Gallbladder ghost triad is a term used on ultrasound studies when there is a combination of three gallbladder features on biliary atresia:
atretic gallbladder, length less than 19 mm
irregular or lobular contour
lack of smooth/complete echogenic mucosal lining with an indistinct wall
Gallbladder hydrops refers to marked dilatation of the gallbladder due to chronic obstruction of the cystic duct resulting in accumulation of sterile non-pigmented mucin.
Abdominal pain with palpable gallbladder without any signs of infection. In an asymptomatic patient, ...
Gallbladder inflammatory polyps are a benign subtype of gallbladder polyps, representing ~10% of all polyps. They appear as a result of chronic inflammation (chronic cholecystitis).
For further details, please refer to the parental article on gallbladder polyps.
Gallbladder malignancy (or gallbladder cancer) is relatively uncommon. The commonest histopathological type is carcinoma.
gallbladder adenocarcinoma: most common 1
gallbladder squamous cell carcinoma
gallbladder neuroendocrine carcinoma
gallbladder sarcoma: ve...
Gallbladder metastases are rare and usually represent an advanced and end-stage of malignancy. Malignant melanoma and gastric carcinoma account for the most common primary malignancies to see metastases to the gallbladder, in the Western and Asian societies, respectively.
Gallbladder perforations are a serious complication of acute cholecystitis and represent an advanced stage of the disease. They tend to occur in an elderly and/or comorbid demographic and carry higher rates of morbidity and mortality.
Symptoms and clinical signs are varia...
Gallbladder polyps are elevated lesions on the mucosal surface of the gallbladder. The vast majority are benign, but malignant forms are seen.
On imaging, although they may be detected by CT or MRI, they are usually best characterized on ultrasound as a non-shadowing and immobile polypoid ingro...
Gallbladder sludge, also known as biliary sand, biliary sediment, or thick bile, is a mixture of particulate matter and bile, normally seen as a liquid-liquid level in the gallbladder on ultrasound, corresponding to the precipitate of bile solutes.
The term biliary microlithiasis ...
Gallbladder triplication is an extremely rare anomaly. There are three types of gallbladder triplication are described according to the number of cystic duct and their insertion:
Three gallbladders and three cystic ducts which unite to form a common cystic duct before joining the common bile du...
Gallbladder volvulus is a relatively rare condition in which there is a rotation of the gallbladder around the axis of the cystic duct and artery.
Symptoms are non-specific, however right upper quadrant pain and vomiting are similar to biliary colic. Laboratory evaluation...
Gallbladder wall cholesterolosis is a type of cholecystosis, therefore, results from the accumulation of cholesterol esters and triglycerides in the macrophages within the gallbladder wall. It is a benign condition that may occur in two forms:
diffuse: strawberry gallbladder
Thickening of the gallbladder wall is a non specific sign of various conditions. The diagnosis can be made by US, CT, or MRI depending on the clinical scenario.
Gallbladder wall thickening can be caused by inflammatory, benign and malignant etiologies. Pseudothickening caused by the ...
This is a basic article for medical students and other non-radiologists
Gallstone disease represents a group of conditions that are linked to, or caused by, gallstones. These stones are formed from sludge in the gallbladder and may range from millimeters in diameter to several centimeters. 90% ...
Gallstone ileus is an uncommon cause of a mechanical small bowel obstruction. It is a rare complication of chronic cholecystitis 7 and occurs when a gallstone passes through a fistula between the gallbladder and small bowel before becoming impacted at the ileocecal valve.
Gallstone pancreatitis refers to pancreatitis caused by gallstones, specifically distal choledocholithiasis. Gallstones are the cause for 35-40% of acute pancreatitis but this number has a wide regional variance.
Gallstone pancreatitis has a higher incidence in women (compared to...
Gallstones, also called cholelithiasis, are concretions that may occur anywhere within the biliary system, most commonly within the gallbladder.
Gallstones (cholelithiasis) describe stone formation at any point along the biliary tree. Specific names can be given to gallstones depe...
