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.
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1,095 results found
Article
Aphthoid ulceration
Aphthoid ulcers are shallow ulcers of the gastrointestinal mucosa.
Pathology
Etiology
infective inflammatory conditions
Yersinia enterocolitis
amoebic enterocolitis
cytomegalovirus enterocolitis
noninfective inflammatory conditions
Crohn disease
idiopathic granulomatous gastritis
vascu...
Article
Appendiceal carcinoid
Appendiceal carcinoids are rare overall but represent the most common tumor of the appendix. The appendix is also one of the most common (but not the most common) locations for gastrointestinal carcinoid tumors.
Clinical presentation
Appendiceal carcinoids can present as the obstructive cause...
Article
Appendiceal diverticulitis
Appendiceal diverticulitis is a rare condition in which there is acute inflammation of a diverticulum arising from the vermiform appendix.
Epidemiology
Historically appendiceal diverticulitis has been thought to be a rare diagnosis. However a study from 2015 which retrospectively reviewed the ...
Article
Appendiceal intussusception
Appendiceal intussusception happens when appendix segment is pulled into itself or into the cecum. This condition can mimic various chronic and acute abdominal conditions. It is an important entity to recognize since it could be mistaken for a cecal mass.
Epidemiology
Appendiceal intussuscepti...
Article
Appendiceal mucocele
Appendiceal mucoceles occur when there is an abnormal accumulation of mucin causing abnormal distention of the vermiform appendix due to various neoplastic or non-neoplastic causes.
Epidemiology
The reported prevalence at appendectomy is 0.2-0.3%. They are thought to typically present in middl...
Article
Appendicitis
Appendicitis is inflammation of the vermiform appendix. It is a very common condition in general radiology practice and is one of the main reasons for abdominal surgery in young patients. CT is the most sensitive modality to detect appendicitis.
Epidemiology
Acute appendicitis is typically a d...
Article
Appendicitis (summary)
This is a basic article for medical students and other non-radiologists
Appendicitis occurs when there is inflammation of the vermiform appendix. It is a very common condition and is a major cause of abdominal surgery in young patients. CT is the most sensitive modality to detect appendicitis a...
Article
Appendicolith
An appendicolith is a calcified deposit within the appendix. They are present in a large number of children with acute appendicitis and may be an incidental finding on an abdominal radiograph or CT. Incidence may be increased among patients with a retrocaecal appendix. Overall they are seen in 1...
Article
Appendicular abscess
Appendicular abscess is considered the most common complication of acute appendicitis, in particular after a perforated appendix.
Radiographic features
Appendicular abscesses can arise either in the peritoneal cavity or the retroperitoneal space.
Ultrasound
Ultrasound is the first investiga...
Article
Appendicular artery
The appendicular artery is a branch of the ileal or posterior cecal branch of the ileocolic artery, which is from the superior mesenteric artery.
It courses posteriorly to the terminal ileum in the free wall of the mesoappendix to supply the appendix.
Article
Appendix
The appendix or vermiform appendix is a blind muscular tube that arises from the cecum, which is the first part of the large bowel.
Gross anatomy
The appendix arises from the posteromedial surface of the cecum, approximately 2-3 cm inferior to the ileocecal valve, where the 3 longitudinal band...
Article
Appleby procedure
The Appleby procedure is a type of pancreatic cancer resection.
For some patients with pancreatic cancer involving the body and tail of the pancreas, involvement of the celiac axis is a classic contraindication to pancreaticoduodenectomy (Whipple procedure).
With the Appleby procedure, there...
Article
Apple core sign (colon)
The apple core sign, also known as a napkin ring sign (bowel), is most frequently associated with constriction of the lumen of the colon by a stenosing annular colorectal carcinoma.
Differential diagnosis
The appearance of the apple-core lesion of the colon also can be caused by other diseases...
