), also referred as post-transplant lymphoproliferation disorder, represents a variety of conditions ranging from lymphoid hyperplasia to malignancy, included in the WHO classification of haematolymphoid tumors under "lymphoid proliferations and ...
Article
Giant hepatic hemangioma
Giant hepatic hemangiomas, also known as giant hepatic venous malformations, are relatively uncommon non-neoplastic vascular lesions of the liver, which can be strikingly large and mimic tumors.
Terminology
It is important to note that according to newer nomenclature, these lesions are known ...
Article
Primary sclerosing cholangitis
Primary sclerosing cholangitis (PSC) is an uncommon inflammatory condition that affects the biliary tree resulting in multiple strictures, liver damage, and eventually cirrhosis.
The diagnosis can be made when there are classical imaging features in the correct clinical context, and secondary c...
Article
Splenosis
Splenosis is one type of ectopic splenic tissue (the other being accessory spleen). It is an acquired condition and is defined as autoimplantation of one or more focal deposits of splenic tissue in various compartments of the body.
Pathology
Etiology
Abdominal splenosis is seen after abdomina...
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
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.
Epidemiology
Demographics will match those of the primary tumor, but in general, will be in elderly ...
Article
Puestow procedure
The Puestow procedure or lateral pancreaticojejunostomy is a lateral side-to-side pancreaticojejunostomy that is used for the treatment of chronic pancreatitis.
The pancreas is essentially filleted along its long axis from the uncinate process to the tail and connected to a Roux en-Y loop of je...
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
Pseudocyst
A pseudocyst is an abnormal fluid-filled cavity which is not lined by epithelium. It is this fact that distinguishes it pathologically from a cyst, which is lined by epithelium.
Examples of pseudocysts include:
adrenal pseudocyst
auricular pseudocyst
intraspinal epidural gas pseudocysts
me...
Article
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...
Article
Ultrasound appearances of hepatic metastases
Ultrasound appearance of hepatic metastases can have bewildering variation, and the presence of hepatic steatosis can affect the sonographic appearance of liver lesions.
Radiographic features
Ultrasound
Patterns do exist between ultrasound appearance of the hepatic metastases and the likely p...
Article
Hepatic metastases
Hepatic metastases are 18-40 times more common than primary liver tumors 6. Ultrasound, CT, and MRI are helpful in detecting hepatic metastases and evaluation across multiple post-contrast CT series, or MRI pulse sequences are necessary.
Epidemiology
The demographics of patients with liver me...
Article
Bile duct stricture
Bile duct strictures are problematic in terms of management and distinction between benign and malignant.
Pathology
Etiology
There are numerous causes of biliary duct strictures, including 1,2:
malignant
cholangiocarcinoma
involvement by pancreatic head adenocarcinoma
involvement by ampu...
Article
Rigler triad (gallstone ileus)
Rigler triad consists of three findings seen in gallstone ileus:
pneumobilia
small bowel obstruction
ectopic calcified gallstone, usually in the right iliac fossa
History and etymology
It is named after Leo George Rigler, American radiologist (1896-1979) 1.
Practical points
Rigler triad s...
Article
Bismuth-Corlette classification
The Bismuth-Corlette classification is a classification system for perihilar cholangiocarcinomas, which is based on the extent of ductal infiltration.
Classification
type I
limited to the common hepatic duct, below the level of the confluence of the right and left hepatic ducts
type II
in...
Article
Liver tumors
Liver tumors, like tumors of any organ, can be classified as primary or secondary.
Metastases
Liver metastases are by far the most common hepatic malignancy, with many of the most common primaries readily seeding to the liver. This is especially the case with gastrointestinal tract tumors, due...
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
Focal fatty sparing of the liver
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.
Epidem...
