Fucosidosis is a rare inherited autosomal recessive lysosomal storage disorder, hypomyelinating disorder, and mucopolysaccharidosis-like disorder, characterized by multiorgan accumulation of fucose-containing products.
It is considered very rare, with approximately only 100 cases ...
Fukuoka consensus guidelines, also referred to as the Tanaka criteria, is a classification system for intraductal papillary mucinous neoplasms (IPMNs) and mucinous cystic neoplasms (MCNs).
The prior international consensus guidelines (2006) were referred to as the Sendai criteria, which later ...
The functional gastrointestinal disorders (FGIDs) are a set of conditions characterized by their chronic GI manifestations, in the absence of structural abnormality of the gut. These conditions are common and may be disabling in nature. The understanding of their pathogenesis is incomplete, comp...
Fundic gland polyps (FGP) are the most common type of gastric polyp.
FGPs occur most commonly in middle-aged females. They have been reported to be identified in ~1% of gastroscopies 3,4.
FGPs are usually an asymptomatic, incidental finding 1.
Fundoplications are forms of antireflux surgery used as a second line of treatment of gastroesophageal reflux disease after failure of medical treatment and the first line of treatment of paraesophageal hernia.
A gastric fold is wrapped around the distal esophagus which enforces the ...
Agenesis of the gallbladder describes the rare congenital absence of the gallbladder.
overall incidence is estimated <0.1% (range 0.04-0.1%)
reported 3:1 female predominance of symptomatic cases
equivalent gender distribution in autopsy cases
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...
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...
Gardner syndrome is one of the polyposis syndromes. It is characterized by:
multiple osteomas: especially of the mandible, skull, and long bones
desmoid tumors of mesentery and anterior abdominal wall
Other abnormalities include:
A gasless abdomen refers to a paucity of gas on abdominal radiography, and the specific cause can usually be identified when the patient's history is known. Common causes include:
small bowel obstruction
Gastric adenocarcinoma, commonly, although erroneously, referred to as gastric cancer, refers to a primary malignancy arising from the gastric epithelium. It is the most common gastric malignancy. It is the third most common GI malignancy following colon and pancreatic carcinoma.
Gastric antral vascular ectasia (GAVE), also known as watermelon stomach, is a rare condition affecting the stomach. It is one of the diagnoses to consider in older patients with severe anemia and occult or profuse gastrointestinal bleeding (especially in those with cardiac, liver, or renal dise...
Gastric antral webs are a ring of mucosa in the distal stomach (gastric antrum) that can lead to gastric outlet obstruction. A circumferential ring of mucosa has also been termed a "gastric antral diaphragm".
Gastric antral webs are rare. There is an association with trisomy 21 an...
A gastric band is a popular form of bariatric surgery and is a surgically placed device, used to assist in weight loss and is adjustable.
Performed laparoscopically, a silicone band device is placed around the stomach to reduce its volume. The band is adjustable via a port placed in ...
Gastric band malposition is an early complication from laparoscopic gastric band procedures which are performed for obesity. It can occur as in isolation or with other gastric band complications.
As surgical experience of lap gastric banding has accumulated, it has become a relatively rare comp...
Gastric band slippage is a late complication of laparoscopic gastric banding surgery performed for obesity. It is reported to occur in 4-13% of cases 1-3.
It can occur in either an anterior or posterior direction.
Patients can present with cessation of weight loss, sever...
Gastric band erosion or penetration is a potentially serious complication following laparoscopic gastric band surgery for obesity.
Gastric band erosion is a delayed complication observed in between 0.3-14% of patients 1,2.
Patients often present non-specif...
The gastric bubble is a radiolucent rounded area generally nestled under the left hemidiaphragm representing gas in the fundus of the stomach.
On a lateral radiograph, the gastric bubble is usually located between the abdominal wall and spine. It can be seen on chest or abdominal plain films. I...
This is a basic article for medical students and other non-radiologists
Gastric cancer, also known as stomach cancer or gastric carcinoma, refers to a cancer that arises from the mucosal lining of the stomach. It is the commonest gastric malignancy.
This is a summary article...
Gastric cancer staging is routinely performed using the TNM staging system. This article is based on the 7th edition of the TNM classification of malignant tumors.
TNM staging (7th edition)
T1a: tumor invades the lamina propria and or muscularis mucosae
T1b: tumor invades submucosa
Gastric diverticula are sac-like projections that usually originate from the gastric fundus, most commonly on the posterior surface. They are the least common of the gastrointestinal diverticula.
Gastric diverticula are rare and commonly detected incidentally. The incidence varie...
Gastric duplication cysts are rare congenital foregut duplication cysts affecting the stomach. Gastrointestinal tract duplication cysts (GTDCs) most commonly affect the ileum, followed by the esophagus, large bowel, and jejunum; gastric location accounts for less than 10% of all gastrointestinal...
Gastric emphysema, referring to the presence of gas in the wall of the stomach, is a relatively rare imaging finding 1. The stomach is the least common location for intramural gas in the gastrointestinal tract.
There is a wide range of causes, ranging from life-threatening...
Gastric leiomyomas are rare benign mesenchymal tumors, usually asymptomatic and found incidentally.
Most leiomyomas are found incidentally in asymptomatic patients. Symptoms related to a gastric leiomyoma will depend on the tumor size, location, and presence/absence of u...