Article
Apple-peel intestinal atresia
Apple-peel intestinal atresia, also known as type IIIb or Christmas tree intestinal atresia, is a rare form of small bowel atresia in which the duodenum or proximal jejunum ends in a blind pouch and the distal small bowel wraps around its vascular supply in a spiral resembling an apple peel. Oft...
Article
Arc of Buhler
The arc of Buhler (AOB) is a persistent embryonic anastomotic branch between the 10th and 13th ventral segmental arteries, resulting in a connection between the celiac artery and superior mesenteric artery (SMA). This arch is independent of both the gastroduodenal and dorsal pancreatic artery.
...
Article
Arc of Riolan
The arc of Riolan, also known as the mesenteric meandering artery (of Moskowitz) or central anastomotic mesenteric artery, is an arterioarterial anastomosis between the superior and inferior mesenteric arteries.
Gross anatomy
It is an inconstant artery that connects the proximal superior mesen...
Article
Areae gastricae
Areae gastricae are a normal finding on double contrast images of the stomach.
Radiographic features
fine reticular network of barium-coated grooves between 1-5 mm islands/areas of gastric mucosa
may be seen in ~70-80% of patients if there is adequate high-density barium coating of the stomac...
Article
A-rings (esophagus)
A-rings are a type of distal esophageal ring. They are above the B-ring and occur a few centimeters proximal to the gastro-esophageal junction. They represent a physiological contraction of esophageal smooth muscle covered by mucosa. A-rings are uncommonly symptomatic.
Article
Arrowhead sign (cecum)
The arrowhead sign refers to the focal cecal thickening centred on the appendiceal orifice, seen as a secondary sign in acute appendicitis. The contrast material in the cecal lumen assumes an arrowhead configuration, pointing at the appendix.
The arrowhead sign is applicable only when enteric...
Article
Asbestos related diseases
Asbestos related disease, in particular affecting the lung, comprise of a broad spectrum of entities related to the inhalational exposure to asbestos fibers. They can be divided into benign and malignant changes 1-3.
Benign pleural and parenchymal lung disease
asbestos related benign pleural d...
Article
Ascariasis
Ascariasis is due to infection with the Ascaris lumbricoides adult worm and typically presents with gastrointestinal or pulmonary symptoms, depending on the stage of development.
Epidemiology
Ascaris lumbricoides is widely distributed in tropical and subtropical regions and in other humid ar...
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...
Article
Ascending colon
The ascending colon is the second part of the large bowel.
Gross anatomy
The ascending colon is the continuation of the cecum superior to the ileocecal valve. It is secondarily retroperitoneal, although it has its own mesentery in approximately 25% of patients and is 15 cm in length 1,2.
The ...
Article
Ascites
Ascites is defined as an abnormal amount of intraperitoneal fluid.
Clinical presentation
Patients with a large volume of ascites can present with abdominal distension (which may be painful), nausea, vomiting, dyspnea and peripheral edema 7, 9.
Pathology
Ascitic fluid is traditionally charact...
Article
Asplenia
Asplenia refers to absence of the spleen thereby leading to deficient splenic function.
Epidemiology
Seen in 3% of neonates with structural heart disease and in 30% of patients who die from cardiac malposition. The male-to-female ratio is 2:1.
Pathology
Asplenia can be classified into two t...
Article
Atrial-esophageal fistula
Atrio-esophageal fistulas are rare pathological connections between the left atrium and the esophagus.
Clinical presentation
The presentation is non-specific. Patients may complain of fever, malaise, and/or dysphagia, or present with neurological symptoms 3.
Pathology
The chief cause of at...
Article
Atrophic gastritis
Atrophic gastritis is a chronic condition of autoimmune and non-autoimmune etiology.
Pathology
Two types of atrophic gastritis have been described 1-3:
type A: autoimmune
gastric body and fundus atrophy secondary to antiparietal cell antibodies
decreased secretion of acid and intrinsic fac...
Article
Autoimmune pancreatitis
Autoimmune pancreatitis (AIP) is a form of chronic pancreatitis associated with autoimmune manifestations on clinical, histological, and laboratory grounds 1.