Article
Multiple focal nodular hyperplasia syndrome
Multiple focal nodular hyperplasia occurs in approximately 20-25% of patients with focal nodular hyperplasia (FNH). It is defined by The International Working Party as consisting of two or more FNHs in combination with 1:
liver hemangioma or
vascular malformations (most frequent types: hepatic...
Article
Paracaval lipoma
A paracaval lipoma (also known as juxtacaval fat collection or pseudolipoma of the inferior vena cava) refers to an apparent protrusion of paracaval fat into the inferior vena cava (IVC) and is commonly visible on CT; some believe it to be a normal anatomic variant 5.
Epidemiology
Paracaval l...
Article
Liver protocol (MRI)
Examination of the liver with MRI requires numerous sequences and imaging at multiple times after the administration of contrast.
Note: This article is intended to outline some general principles of protocol design. The specifics will vary depending on MRI hardware and software, radiologist's...
Article
Focal nodular hyperplasia
Focal nodular hyperplasia (FNH) is a regenerative mass lesion of the liver and the second most common benign liver lesion (the most common is a hemangioma). Many focal nodular hyperplasias have characteristic radiographic features on multimodality imaging, but some lesions may be atypical in app...
Article
Pancreatic cancer (staging)
Staging of pancreatic cancer (i.e. ductal adenocarcinoma) is traditionally performed according to the American Joint Committee on Cancer (AJCC) / Union for International Cancer Control (IUCC) TNM system.
In the 2017 new edition (8th edition) AJCC published various major changes including exocr...
Article
Abscess
Abscesses are focal confined collections of suppurative inflammatory material and can be thought of as having three components 1:
a central core consisting of necrotic inflammatory cells and local tissue
peripheral halo of viable neutrophils
surrounded by a 'capsule' with dilated blood...
Article
Caput medusae sign - developmental venous anomalies
The caput medusae sign refers to developmental venous anomalies of the brain, where a number of veins converge centrally into a single draining vein.
The sign is seen on both CT and MRI when contrast medium is administered. Angiographically the caput medusae appearance is seen only in the veno...
Article
Increased splenic density
Increased splenic density can be due to a number of processes. The density may be due to calcification (most common) or other compounds (iron, Thorotrast), and can be seen (often incidentally) on abdominal radiographs and CT. On CT the usual splenic attenuation is 35-55 HU or ~10 HU 6 lower than...
Article
Abdominal surface anatomy
Abdominal surface anatomy can be described when viewed from in front of the abdomen in 2 ways:
divided into 9 regions by two vertical and two horizontal imaginary planes
divided into 4 quadrants by single vertical and horizontal imaginary planes
These regions and quadrants are of clinical imp...
Article
Hepatomegaly
Hepatomegaly refers to an increase in size or enlargement of the liver.
Pathology
Etiology
Hepatomegaly can result from a vast range of pathology including, but not limited to, the following:
malignancy/cellular infiltrate
multiple metastases
lymphoma(s)
leukemia(s)
hepatocellular carci...
Article
Splenomegaly
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.
Terminology
Massive splenomegaly is variably defined, including when the spleen is 5 standar...
Article
Recurrent pyogenic cholangiohepatitis
Recurrent pyogenic cholangiohepatitis, previously known as oriental cholangiohepatitis, is a condition most commonly found in patients residing in or immigrated from Southeast Asia and is characterized by intra and extrahepatic bile duct strictures and dilatation with an intraductal pigmented st...
Article
Melioidosis
Melioidosis is an infectious disease caused by the bacterium Burkholderia pseudomallei (previously known as Pseudomonas pseudomallei) and is a multisystem disorder which may affect the lungs, brain, visceral organs, or musculoskeletal system.
Epidemiology
Melioidosis is a disease of the monsoo...
Article
Portal vein
The portal vein (PV) (sometimes referred to as the main or hepatic portal vein) is the main vessel in the portal venous system and drains blood from the gastrointestinal tract and spleen to the liver.
Terminology
A portal venous system connects two capillary beds, meaning one organ / organ sys...
