Articles
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More than 200 results
Article
Amoebic hepatic abscess
Amoebic hepatic abscesses are a form of hepatic abscess resulting from Entamoeba histolytica infection.
Epidemiology
The parasite causes up to 40 million infections annually, up to 100,000 deaths per annum 7,8. However, clinical disease only presents in a minority of patients 8.
Although the...
Article
Gangrenous cholecystitis
Gangrenous cholecystitis is the most common complication of acute cholecystitis, affecting ~15% (range 2-30%) of patients.
Epidemiology
Risk factors
male
increasing age
delayed surgery
cardiovascular disease
diabetes mellitus
systemic inflammatory response syndrome 5
Pathology
Gangren...
Article
Prolonged heterogeneous liver enhancement (CEUS)
Prolonged heterogeneous liver enhancement (PHLE), also informally termed as the "disappearing liver" phenomenon, is a very rare, benign complication of ultrasound contrast media, of unknown etiology 1. PHLE manifests itself as confluent, rapidly appearing hyperechoic foci in the liver, that may ...
Article
Hematopoietic stem cell transplantation (abdominal complications)
Abdominal complications of hematopoietic stem cell transplantation can occur early (0-100 days) or late (>100 days) post-transplant.
Complications
Early
bacterial infections, e.g. pseudomembranous colitis
fungal infections, often affecting the esophagus or as hepatic/splenic microabscesses
...
Article
Biliary tree anatomy
The biliary tree is a branching system of ducts that delivers bile produced in the hepatic parenchyma toward the gallbladder and duodenum.
Gross anatomy
By convention the biliary tree is divided into intra- and extra-hepatic bile ducts 1. There is significant variation in the anatomy of the bi...
Article
Vicarious contrast media excretion
Vicarious contrast media excretion (VCME) refers to the excretion of intravascularly-administered water-soluble iodinated contrast media in a way other than via normal renal excretion. More rarely it may occur following oral contrast medium administration 6.
Epidemiology
The most common vicari...
Article
Accessory right inferior hepatic vein
An accessory right inferior hepatic vein is the most common variation of the hepatic veins, and may be multiple 1. It is present in up to 48% of the population and drains the posteroinferior part of the right lobe directly into the inferior vena cava (IVC) 1-3.
Variations in hepatic vascular an...
Article
Cardiac sclerosis
Cardiac sclerosis or cardiac cirrhosis is the end-point of passive hepatic congestion from heart failure.
Pathology
Etiology
Causes of cardiac cirrhosis include 1:
ischemic heart disease: ~30%
cardiomyopathy: ~25%
valvular heart disease: ~25%
restrictive lung disease: ~15%
pericardial d...
Article
Paraduodenal pancreatitis
Paraduodenal pancreatitis is an uncommon type of focal chronic pancreatitis affecting the groove between the head of the pancreas, the duodenum and the common bile duct.
Terminology
The following entities with which it shares clinicopathological features are unified by this term and should no ...
Article
Complications of radiation therapy
Radiation therapy has the potential to cause complications in many organ systems, many of which, especially in the thorax, are important for radiologists to be aware of.
acute radiation syndrome
complications of cranial radiation therapy
radiation-induced cerebral vasculopathy
radiation-ind...
Article
Enlarged hilar periportal space sign
The enlarged hilar periportal space sign refers to the widening of the periportal space seen on MRI in early liver cirrhosis.
Usage
Enlarged hilar periportal space sign is one of the early signs of cirrhosis and may be used to detect fibrotic changes in the liver in patients who do not yet hav...
Article
Hepatic atrophy
Hepatic atrophy is a common appearance on imaging of the liver. It may result from obstruction of a major branch of the portal vein, bile ducts or hepatic veins. It does not usually occur secondary to hepatic arterial flow compromise. Compensatory hypertrophy of the unaffected segments/lobes is ...
Article
Inferior vena cava web
Inferior vena cava (IVC) webs are an uncommon condition characterized by obstruction of the hepatic segment of the inferior vena cava by a membrane or fibrous band. This is often associated with occlusion of one or more of the hepatic veins.
Clinical presentation
If there is hepatic vein invol...
Article
Lollipop sign (hepatic epithelioid hemangioendothelioma)
The lollipop sign is seen in hepatic epithelioid hemangioendothelioma (HEHE). It represents hepatic/portal vein and/or their tributaries/branches tapering and terminating at or just within the edge of a well defined peripherally enhancing (or non-enhancing) lesion with an avascular core on CT or...
Article
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 the dilation of central hepatic veins and hepatomegaly.
Passive hepatic congestion is a well-studied re...
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
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
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
Right hepatic artery
The right hepatic artery (RHA) is formed when the proper hepatic artery (PHA) bifurcates. The hepatic arteries provide 25% of the blood supply and 50% of the oxygen supply to the liver.
Gross anatomy
The proper hepatic artery bifurcates into the right and left hepatic arteries at or before rea...
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...