Distinguishing this entity from other forms of chronic pancreatitis (such as alcohol-induced) is important as steroid treatment is effec...
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 septicaemia 1, and SLE 2. The demographics t...
Article
Backwash ileitis
Backwash ileitis is seen in patients with ulcerative colitis (UC), where the entire colon is involved. In such cases the terminal ileum is edematous.
Backwash ileitis extends contiguously backward from the cecum without skip regions. One source estimates it to occur in 6% of patients with UC, a...
Article
Ball of wool sign (hydatid cyst)
The ball of wool sign, also referred to as the yarn sign or congealed water lily sign, is an ultrasound appearance, representing degeneration of hydatid cysts (WHO class CE 4). The inner side of the cyst detaches from the cyst wall and folds on itself, causing a change from anechoic (fluid) to a...
Article
Balloon-occluded retrograde transvenous obliteration
Balloon-occluded retrograde transvenous obliteration (BRTO) is a technique used by interventional radiologists in the treatment of gastric varices, particularly those with prominent infra-diaphragmatic portosystemic venous shunts (e.g. gastro-renal and gastro-caval shunts).
The technique is mor...
Article
Balthazar score
The Balthazar score is a subscore within the CT severity index (CTSI) for grading of acute pancreatitis.
The CTSI sums two scores:
Balthazar score: grading of pancreatitis (A-E)
grading the extent of pancreatic necrosis
The Balthazar score was originally used alone, but the addition of a sc...
Article
Bannayan–Riley–Ruvalcaba syndrome
Bannayan–Riley–Ruvalcaba syndrome (BRRS or BRR syndrome) is a very rare autosomal dominant hamartomatous disorder caused by a mutation in the PTEN gene. It is considered in the family of hamartomatous polyposis syndrome.
There are no formal diagnostic criteria for this disease, but characterist...
Article
Bariatric intragastric balloon therapy
Bariatric intragastric balloon therapy is a relatively new form of weight loss therapy, which involves a balloon being endoscopically-placed or swallowed and inflated inside the lumen of the stomach. The balloon resides in the stomach and the mechanism of action is presumably due to stretching t...
Article
Barium peritonitis
Barium peritonitis is a rare complication of gastrointestinal fluoroscopy, and occurs when there is gastrointestinal tract perforation and spillage of barium into the peritoneal cavity.
Pathology
Barium in the peritoneal cavity is treated as a foreign body with resultant immune response that ...
Article
Barium studies of the small bowel
Barium studies of the small intestine are still considered an effective modality to show the bowel loops in a cost-effective way.
Procedure
Small bowel follow through (SBFT) or transit study
routine investigation for delineation of all parts the small bowel
done with barium meal after havin...
Article
Barium sulfate
Barium sulfate (BaSO4), often just called barium in radiology parlance, is a salt of barium (Ba), a metallic chemical element with atomic number 56. Barium is considered one of the heavy metals. Unlike barium and many of its other salts, barium sulfate is insoluble in water and therefore very li...
Article
Barium swallow
Barium swallow is a dedicated test of the pharynx, esophagus, and proximal stomach, and may be performed as a single or double contrast study. The study is often "modified" to suit the history and symptoms of the individual patient, but it is often useful to evaluate the entire pathway from the ...
Article
Barrett esophagus
Barrett esophagus is a term for intestinal metaplasia of the esophagus. It is considered the precursor lesion for esophageal adenocarcinoma.
Epidemiology
Barrett esophagus is thought to have a prevalence of 3-15% in patients with reflux esophagitis. Mean age at diagnosis is 55 years old 5. Ris...
Article
Beak sign (pyloric stenosis)
Beak sign in pyloric stenosis is one of the fluoroscopic (barium meal) findings which is useful in the diagnosis of congenital hypertrophic pyloric stenosis.
Radiographic features
Barium meal
A beak-like tapering projection of barium is seen entering into the narrowed and compressed pyloric ...
Article
Behçet disease
Behçet disease is a multisystemic and chronic inflammatory vasculitis of unknown etiology.
