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.
1,423 results found
Article
Abdominal cavity
The abdominal cavity is divided into two major compartments, the peritoneum and retroperitoneum, early in fetal development.
The parietal peritoneum is reflected over the peritoneal organs to form a series of supporting peritoneal ligaments, mesenteries and omenta. The peritoneal reflections ca...
Article
Inframesocolic space
The inframesocolic space is the peritoneal space below the root of the transverse mesocolon. The supramesocolic space lies above the transverse mesocolon's root.
It can be divided into two unequal spaces posteriorly by the mesentery of the small bowel as it runs from the duodenojejunal flexure ...
Article
Supramesocolic space
The supramesocolic space is the peritoneal space above the root of the transverse mesocolon. The inframesocolic space lies below the root of the transverse mesocolon.
It can be arbitrarily divided into right and left supramesocolic spaces and subspaces. These are normally in communication with ...
Article
Transverse colon
The transverse colon is the longest and most mobile part of the large intestine. It measures up to 45 cm in length.
Gross anatomy
The transverse colon is the continuation of the ascending colon from the right colic flexure. It passes from the right to left hypochondrium in a downward convex p...
Article
Transverse mesocolon
The transverse mesocolon is a broad, meso-fold of peritoneum, which connects the transverse colon to the posterior wall of the abdomen.
It is continuous with the two posterior layers of the greater omentum, which, after separating to surround the transverse colon, join behind it, and are contin...
Article
Mesentery
A mesentery is a double layer of peritoneum that encloses the intestines and attaches them to the posterior abdominal wall 3. The term was originally only used to refer to the double layer of peritoneum that suspends the jejunum and ileum, but its meaning has been widened.
Mesenteries include:
...
Article
Peritoneum
The peritoneum (rare plural: peritonea or peritoneums) is a large complex serous membrane that forms a closed sac, the peritoneal cavity, within the abdominal cavity. It is a potential space between the parietal peritoneum lining the abdominal wall and the visceral peritoneum enveloping the abdo...
Article
Schatzki ring
A Schatzki ring, also called a Schatzki-Gary ring, is a symptomatic, narrow esophageal B-ring occurring in the distal esophagus and usually associated with a hiatus hernia.
Epidemiology
Relatively common, lower esophageal rings are found in ~6-14% of oesophagrams 9.
Associations
More than ...
Article
Gastro-esophageal reflux disease
Gastro-esophageal reflux disease (GERD), often shortened to reflux disease, is a spectrum of disease that occurs when gastric acid refluxes from the stomach into the lower end of the esophagus across the lower esophageal sphincter.
Epidemiology
It affects 10% to 20% of the adult population in ...
Article
Gastro-esophageal junction
The gastro-esophageal junction (GEJ) (also known as the esophagogastric junction) is the part of the gastrointestinal tract where the esophagus and stomach are joined.
Gross anatomy
The GEJ is normally mostly intra-abdominal and is 3-4 cm in length. To some extent, the esophagus slides in and ...
Article
Stomach
The stomach is a muscular organ that lies between the esophagus and duodenum in the upper abdomen. It lies on the left side of the abdominal cavity caudal to the diaphragm at the level of T10.
Gross anatomy
The stomach ("normal" empty volume 45 mL) is divided into distinct regions:
cardia: th...
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 retrocecal appendix. Overall they are seen in 10...
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
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
Marginal artery of Drummond
The marginal artery of Drummond, also known as the marginal artery of the colon, is a continuous arterial circle or arcade along the inner border of the colon formed by the anastomoses of the terminal branches of the superior mesenteric artery (SMA) and inferior mesenteric artery (IMA).
Gross a...
Article
Superior mesenteric artery
The superior mesenteric artery (SMA) is one of the three non-paired major splanchnic arteries in the abdominal cavity arising from the abdominal aorta and supplying the midgut; i.e. from mid duodenum to distal transverse colon.
Gross anatomy
Origin
Single vessel arising anteriorly from the ab...
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
Splenic artery
The splenic artery is one of the three branches of the celiac trunk, which supplies the spleen as well as large parts of the stomach and pancreas.
Gross anatomy
Origin and course
The splenic artery is one of the terminal branches of the celiac trunk, passing left from the celiac axis across t...