Gangrenous cholecystitis is the most common complication of acute cholecystitis, affecting ~15% (range 2-30%) of patients.
Gangrenous cholecystitis occurs as a result of ischemia with necrosis of the gallbladder wall 4.
Gastric varices are an important portosystemic collateral pathway, occurring in ~20% of patients with portal hypertension. They are considered distinct from esophageal varices in that they have a propensity to hemorrhage at comparatively lower portal pressures 1, and are also associated with hig...
Gastrinomas are the second most common pancreatic endocrine tumor and the most common type in the setting of multiple endocrine neoplasia type I (MEN I).
Most gastrinomas are sporadic, although some are seen in the setting of multiple endocrine neoplasia type I (MEN I). In general...
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...
Causes of generalized increased liver echogenicity include:
diffuse fatty infiltration
cirrhosis: can be coarsened as well
chronic hepatitis 3: can be coarsened as well
diffuse infiltration or deposition
Causes of generalized reduction of liver echogenicity on ultrasound include:
diffuse malignant infiltration
generalized increase in liver echogenicity
hepatic attenuation on CT
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...
Giant hepatic venous malformations (also known as giant hepatic hemangiomas) are relatively uncommon non-neoplastic vascular lesions of the liver, which can be strikingly large and mimic tumors.
It is important to note that according to newer nomenclature, these lesions are merely...
Gilbert syndrome is a hereditary condition which can result in jaundice.
It is results in intermittent unconjugated hyperbilirubinemia in the absence of hepatocellular disease or hemolysis. Uridine diphosphate-glucuronyl transferase activity is reduced resulting in indirect hyperbili...
Glisson's capsule is the external fibrous layer that envelops liver lobules.
Right upper quadrant pain can be caused by distension of Glisson's capsule 3. This can be caused by several processes, including a hematoma or a mass.
History and etymology
It is named after Franc...
Glucagonomas are pancreatic endocrine tumors that secrete glucagon. Most lesions are malignant.
They are very rare with an incidence of ~0.000005% or less than 1 case per 20 million. Equal incidence in middle-aged men and women.
Most patients present with ...
Glycogen storage disease (GSD) refers to a number of syndromes which are characterized by a defect in synthesis, metabolism or storage of glycogen.
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...
Glycogen storage disease type II, also known as Pompe disease or acid maltase deficiency disease, is an inherited lysosomal disorder characterized by abnormal glycogen accumulation within lysosomes. It is a multisystem disorder involving the heart, skeletal muscle and liver. It is caused by a de...
Granulomatous hepatitis refers to an inflammatory liver disease associated with granuloma formation in the liver. These can caseating or non-caseating.
It can be associated with a wide variety of conditions, which most commonly includes
sarcoidosis: hepatic manifestati...
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...
Gullo syndrome, also known as benign pancreatic hyperenzymaemia, is characterized by the abnormal elevation of the serum levels of most or all of the pancreatic enzymes without any evidence of underlying pancreatic pathology. All other laboratory assays and imaging studies are unremarkable.
Abdominal complications of hematopoietic stem cell transplantation can occur early (0-100 days) or late (>100 days) post-transplant.
bacterial infections, e.g. pseudomembranous colitis
fungal infections, often affecting the esophagus or as hepatic/splenic microabscesses
Hemobilia refers to the presence of blood in the biliary tree.
The classical clinical triad, only seen in ~50% of cases, consists of:
melena (i.e. upper gastrointestinal bleeding)
iatrogenic: surgical or percutaneous proced...
Hemochromatosis is an iron overload disorder characterized 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 he...
Hemorrhagic cholecystitis refers to an inflammatory process of the gallbladder, complicated by hemorrhage into the lumen.
The presenting features may mimic non-hemorrhagic acute cholecystitis, with right upper quadrant pain being a dominant feature. If the blood is passe...
Hemorrhagic pancreatitis is characterized by bleeding within or around the pancreas, and is usually considered a late sequela of acute pancreatitis.
Hemorrhage can occur in patients with severe necrotizing pancreatitis or as a result of pancreatic pseudoaneurysm rupture when it const...