Epidemiology
The mean age at which Behçet disease occurs is 20-30 years. The disease is most prevalent in the Mediterranean region, Middle East and East Asia. The highest incidence has been reported in T...
Article
Benign esophageal lesions
Benign esophageal lesions are less symptomatic than malignant esophageal lesions, making up for only 1% of clinically apparent esophageal lesions.
Pathology
esophageal leiomyoma (>50%)
may calcify
esophageal fibrovascular polyp (~12.5%)
may contain fat
esophageal duplication cyst (10%)
oe...
Article
Benign post-traumatic pseudopneumoperitoneum
Benign post-traumatic pseudopneumoperitoneum is the presence of ectopic gas typically between the 5th-10th intercostal spaces after high-energy trauma in the absence of other causes of pseudopneumoperitoneum such as pneumomediastinum 9.
Epidemiology
Occurs with an incidence of 5% post-trauma...
Article
Bethesda criteria of hereditary non-polyposis colorectal cancer
The Bethesda criteria are an alternative to the Amsterdam criteria for the clinical diagnosis of hereditary non-polyposis colorectal cancer (HNPCC).
Diagnosis of HNPCC is made if any of the following criteria are fulfilled:
Amsterdam criteria are met
2 or more HNPCC related malignancies
pa...
Article
Bezoar
Bezoars are accumulations of indigestible contents within the gastrointestinal tract 2.
Pathology
There are several types depending on the predominant components:
trichobezoar: a bezoar formed from hair, this has also been called Rapunzel syndrome when the tail of the trichobezoar extends so...
Article
Bilateral adrenal gland hyperenhancement
Bilateral adrenal gland hyperenhancement or intense adrenal enhancement may be a feature of hypotension and forms part of the CT hypoperfusion complex.
Adrenal gland hyperenhancement has been described in pediatric and small adult series or individual cases of hemorrhagic shock, pancreatitis, s...
Article
Biliary cast syndrome
Biliary cast syndrome is a complication that occurs after liver transplantation, where dark solid bilirubin casts develop in the biliary tree, causing biliary obstruction.
Terminology
This should be differentiated from biliary sludge, which represents thickened bile that has not precipitated.
...
Article
Biliopancreatic diversion
Biliopancreatic diversion was a development on the jejunoileal bypass type of bariatric surgery. It can be performed with or without a duodenal switch.
The procedure involves
distal gastrectomy, with formation of a gastric pouch
gastroenterostomy, with formation of a ~250 cm Roux limb (normal...
Article
Billroth II gastrojejunostomy
Billroth II gastrojejunostomy is a procedure that has been performed for tumor or severe ulcer disease in the distal stomach.
There are many variations on the procedure, but they generally involve resection of the diseased portion of the distal stomach and a side-to-side anastomosis of the resi...
Article
Bird beak sign (esophagus)
The bird's beak sign of the esophagus is used to refer to the tapering of the inferior esophagus in achalasia. The same appearance (although it is difficult to see the similarity) is also referred to as the rat-tail sign.
The appearance, although classically occurring in primary achalasia, can ...
Article
Bird beak sign (right colon)
The bird beak sign of the right colon is tapering obstruction of the inferior part of right colon seen on contrast enema or CT scan with rectal contrast indicating cecal volvulus.
This sign can help to differentiate cecal volvulus from cecal bascule, in particular on a contrast/barium enema stu...
Article
Bird beak sign (sigmoid colon)
Bird's beak sign of the sigmoid is one of the signs of sigmoid volvulus. It represents gradual narrowing/tapering of sigmoid colon up to the level of obstruction during contrast/barium insertion to the rectum or on CT.
When located in the sigmoid colon, it suggests the diagnosis of sigmoid volv...
Article
Blind loop syndrome
Blind loop syndrome (or "blind pouch syndrome") is an event that may occur after an end-to-end or end-to-side bowel anastomosis. Dilatation and stasis of the bypassed bowel may lead to bacterial overgrowth, breakdown of bile salts, and result in nutritional problems. It may even eventually lead ...