Article
Left gastric artery
The left gastric artery (LGA) is the smallest and first branch of the celiac artery.
Gross anatomy
The left gastric artery passes superiorly over the left crus of the diaphragm, approaching the esophageal opening of the diaphragm, giving off an esophageal branch to the distal esophagus, then...
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
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
Sclerosing mesenteritis
Sclerosing mesenteritis, also referred to as mesenteric panniculitis or retractile mesenteritis, is an uncommon idiopathic disorder characterized by chronic non-specific inflammation involving the adipose tissue of the bowel mesentery. It is often considered in the spectrum of autoimmune diseas...
Article
Retroperitoneal liposarcoma
Retroperitoneal liposarcoma is a subtype of liposarcoma and is a malignant tumor of mesenchymal origin that may arise in any fat-containing region of the body. It is one of the most common primary retroperitoneal neoplasms.
Epidemiology
Most cases occur in patients in the 5th to 7th decades of...
Article
Shwachman-Diamond syndrome
Shwachman-Diamond syndrome (SDS) or Shwachman-Bodian-Diamond syndrome (SBDS) is a rare autosomal recessive disorder characterized by 1 :
exocrine pancreatic insufficiency
metaphyseal chondrodysplasia
bone marrow hypoplasia (cyclic neutropenia)
Epidemiology
Shwachman-Diamond syndrome is a ra...
Article
Hydatid disease
Hydatid cysts result from infection by the Echinococcus tapeworm species and can result in cyst formation anywhere in the body.
Epidemiology
Cystic echinococcosis has a worldwide geographical distribution. The Mediterranean basin is an important endemic area 6,7.
Pathology
There are two main...
Article
Rigler sign (bowel)
The Rigler sign, also known as the double-wall sign, is a sign of pneumoperitoneum seen on an abdominal radiograph when gas is outlining both sides of the bowel wall, i.e. gas within the bowel's lumen and gas within the peritoneal cavity. It is seen with large amounts of pneumoperitoneum (>1000 ...
Article
Lower gastrointestinal bleeding (differential)
Lower gastrointestinal bleeding usually occurs distal to the ligament of Treitz, and has a wide differential diagnosis:
diverticular disease
enterocolitis
infective
Crohn’s disease
ulcerative colitis
ischemic colitis
vascular malformation
vascular ectasia
angiodysplasia
arteriovenous m...
Article
Upper gastrointestinal bleeding (differential)
An upper gastrointestinal bleed usually refers to bleeding proximal to the ligament of Treitz.
Pathology
Aetiolology
peptic ulcer
gastritis
esophagitis
duodenitis
Mallory-Weiss tear
varices
tumor
vascular abnormality
vascular ectasia
angiodysplasia
Dieulafoy lesion
vascular malform...
Article
Upper gastrointestinal bleeding
Upper gastrointestinal bleeding (UGIB) is defined as bleeding proximal to the ligament of Treitz.
Epidemiology
The incidence of acute upper GI bleeding is ~100 per 100,000 adults per year. Upper GI bleeding is twice as common in men as in women and increases in prevalence with age 5. The demog...
Article
Target sign (intussusception)
The target sign of intestinal intussusception, also known as the doughnut sign or bull's eye sign.
The appearance is generated by concentric alternating echogenic and hypoechoic bands. The echogenic bands are formed by mucosa and muscularis whereas the submucosa is responsible fo the hypoechoi...
Article
Fibromuscular dysplasia
Fibromuscular dysplasia (FMD) is a heterogeneous group of vascular lesions characterized by an idiopathic, non-inflammatory, and non-atherosclerotic angiopathy of small and medium-sized arteries.
Epidemiology
The prevalence is unknown 7. It is most common in young women with a female to male r...
Article
Zenker diverticulum
Zenker diverticulum, also known as a pharyngeal pouch, is a posterior outpouching of the hypopharynx, just proximal to the upper esophageal sphincter through a weakness in the muscle layer called the Killian dehiscence.
Epidemiology
More than 50% of the affected patients present in 60-80 years...
Article
Typhlitis
Typhlitis, also known as neutropenic colitis, is a necrotizing inflammatory condition which typically originates in the cecum and, often extends into the ascending colon, appendix or terminal ileum, by the time of presentation. In general patients are immunocompromised, usually neutropenic.