HELLP syndrome is a pregnancy-related condition and is an abbreviation for:
elevated liver enzymes and
It is considered a severe and life-threatening form of pre-eclampsia although it can occur without co-existing pre-eclampsia.
The estimated inciden...
Hepascore is a biochemical severity scoring system based on liver function tests in predicting the extent of liver fibrosis/cirrhosis in patients with hepatitis C infection. Hepascore may also be applicable to other liver diseases and is being trialed for fatty liver disease and hepatitis B infe...
Hepatic abscesses, like abscesses elsewhere, are localized collections of necrotic inflammatory tissue caused by bacterial, parasitic or fungal agents.
The frequency of individual infective agents as causes of liver abscesses are intimately linked to the demographics of the affec...
Hepatic adenomas, also referred to as hepatocellular adenomas, are benign, generally hormone-induced, liver tumors. The tumors are usually solitary, have a predilection for hemorrhage, and must be differentiated from other focal liver lesions.
The incidence of hepatic adenomas is ...
Hepatic adenomatosis is the presence of numerous, more than 10 and up to 50, hepatic adenomas. It is a rare disorder, best characterized with MRI.
Patients with hepatic adenomatosis do not necessarily have the classic risk factors associated with the development of hepatic adenoma...
Hepatic adrenal rest tumors (HART), previously been termed primary hypernephroma of the liver or hypernephroid carcinoma of the liver, are very rare liver tumors with histology similar to adrenocortical carcinoma.
It tends to occur in younger patients and there is no recognized g...
Hepatic amyloidosis refers to the extracellular deposition of amyloid in the parenchyma sinusoids or vessel walls. Liver involvement in amyloidosis is uncommon.
It can be primary or secondary and it typically occurs as diffuse infiltration 2.
There is amyloid deposition in liver p...
Hepatic angiomyolipoma (HAML) is an uncommon benign hamartomatous hepatic mass lesion, containing blood vessel (angioid), smooth muscle (myoid) and mature fat (lipoid) components. There is an association with tuberous sclerosis, although this is less strong than for renal AMLs.
Hepatic angiosarcoma is a rare malignancy but is still the third most common primary liver tumor. They have a variable appearance on both CT and MRI reflecting the pleomorphic histological nature. Prognosis is very poor, with survival uncommon beyond one year from diagnosis.
The resistive index (RI) is the commonest 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:
RI = (peak systolic velocity - end diastolic velocity)/peak systolic velocity
The hepatic artery proper, also known as the proper hepatic artery (PHA), is the continuation of the common hepatic artery after it gives off the gastroduodenal artery. Just prior to the porta hepatis it divides into the left and right hepatic arteries.
The hepatic artery...
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.
Hepatic capsular retraction is an uncommon finding related to several benign and malignant pathologies and also intrinsic or extrinsic causes; a list of differential diagnoses is given below:
malignant tumor (primary or metastatic) - especially cholangiocarcinoma but hepatocellular carcinoma is...
The following mnemonics can be used as reminders of the causes of hepatic capsular retraction:
C: cholangiocarcinoma (intrahepatic)
T: treated hepatic metastasis or hepatocellular carcinoma
C: cirrhosis with confluent hepatic fibrosis
H: hemangioma (es...
Primary hepatic carcinoid is an extremely rare type of carcinoid tumor, with somewhere between 60-90 cases reported in the literature. Metastatic carcinoid tumor from the gastrointestinal tract to the liver is far more common.
Some patients present with carcinoid syndrome...
Hepatic carcinosarcoma is a very rare tumor that is defined by mixed histological features.
This tumor has also been referred to as malignant mixed tumor, spindle cell carcinoma, pseudosarcoma or sarcomatoid carcinoma 1,2.
Hepatic carcinocarcinoma contain a mixture of...
Hepatic encephalopathy (HE), also known as portosystemic encephalopathy (PSE), refers to a spectrum of neuropsychiatric abnormalities occurring in patients with liver dysfunction and portal hypertension. It results from exposure of the brain to excessive amounts of ammonia.