Article
Bochdalek hernia features (mnemonic)
A helpful mnemonic for remembering the features of a Bochdalek hernia is:
5 Bs
Mnemonic
B: Bochdalek
B: big
B: back and medial, usually on the left side
B: baby
B: bad (associated with pulmonary hypoplasia)
Article
Body packing
Body packing refers to the internal concealment of drugs within the gastrointestinal tract or other orifices. People who do this may be called body packers, (drug) mules, stuffers, couriers or swallowers. Drugs may be concealed within condoms, foil, latex or cellophane.
Epidemiology
There is ...
Article
Boerhaave syndrome
Boerhaave syndrome refers to an esophageal rupture secondary to forceful vomiting and retching.
Epidemiology
It tends to be more prevalent in males, with alcoholism a risk factor. The estimated incidence is ~ 1:6000.
Clinical presentation
They are often associated with the clinical triad (Ma...
Article
Bouveret syndrome
Bouveret syndrome refers to a gastric outlet obstruction secondary to impaction of a gallstone in the pylorus or proximal duodenum. Thus, it can be considered a very proximal form of gallstone ileus.
Clinical presentation
Bouveret syndrome occurs most commonly in elderly women. The presenting...
Article
Bowel and mesenteric trauma
Bowel and mesenteric trauma can result from blunt force, penetrating and iatrogenic trauma.
Epidemiology
The bowel and mesentery are injured in ~2.5% (range 0.3-5%) of blunt force abdominal trauma 1,3,5,8. However not surprisingly, bowel and mesenteric injuries are more frequent after penetrat...
Article
Bowel dilatation (summary)
This is a basic article for medical students and other non-radiologists
Bowel dilatation is a relatively non-specific sign than can be seen on most imaging modalities. In bowel obstruction, dilatation may be demonstrated on a plain radiograph providing the bowel is filled with gas.
Reference a...
Article
Bowel obstruction
Bowel obstructions are common and account for 20% of admissions with "surgical abdomens". Radiology is important in confirming the diagnosis and identifying the underlying cause.
Bowel obstructions are usually divided according to where the obstruction occurs, and since imaging appearances, und...
Article
Bowel perforation
Bowel perforation can occur in many different settings, but the more common are
bowel obstruction (both small and large)
bowel ischemia
severe ulcer disease
diverticular disease
infection
malignant diseases
gastrointestinal tumors
direct tumor invasion
trauma: blunt or penetrating
auto...
Article
Bowel perforation (summary)
This is a basic article for medical students and other non-radiologists
Bowel perforation is an acute surgical emergency where there is a release of gastric or intestinal contents into the peritoneal space.
Reference article
This is a summary article; read more in our article on bowel perfora...
Article
Bowel sacculation (mnemonic)
A mnemonic to remember causes of bowel sacculation is:
MISC
Mnemonic
M: metastasis
I: ischemia
S: scleroderma
C: Crohn disease
Article
Bowel wall thickening
Bowel wall thickening is a useful finding on imaging studies and has a number of different causes.
Pathology
The reason for bowel wall thickening depends on the underlying etiology but includes submucosal edema, hemorrhage, and neoplastic infiltration.
Radiographic features
In describing bow...
Article
Bronchogenic cyst vs esophageal duplication cyst
Bronchogenic cysts and esophageal duplication cysts are embryological foregut duplication cysts and are also differential diagnoses for a cystic mediastinal mass.
Differences
Symptoms
asymptomatic bronchogenic cyst
symptomatic esophageal cyst in the case of peptic ulceration
Plain radiograp...
Article
Brunner gland adenoma
Brunner gland adenomas are hyperplastic areas of the Brunner glands within the duodenum that are greater than 1 cm. They tend to be 1-2 cm in diameter, although case reports have described tumors of up to 12 cm diameter. Where the diameter of focal hyperplasia is less than 1 cm, the term Brunner...