Ter...
Article
Turcot syndrome
Turcot syndrome is a polyposis syndrome. It is characterized by multiple colonic polyps and an increased risk of colon cancer and primary brain cancers.
Epidemiology
Turcot syndrome is a rare disease. Patients typically present in the second decade 3.
Pathology
Turcot syndrome is characteriz...
Article
Target sign (pyloric stenosis)
The target sign of pyloric stenosis is a sign seen due to hypertrophied hypoechoic muscle surrounding echogenic mucosa, seen in pyloric stenosis. This is likened to a target.
See also
antral nipple sign (pyloric stenosis)
cervix sign (pyloric stenosis)
shoulder sign (pyloric stenosis)
Article
String sign (disambiguation)
The string sign may refer to:
angiographic string sign
gastrointestinal string sign
string sign of parosteal osteosarcoma
myositis ossificans string sign
Article
String of pearls sign (gastrointestinal)
The string of pearls (or beads) sign can be seen on upright or decubitus abdominal radiographs as well as on CT in patients with small bowel obstruction, increased intraluminal fluid, and slow resorption of intraluminal gas.
It consists of an obliquely or horizontally oriented row of small gas ...
Article
String of pearls sign (disambiguation)
String of pearls sign can refer to:
string of pearls sign on an abdominal radiograph of fluid-filled dilated small bowel loops
string of pearls sign on cerebral MRI in deep border zone infarction
string of pearls sign on ultrasound in polycystic ovarian syndrome
string of pearls sign for ang...
Article
AAST spleen injury scale
The American Association for the Surgery of Trauma (AAST) splenic injury scale, most recently revised in 2018, is currently the most widely used grading system for splenic trauma.
The 2018 update incorporates "vascular injury" (i.e. pseudoaneurysm, arteriovenous fistula) into the imaging criter...
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
Small bowel fold thickening (differential)
The differential diagnosis of small bowel fold thickening is broad. Diffuse fold thickening may be "regular and smooth" or "irregular and nodular".
Regular, smooth generalized thickening
edema
congestive cardiac failure (CCF)
hypoalbuminemia
lymphatic obstruction
angioneurotic edema
infec...
Article
Small bowel
The small bowel (or small intestine) is the section of bowel between the stomach and the colon. It has distinctive mucosal folds, valvulae conniventes, and is made up of three functional units:
duodenum
jejunum
ileum
Terminology
Although anatomically it is stated that the duodenum forms the...
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
Sentinel loop
A sentinel loop is a short segment of adynamic ileus close to an intra-abdominal inflammatory process. When seen, it is usually identified on abdominal radiography.
The sentinel loop sign may aid in localizing the source of inflammation. For example, a sentinel loop in the upper abdomen may ind...
Article
Pyloric stenosis
Hypertrophic pyloric stenosis (HPS) refers to the idiopathic thickening of gastric pyloric musculature which then results in progressive gastric outlet obstruction.
Epidemiology
Pyloric stenosis is relatively common, with an incidence of approximately 2-5 per 1000 births, and a male predilect...
Article
Pseudovein sign (bowel)
The pseudovein sign can occur with active gastrointestinal bleeding where contrast extravasation during angiography may have a curvilinear appearance as it pools in the gastric rugae or mucosal folds of bowel, mimicking the appearance of a vein. However, contrast in the “pseudovein” persists bey...
Article
Portal venous gas
Portal venous gas is the accumulation of gas in the portal vein and its branches. It needs to be distinguished from pneumobilia, although this is usually not too problematic when associated findings are taken into account along with the pattern of gas (i.e. peripheral in portal venous gas, centr...
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...
Article
Portosystemic collateral pathways
Portosystemic collateral pathways (also called varices) develop spontaneously via dilatation of pre-existing anastomoses between the portal and systemic venous systems. This facilitates shunting of blood away from the liver into the systemic venous system in portal hypertension, as a means for r...
Article
Polyglandular autoimmune syndromes
Polyglandular autoimmune syndromes (PAS) are a rare set of diseases characterized by the presence of ≥2 autoimmune endocrine disease.
Pathology
Three types of PAS have been described.
PAS type I
a.k.a. APECED (autoimmune polyendocrinopathy, candidiasis and ectodermal dystrophy) or MEDAC (mu...