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
Liver
The liver is the largest abdominal organ. It 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 re...
Article
Pancreas
The pancreas (plural: pancreata) is a mostly 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 enzymes.
Gross anat...
Article
Omentum
An omentum is a double layer of peritoneum that attaches the stomach to another viscus:
the greater omentum hangs from the greater curvature of the stomach like an apron
the lesser omentum attaches the lesser curvature of the stomach to the liver superiorly
Gross anatomy
Greater omentum
The...
Article
Carcinogens
Carcinogens are substances known to cause cancer. They include:
Brain
vinyl chloride
Nasopharynx / nasal cavity
nickel
wood dust
chromium
Thyroid
ionizing radiation
Skin
arsenic
coal tars
polyaromatic hydrocarbons (PAH)
Lungs
arsenic
asbestos
chloromethyl ethers
chromium
coke-o...
Article
Variant hepatic arterial anatomy
Variation in hepatic arterial anatomy is seen in 40-45% of people. Classic branching of the common hepatic artery from the celiac artery, and the proper hepatic artery into right and left hepatic arteries to supply the entire liver, is seen in 55-60% of the population.
Terminology
An accessor...
Article
Wilson disease
Wilson disease, also known as hepatolenticular degeneration, is a rare autosomal recessive disorder of copper metabolism affecting multiple systems.
Epidemiology
It affects 1 in 30,000-40,000 individuals 12. 1 in 90 individuals are a heterozygous carrier 18.
Clinical presentation
The clinic...
Article
Biliary atresia
Biliary atresia is a congenital biliary disorder that is characterized by an absence or severe deficiency of the extrahepatic biliary tree. It is one of the most common causes of neonatal cholestasis, often causing cirrhosis immediately and leading to death and accounts for over half of children...
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 intermediate in size, commonly arising as a terminal branch of the celiac artery, which courses to the right.
Course
It courses posterior to the parietal peritone...
Article
Celiac artery
The celiac artery, also known as the celiac axis or celiac trunk, is a major splanchnic 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 anat...
Article
Hepatic hydatid infection
Hepatic hydatid disease is a parasitic zoonosis caused by the Echinococcus tapeworm. In the liver, two agents are recognized as causing disease in humans:
Echinococcus granulosus
Echinococcus multilocularis
For a general discussion, and links to other system-specific manifestations, ...
Article
Couinaud classification of hepatic segments
The Couinaud classification (French eponym: 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 o...
Article
Water-lily sign (hydatid cyst)
The water-lily sign, also known as the camalote 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...
Article
Strawberry gallbladder
Strawberry gallbladder refers to the surface appearance (not shape) of the mucosa of the gallbladder due to multiple small collections of triglycerides and cholesterol esters within the lamina propria of the gallbladder wall (gallbladder wall cholesterolosis).
Strawberry gallbladder represents...
Article
Splenic cyst
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%)...
Article
Situs inversus
Situs inversus, (rare plural: sitūs inversi) short form of the Latin “situs inversus viscerum”, is a term used to describe the inverted position of chest and abdominal organs.
Terminology
The condition is called situs inversus totalis when there is a total transposition of abdominal and thorac...
Article
Scleroderma
Scleroderma, also known as systemic sclerosis, is an autoimmune connective tissue disorder characterized by multisystem fibrosis and soft tissue calcification. As such, it affects many separate organ systems, which are discussed separately:
musculoskeletal manifestations of scleroderma
pulmona...
Article
Hepatic abscess
Hepatic abscesses, like abscesses elsewhere, are localized 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 affe...
Article
Portal hypertensive gastroenterocolopathy
Portal hypertensive gastroenterocolopathy is a finding in portal hypertension, whereby chronic portal venous congestion leads to dilatation and ectasia of the submucosal vessels of the stomach (portal hypertensive gastropathy), small bowel (portal hypertensive enteropathy) and/or large bowel (po...