Article
Brunner gland hyperplasia
Brunner gland hyperplasia results from disproportionate overgrowth of Brunner glands in the duodenum as a result of hyperacidity.
Hyperplasia begins at the pylorus and extends distally within the first 2/3rds of the duodenum. Where the focal growth of hyperplastic cells is greater than 1 cm in ...
Article
Brunner glands
Brunner glands are compound tubular submucosal glands found in the duodenum. They are only found proximal to the sphincter of Oddi.
Related pathology
Brunner gland hyperplasia
Brunner gland adenoma
Article
Bulging duodenal papilla
Major duodenal papilla is a conic or cylindric protuberance at the medial aspect of the descending or horizontal duodenum at the site of the sphincter of Oddi. It is finding on small bowel follow-though (and endoscopy) and has a relatively long differential.
On cross sectional imaging, the unde...
Article
Buried bumper syndrome
Buried bumper syndrome (BBS) is a rare but important complication in patients with a percutaneous gastrostomy tube, occurring by migration of the internal bumper along its track. The tube may get lodged anywhere between the gastric wall and the skin and lead to life-threatening complications inc...
Article
CA 19-9
CA 19-9 (carbohydrate antigen 19-9 or cancer antigen 19-9) is a serum antigen (monosialoganglioside) that has increased diagnostic use in the management of several malignancies, mainly of hepatopancreaticobiliary origin. It is non-specific, however, and can rise in both malignant and non-maligna...
Article
Cecal bar sign
The cecal bar sign is a secondary sign in acute appendicitis. It refers to the appearance of inflammatory soft tissue at the base of the appendix, separating the appendix from the contrast-filled cecum.
See also
arrowhead sign
Article
Cecal bascule
Cecal bascule is an uncommon type of cecal volvulus in which the cecum folds up over itself in an anteromedial orientation. In contrast to the more common forms of volvulus, there is no axial "twisting" component 4. A cecal bascule may occur in the setting of a large and mobile cecum and can re...
Article
Cecal volvulus
Cecal volvulus describes torsion of the cecum around its mesentery which often results in obstruction. If unrecognised, it can result in bowel perforation and fecal peritonitis.
Epidemiology
Cecal volvulus accounts for ~10% of all intestinal volvuluses, and generally occur in somewhat younger ...
Article
Cecum
The cecum is the first part of the large bowel and lies in the right lower quadrant of the abdomen.
Gross anatomy
Blind-ending sac of bowel that lies below the ileocecal valve, above which the large intestine continues as the ascending colon. The cecum measures 6 cm in length and can have a m...
Article
Candida esophagitis
Candida esophagitis is the most common cause of infectious esophagitis that commonly affects immunocompromised patients. On imaging, it is characterized by irregular plaque-like lesions separated by normal mucosa and small (<1cm) ulcers, which are assessed on esophagogram studies.
Epidemiolog...
Article
Cantlie's line
Cantlie's line is a vertical plane that divides the liver into left and right lobes creating the principal plane used for hepatectomy. It extends from the inferior vena cava posteriorly to the middle of the gallbladder fossa anteriorly.
It contains the middle hepatic vein which divides the live...
Article
Carbolic acid poisoning symptoms (mnemonic)
The symptoms of carbolic acid poisoning can be recalled using the mnemonic:
5 Cs
Mnemonic
C: CNS depression
C: constricted pupil
C: carboluria (smoky urine)
C: cartilage
C: corneal deposition
Article
Carcinoembryonic antigen
Serum carcinoembryonic antigen (CEA) is a cell-adhesive glycoprotein that was discovered in colorectal cancer in 1965, and is hence one of the oldest and most used tumor markers. Its name derives from its normal expression in fetoembryonic liver, gut and pancreas tissue.
Normal range of CEA is ...
Article
Carcinogens
Carcinogens are substances known to cause cancer. They include:
Brain
vinyl chloride
Nasopharynx / nasal passage
nickel
wood dust
chromium
Thyroid
ionising radiation (not technically a substance)
Skin
arsenic
coal tars
polyaromatic hydrocarbons (PAH)
Lungs
arsenic
asbestos
chloro...