Article
Polyposis syndromes
The polyposis syndromes are disorders in which more than 100 gastrointestinal polyps are present throughout the GI tract:
hereditary
hereditary nonpolyposis colorectal cancer
familial adenomatous polyposis syndrome (FAPS)
classic FAP
Gardner syndrome
Turcot syndrome
Bannayan–Riley–Ruvalc...
Article
Peritoneal calcification
Peritoneal calcification is seen in a limited number of conditions that result in calcification of peritoneal structures. Therefore, the differential diagnosis is small:
psammoma bodies in malignancy (most frequently cystadenocarcinoma of the ovary): fine sand-like calcification
pseudomyxoma p...
Article
Paraganglioma
Paragangliomas, sometimes called glomus tumors, are rare neuroendocrine tumors arising from paraganglia.
Terminology
Paraganglia are clusters of neuroendocrine cells dispersed throughout the body and closely related to the autonomic nervous system, with either parasympathetic or sympathetic f...
Article
Pancreatoblastoma
Pancreatoblastomas are rare pediatric tumors of the pancreas. However, they are the most common pancreatic neoplasm of childhood and are often associated with a raised alpha-fetoprotein.
Epidemiology
There is slight male predilection. Usually occurs in the first decade of life with a mean age ...
Article
Pancreatic ducts
The exocrine pancreas is drained into the gastrointestinal tract via the main and accessory pancreatic duct. There are several anatomical variations of the typical ductal drainage pattern, reflecting variations in the embryological development and fusion of the dorsal and ventral pancreatic buds...
Article
Pancreatic neoplasms
There are numerous primary pancreatic neoplasms, in part due to the mixed endocrine and exocrine components.
Classification
Classification based on function
exocrine: ~99% of all primary pancreatic neoplasms
pancreatic ductal adenocarcinoma (commonly known as pancreatic cancer) 90-95%
acin...
Article
Omphalocele
Omphaloceles, also known as exomphalos (rare plural: exomphali), are congenital midline abdominal wall defects at the base of the umbilical cord insertion, with herniation of gut (or occasionally other structures) out of the fetal abdomen.
Epidemiology
The estimated occurrence can be up to 1:4...
Article
Omental cake
Omental cake refers to infiltration of the omental fat by material of soft-tissue density. The appearances refer to the contiguous omental mass simulating the top of a cake. Masses on the peritoneal surfaces and malignant ascites may also be present.
Pathology
The most common cause is metasta...
Article
Esophageal carcinoma
Esophageal carcinoma is relatively uncommon. It tends to present with increasing dysphagia, initially to solids and progressing to liquids as the tumor increases in size, obstructing the lumen of the esophagus.
Epidemiology
Esophageal cancer is responsible for <1% of all cancers and 4-10% of a...
Article
Esophageal and esophagogastric junction squamous cell carcinoma (staging)
Esophageal and esophagogastric junction squamous cell carcinoma staging refers to TNM staging of squamous cell carcinoma originating in the esophagus or esophagogastric junction (including tumors whose center is within the proximal 2 cm of the gastric cardia).
Related histologies included in th...
Article
Esophageal stricture
Esophageal stricture refers to any persistent intrinsic narrowing of the esophagus.
Terminology
The term peptic stricture refers specifically to those benign esophageal strictures caused by chronic acid reflux, although some - incorrectly - use it more loosely to refer to any benign esophagea...
Article
Esophageal web
Esophageal webs refer to an esophageal constriction caused by a thin mucosal membrane projecting into the lumen.
Epidemiology
Esophageal webs tend to affect middle-aged females.
Clinical presentation
Patients are usually asymptomatic and the finding may be incidental and unimportant. However...
Article
Nodular filling defects of duodenum (differential)
Nodular filling defects due to mucosal lesions in the duodenum are due to a number of processes. For a differential list which includes non-mucosal lesions see duodenal filling defects.
The differential diagnosis for mucosal lesions includes:
heterotopic gastric mucosa
1-2 mm
clustered
onl...
Article
Mycotic aneurysm
Mycotic aneurysms are aneurysms arising from infection of the arterial wall, usually bacterial. It is a complication of the hematogenous spread of bacterial infection, classically from the heart.