Hepatic epithelioid hemangioendothelioma (HEHE) is a rare, low to intermediate grade malignant hepatic vascular tumor.
There may be a greater female incidence (with reported male-to-female ratio, 3:2), with peak incidence thought to be around 30-40 years old.
Hepatic hemangiomas are 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 malignancy.
Hepatic hemangiomas ar...
Hepatic haemangiomatosis is a condition in which the are multiple hemangiomas affecting the liver.
When the lesions are spread throughout the liver, then this is termed diffuse hepatic haemangiomatosis.
giant liver hemangioma 2
Hepatic hemosiderosis, or hepatic iron overload, refers to the deposition of hemosiderin in the liver.
Hepatic iron overload can be in the form of 7:
In the absence of genetic he...
Hepatic hydatid disease a parasitic zoonosis caused by the Echinococcus tapeworm. In the liver, two agents are recognized as causing disease in humans:
For a general discussion, and for links to other system-specific manifestations, please ...
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 characterized by formation of pleural effusions usually greater than 500 mL, in patients with portal hypertension without any o...
Hepatic infarction is an extremely rare situation because the liver has a dual blood supply from 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.
Hepatic inflammatory pseudotumors (IPT) are rare benign hepatic lesions.
Most common in young adults with males affected more than females 7.
Etiology is unknown 7.
Hepatic IPT is often seen as a well-circumscribed, encapsulated inflammatory ...
Hepatic leiomyosarcomas are rare primary malignant tumors derived from smooth muscle cells in the liver.
Hepatic leiomyosarcoma is rare 1. An equal sex distribution and a broad age range (5 months-66Y) has been reported. Some have suggested an associated with AIDS 2.
Hepatic lipomas are uncommon benign lesions of the liver.
As with lipomas elsewhere in the body, hepatic lipomas are marginated masses which are composed of mature adipocytes without evidence of cellular atypia.
Histopathologic evaluation may reveal adenomatous, angiomatous or myoma...
Hepatic lymphangiomas are a rare benign condition that corresponds to focally dilated lymphatic channels in the liver.
For a general discussion on this topic, please refer to the parental article on lymphangioma.
Most cases are asymptomatic.
A lymphangioma ...
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
Risk factors f...
Hepatic mesenchymal hamartoma are uncommon benign hepatic lesions which are mostly seen in children under the age of 2. Some authors consider them to be developmental anomalies rather than cystic neoplasia 9,12.
typically occurs in children and neonates 3
most cases present...
Hepatic metastases are 18-40 times more common than primary liver tumors 6. Ultrasound, CT, and MRI are all useful for detection of hepatic metastases and evaluation across multiple post-contrast CT series, or MRI pulse sequences are necessary.
The demographics of patients with l...
Hepatic myeloid sarcomas, also referred to as hepatic granulocytic sarcoma or hepatic chloromas, are rare neoplasms comprised of myeloid precursor cells happening in the liver. They are commonly associated with acute myeloid leukemia (AML), but they may also occur with other myeloproliferative a...
Hepatic osteodystrophy is an often forgotten metabolic bone disease seen in patients with chronic liver disease, in particular cirrhosis, primary biliary cirrhosis, and primary sclerosing cholangitis. These patients have increased risk factors for developing osteoporosis such as hypogonadism, al...
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 m...
Hepatic pseudolesions near the falciform ligament show abnormal attenuation without mass effect. They may be seen on contrast-enhanced CT scans as either a region of high or low attenuation relative to the rest of the liver. They are typically located in the medial segment of the left lobe of th...
Hepatic siderotic nodules are a type of regenerative nodule formed in a cirrhotic liver. They occur in hepatic hemosiderosis. The nodules have an increased iron content compared with other regenerative nodules. They may be non-dysplastic or dysplastic.
The reason why these nodules co...
Hepatic solitary fibrous tumors (hepatic SFTs) are rare mesenchymal tumors.
Fewer than 60 cases have been reported in the literature. Female predominance (~70%). There is a mean age of 52 years at presentation, but a wide range of incidence (16-84 years).