Article
Carcinoid syndrome
Carcinoid syndrome refers to a spectrum of symptoms that result from excessive hormone (mainly serotonin) secretion.
Epidemiology
Occurs equally between the sexes, most commonly in the 40-70 year age group 3.
Clinical presentation
Diarrhea is the most common and earliest symptom but others ...
Article
Carcinoid tumor
Carcinoid tumors are a type of neuroendocrine tumor that can occur in a number of locations. Carcinoid tumors arise from endocrine amine precursor uptake and decarboxylation (APUD) cells that can be found throughout the gastrointestinal tract as well as other organs (e.g. lung). In general, they...
Article
Carcinosarcoma
Carcinosarcomas are highly malignant biphasic tumors with both carcinomatous (epithelial) and sarcomatous (bone, cartilage, or skeletal muscle) components.
Pathology
It can arise in many organs:
lung 5: pulmonary carcinosarcoma
esophagus 1: esophageal carcinosarcoma
genitourinary tract 2
...
Article
Carman meniscus sign
The Carman meniscus sign describes the lenticular shape of barium in cases of large and flat gastric ulcers, in which the inner margin is convex toward the lumen. It usually indicates a malignant ulcerated neoplasm; in cases of benign gastric ulcers, the inner margin is usually concave toward th...
Article
Carney-Stratakis syndrome
Carney-Stratakis syndrome is a rare autosomal dominant condition comprising of familial paraganglioma and gastric stromal sarcoma.
Terminology
It is considered to be distinct from, but perhaps related to, the Carney triad 1. Neither should be confused with the unrelated Carney complex.
Histor...
Article
Carney triad
The Carney triad is a rare syndrome defined by the coexistence of three tumors:
extra-adrenal paraganglioma (e.g. spinal paraganglioma)
initially, only functioning extra-adrenal paragangliomas were included, but subsequent work includes non-functioning extra-adrenal paragangliomas 1
gastric g...
Article
Cases in radiology (video tutorials)
The cases featured in these video lectures are specifically selected to teach important concepts in radiology over a broad range of topics. The tutorials vary in difficulty from basic to advanced. For maximum learning, try the cases for yourself in Radiopaedia quiz mode first.
We love this ser...
Article
Casoni skin test
The Casoni skin test is a hypersensitivity based skin test used to detect hydatid disease. Although once a major test in diagnosing hydatid disease it has largely been superseded by newer more sensitive, specific and safer serological tests.
Technique
Sterile fluid (0.25 mL) of hydatid cyst or...
Article
Castleman disease
Castleman disease, also known as angiofollicular lymph node hyperplasia or giant lymph node hyperplasia, is an uncommon benign B-cell lymphoproliferative condition. It can affect several regions of the body although commonly described as a solitary mediastinal mass.
There are two distinct subty...
Article
Caterpillar sign
The caterpillar sign is a radiological sign described in pyloric stenosis.
It refers to the appearance of stomach on an upper gastrointestinal radiographic series or plain abdominal radiograph 1,2. On these imaging modalities in a patient with pyloric stenosis, the stomach appears distended, ai...
Article
Causes of pancreatitis (mnemonic)
A catchy and early learnt mnemonic for recalling some of the causes of pancreatitis is:
I GET SMASHED
Mnemonic
I: idiopathic
G: gallstones, genetic - cystic fibrosis
E: ethanol (alcohol)
T: trauma
S: steroids
M: mumps (and other infections)/malignancy
A: autoimmune
S: scorpion stings/s...
Article
Cavernous venous malformation
Cavernous venous malformation, also traditionally referred to as a cavernous hemangioma (despite it not being a tumor) or cavernomas, are non-neoplastic slow flow venous malformations found in many parts of the body.
Terminology
Despite the ubiquity of use of the traditional terms cavernoma, ...