Epidemiology
Mycotic aneurysms are thought to represent only a minority of (0.65-2.6%) of all aor...
Article
Midgut volvulus
Midgut volvulus is a complication of bowel malrotation usually seen in neonates and infants. Presentation is usually with proximal small bowel obstruction and bilious vomiting. Without prompt treatment, there is a real and significant risk of small bowel ischemia, significant associated morbidit...
Article
Mercedes-Benz sign (gallbladder)
In the gallbladder, the Mercedes-Benz sign describes a star-shaped pattern of gas-fissuring within gallstones initially described on an abdominal radiograph 2.
Fissures, usually fluid-filled, are present in close to 50% of gallstones. Less than half of these fissured gallstones contain some amo...
Article
Meconium peritonitis
Meconium peritonitis refers to a sterile chemical peritonitis due to intra-uterine bowel perforation and spillage of fetal meconium into the fetal peritoneal cavity. It is a common cause of peritoneal calcification.
Epidemiology
The estimated prevalence is at ~1 in 35,000.
Pathology
The eti...
Article
Intestinal malrotation
Intestinal malrotation is a congenital anatomical anomaly that results from an abnormal rotation of the gut as it returns to the abdominal cavity during embryogenesis.
Although some individuals live their entire life with a malrotated bowel without associated symptoms, the abnormality does pred...
Article
Multiple endocrine neoplasia type 1
Multiple endocrine neoplasia type 1 (MEN1), also known as Wermer syndrome, is an autosomal dominant genetic disease that results in proliferative lesions in multiple endocrine organs, particularly the pituitary gland, pancreas, and parathyroid glands.
There are other multiple endocrine neoplas...
Article
Hereditary non-polyposis colorectal cancer
Hereditary non-polyposis colorectal cancer (HNPCC), also known as Lynch syndrome, is an autosomal dominant condition which predisposes to a host of malignancies, including colorectal cancer. It is considered the most frequent form of hereditary colorectal cancer. Diagnosis requires evaluation us...
Article
Liposarcoma
Liposarcomas are malignant tumors of fatty tissue and are the malignant counterpart to a benign lipoma. They are the second most common soft tissue sarcoma, after undifferentiated pleomorphic sarcoma.
Epidemiology
Liposarcomas are typically found in adults, typically between the ages of 40 and...
Article
Langerhans cell histiocytosis
Langerhans cell histiocytosis (LCH) is a rare multisystem disease with a wide and heterogeneous clinical spectrum and variable extent of involvement.
Terminology
Langerhans cell histiocytosis was previously known as histiocytosis X. The newer term is preferred as it is more descriptive of its...
Article
Large intestine
The large intestine (also known as the large bowel) is a 1.5 meter muscular tube that extends from the cecum to the rectum. It has three outer longitudinal muscular layers called taenia coli, which are about 30 cm shorter than the length of the large bowel causing characteristic sacculations int...
Article
Intussusception
Intussusception occurs when one segment of the bowel is pulled into itself or a neighboring loop of the bowel by peristalsis. It is an important cause of an acute abdomen in children and merits timely ultrasound examination and reduction to preclude significant sequelae, including bowel necrosis...
Article
Ischemic colitis
Ischemic colitis refers to inflammation of the colon secondary to vascular insufficiency and ischemia. It is sometimes considered under the same spectrum as intestinal ischemia. The severity and consequences of the disease are highly variable.
Epidemiology
Ischemic bowel is typically a disease...
Article
Intraductal papillary mucinous neoplasm
Intraductal papillary mucinous neoplasms or tumors (IPMNs or IMPTs) are epithelial pancreatic cystic tumors of mucin-producing cells that arise from the pancreatic ducts. They are most commonly seen in elderly patients.
On imaging, particularly MRCP, they are characterized by single or multipl...
Article
Gastrointestinal tract lipomas
Gastrointestinal tract lipomas are not uncommon and can be found anywhere along the entire length of the gastrointestinal tract.
For a more specific discussion, please refer to the articles on:
esophageal lipoma
gastric lipoma
Epidemiology
Gastrointestinal tract lipomas are most frequentl...