Hepatic steatosis refers to an increase of intracellular fat in the liver. It is widely mischaracterized by both radiologists and sonographers as 'fatty infiltration' but the fat is in the hepatocytes and not in the extracellular matrix. On imaging grounds, it can broadly be divided into two gro...
Hepatic vascular and perfusion disorders are a broad group of conditions that radiologists should be familiar with, as some of them are quite frequently seen in the daily practice. The aim of this article is to be a collection of articles that represent the core knowledge in the matter.
The hepatic veins are three large intraparenchymal veins which drain the liver substance into the inferior vena cava (IVC), named the right hepatic vein, middle hepatic vein and left hepatic vein. The veins are important landmarks, running in between and hence defining the segments of the liver....
Hepatic veno-occlusive disease (VOD), also known as sinusoidal obstruction syndrome (SOS), is a condition arising from occlusion of hepatic venules.
right upper quadrant pain
abnormal liver function tests
Toxic injury to liver s...
Hepatic venous pressure gradient measurement is a safe and minimally invasive method to indirectly measure portal vein pressure in chronic liver disease patients suspected of developing portal vein hypertension.
diagnosis of liver fibrosis and risk stratification
Hepatisation of the gallbladder is a sonographic entity in which the gallbladder lumen is entirely filled with tumefactive sludge giving the gallbladder a similar appearance to liver parenchyma. It is one of the causes of non-visualization of the gallbladder on sonography.
In the set...
Hepatitis B virus (HBV) is a circular DNA virus endemic in many parts of the world. It is a risk factor for the development of hepatocellular carcinoma (HCC).
Acute HBV infection is most often subclinical and asymptomatic. Symptomatic patients (~33%) may experience fever,...
Hepatitis C virus (HCV) is an RNA virus and a member of the Flaviviridae family. It is a risk factor for the development of hepatocellular carcinoma (HCC).
Route of transmission
The most common route of transmission is through blood products and contaminated needles. Unprotected sex...
LI-RADS (Liver Imaging Reporting and Data System) is both a set of standardized terminology and a classification system for imaging findings in liver lesions. The LI-RADS score for a liver lesion is an indication of its relative risk for hepatocellular carcinoma (HCC). The classification system ...
Hepatobiliary imaging in nuclear medicine can be accomplished with multiple different radiotracers to help evaluate the liver, gallbladder and the biliary ducts. The choice of tracer depends on the clinical question.
Common tracers include:
Tc-99m IDA (iminodiacetic acid) analogs: most commonl...
Hepatobiliary MRI contrast agents are specialized contrast agents used to aid diagnosis in MRI.
They are separated into three categories: gadolinium-based agents, manganese-based agents and superparamagnetic iron oxide particles.
Gadolinium (Gd) based contrast agents ...
The hepatobiliary system consists of the:
biliary tree (both intra- and extra-hepatic)
The pancreas is included by some.
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 tumor of embryonic origin.
Most cases are seen during the first 18 months of life and diagnosis in adulthood i...
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.
As expected there are a number of different staging systems for hepatoblastoma.
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 ...
Hepatocellular carcinoma (HCC) is the most common primary malignancy of the liver. It is strongly associated with cirrhosis, from both alcohol and viral etiologies. HCC constitutes approximately 5% of all cancers partly due to the high endemic rates of hepatitis B infection 1.
Hepatocellular carcinoma staging classifications supersede the typical TNM staging system seen in most other epithelial cancers, as the TNM staging system has been found to not be as prognostically useful for stratification of patients with hepatocellular carcinoma. Several substitute staging sy...
Hepatocellular carcinoma surveillance programs have been adopted by some health systems in attempts to effect an early diagnosis of hepatocellular carcinoma in high-risk populations.
The idea behind hepatocellular carcinoma screening, as with any screening program, is to detect clin...
The hepatoduodenal ligament is a peritoneal ligament of lesser omentum containing the portal triad. 1
The hepatoduodenal ligament is a thickening of the right edge of the lesser omentum and forms the anterior margin of the epiploic foramen. It extends from the porta hepatis to th...