Article
Mesenteric ischemia
Mesenteric ischemia, also commonly referred to as bowel or intestinal ischemia, refers to vascular compromise of the bowel and its mesentery that in the acute setting has a very high mortality if not treated expediently. Mesenteric ischemia is far more commonly acute than chronic in etiology. Th...
Article
Indirect inguinal hernia
Indirect inguinal hernias (alternative plural: herniae), a type of groin herniation, are the most common type of abdominal hernia.
Epidemiology
It is five times more common than a direct inguinal hernia, and is seven times more frequent in males, due to the persistence of the processus vaginal...
Article
Incisional hernia
Incisional hernias (alternative plural: herniae) are relatively common and along with parastomal hernias, umbilical hernias, paraumbilical hernias, and Spigelian hernias, they are usually anterior abdominal hernias.
Epidemiology
Incisional hernias usually develop within a few months of surgery...
Article
Hirschsprung disease
Hirschsprung disease is the most common cause of neonatal colonic obstruction (15-20%). It is commonly characterized by a short segment of colonic aganglionosis affecting term neonates, especially boys.
Epidemiology
Hirschsprung disease affects approximately 1:5000-8000 live births. In short ...
Article
Hinchey classification of acute diverticulitis
The Hinchey classification for acute diverticulitis (anywhere along the bowel, not just the colon) has been variously adapted and modified since its original description, and is useful not only in academia but also in outlining successive stages of severity 3,5,6. Adoption and utility of the va...
Article
Hiatus hernia
Hiatus hernias (alternative plural: herniae) occur when there is herniation of abdominal contents through the esophageal hiatus of the diaphragm into the thoracic cavity.
Epidemiology
The prevalence of hiatus hernia increases with age, with a slight female predilection.
Clinical presentation
...
Article
Hereditary hemorrhagic telangiectasia
Hereditary hemorrhagic telangiectasia (HHT), also known as Osler-Weber-Rendu syndrome, is a rare inherited disorder characterized by abnormal blood vessel formation in the skin, mucous membranes, and organs including the lungs, liver, and central nervous system.
Epidemiology
Worldwide prevalen...
Article
Sandwich sign (mesentery)
A sandwich sign, sometimes known as a hamburger sign, refers to a mesenteric nodal mass, either para-aortic or not, giving an appearance of a hamburger. Confluent lymphadenopathy on both sides of the mesenteric vessels gives rise to an appearance described as the sandwich sign 2.
The sign is sp...
Article
String sign (bowel)
The gastrointestinal string sign (also known as the string sign of Kantor) refers to the string-like appearance of a contrast-filled bowel loop caused by its severe narrowing.
Originally used to describe the reversible narrowing caused by spasms in Crohn disease, it is now used for any severe n...
Article
Gastric lymphoma
Gastric lymphoma may either represent secondary involvement by systemic disease or primary malignancy confined to the stomach.
Epidemiology
Gastric lymphoma represents the most common site of extranodal lymphoma, accounting for 25% of all such lymphomas, 50% of all gastrointestinal lymphomas...
Article
Gardner syndrome
Gardner syndrome is one of the polyposis syndromes. It is characterized by:
familial adenopolyposis
multiple osteomas: especially of the mandible, skull, and long bones
epidermal cysts
fibromatoses
desmoid tumors of mesentery and anterior abdominal wall
Other abnormalities include:
supern...
Article
Gallstone ileus
Gallstone ileus is an uncommon cause of 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.
Epidemiology
Although ...
Article
Feline esophagus
Feline esophagus also known as esophageal shiver, refers to the transient transverse bands seen in the mid and lower esophagus on a double-contrast barium swallow.
Pathology
The appearance is almost always associated with active gastro-esophageal reflux 2,3 and is thought to be due to contract...
Article
Fat halo sign (inflammatory bowel disease)
The fat halo sign (in colonic imaging) refers to a feature seen on CT abdominal scans, and represents infiltration of the submucosa with fat, between the muscularis propria and the mucosa. It is characterized by an inner (mucosa) and outer (muscularis propria and serosa) ring of enhancing bowel ...
Article
Epiploic appendagitis
Epiploic appendagitis is a rare self-limiting ischemic/inflammatory process that affects the appendices epiploicae of the colon and may either be primary or secondary to adjacent pathology. This article pertains to primary (spontaneous) epiploic appendagitis. The term, along with omental infarct...