Gastric lipomas are a location-specific subtype of gastrointestinal lipomas and represent a rare benign mesenchymal tumors of the stomach. They can be definitively diagnosed on CT.
Gastric lipomas are rare, accounting for <5% of gastrointestinal lipomas and <1% of all gastric neo...
The gastric lymph node stations were originally divided into 16 groups, as proposed by the Japanese Research Society for Gastric Cancer in 1963.
The stomach regions and their drainage into regional lymph nodes:
cardia and proximal lesser curvature drain into left gastric lymph n...
Gastric lymphoma may either represent secondary involvement by systemic disease or primary malignancy confined to the stomach.
Gastric lymphoma represents the most common site of extranodal lymphoma, accounting for 25% of all such lymphomas, 50% of all gastrointestinal lymphomas...
Gastric metastases are rare, found in less than 2% of patients who die of a carcinoma 6.
Usually affects the middle-aged and elderly population. Affects males and females equally without predilection.
The patient may be asymptomatic, but the most common sig...
Gastric outlet obstruction is a syndrome resulting from mechanical obstruction of stomach emptying.
Gastric outlet obstruction can be due to malignant or benign causes.
adenocarcinoma (second most common 4)
lymphoma (less common than other malignancies as...
Gastric polyps are uncommon findings, even on endoscopy where they are encountered in only 2-6% of patients.
There are a number of gastric polyp subtypes 1-3:
virtually no malignant potential
typically small (<1 cm), multiple, and sessil...
Gastric (peptic) ulcers can be detected on multiple imaging modalities, but are best evaluated on a double-contrast barium upper GI study. This article discusses their appearance on a double contrast study, for a more complete description, see the full article on peptic ulcers.
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...
Gastric volvulus is a specific type of volvulus that occurs when the stomach twists on its mesentery. It should be at least 180° and cause bowel obstruction to be called gastric volvulus. Merely gastric rotation on its root is not considered gastric volvulus.
Gastric wall fatty infiltration refers to an appearance seen on CT of the abdomen whereby the wall of the stomach is thickened due to infiltration of fat into the submucosa.
Although it can be seen in the context of Crohn disease it is more commonly seen in the asymptomatic general population. ...
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 gastrinoma triangle, also known as Passaro's triangle, is an anatomical area in the abdomen, from where the majority (90%) of gastrinomas are thought to arise.
The triangle is formed by joining the following three points:
superiorly: confluence of the cystic and...
Gastritis refers any form of mucosal inflammation of the stomach and can sometimes be part of a wider gastroenteritis. It may have acute of chronic forms.
While may not may...
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 posterior wall of the first part of the duodenum, the gastroduodenal artery is one of t...
Gastrointestinal amyloidosis is relatively common, although symptomatic involvement is more rare. It is diagnosed if there are persistent gastrointestinal (GI) symptoms with endoscopic biopsy proven amyloid deposition.
Tends to affect middle-aged and older patients.
Gastrointestinal angiodysplasias or angioectasias are one of the most common causes of occult gastrointestinal bleeding.
Peak incidence occurs in patients in their 60-70s 3.
Patients can present with symptoms and signs upper or lower gastrointestinal bleedi...
Cytomegalovirus (CMV) infection of the gastrointestinal tract is usually seen in patients who are severely immunocompromised, such as solid organ transplantation and is common in HIV/AIDS, and is, in fact, the most common gastrointestinal manifestation of AIDS 1,2.
Gastrointestinal leiomyomas are smooth muscle tumors without malignant potential that may develop in any part of the gastrointestinal system:
Small bowel leiomyoma
Gastrointestinal MRI contrast agents are varied and can be either positive or negative agents. Acceptance of the use of MRI in abdominal imaging has been limited in part by difficulty in distinguishing bowel from intra-abdominal masses and normal organs. The use of enteric contrast agents can ai...
Gastrointestinal neuroendocrine tumors (GI NETs) can be functional or non-functional:
functional NETs can be challenging to localize as:
they are often small in size at the time of diagnosis
arise in many sites throughout the body
non-functioning and/or malignant NETs often are larger at p...
Gastrointestinal nodular lymphoid hyperplasia is a type of nodular lymphoid hyperplasia that can be found elsewhere in the body. It is formed out of gut-associated lymphoid tissue (GALT), and most often is a diagnostic dilemma for radiologists in the stomach and terminal ileum.
Gastrointestinal schwannomas are extremely rare mesenchymal neoplasms which arise in relation to the gastrointestinal tract.
They are reported to typically present at about the 3rd to 5th decades of life 4.
Patients are often asymptomatic but may occasional...
Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract. They account for ~5% of all sarcomas, and are mostly found within stomach and mid-distal small bowel. They respond remarkably well to chemotherapy.
Previously these tumors ...
The gastrointestinal tract (GI tract) includes any part of the oral cavity, oropharynx, hypopharynx, esophagus, stomach, small bowel, colon, rectum and anal canal.
The non-qualified term bowel , a.k.a. intestines or gut, is used to refer to the combination of the small bowel and l...
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:
Gastrointestinal tract lipomas are most frequentl...
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.
The GEJ is normally mostly intra-abdominal and is 3-4 cm in length. To some extent, the esophagus slides in and ...
Gastro-esophageal reflux disease (GERD) 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 (LES).
It affects 10% to 20% of the adult population in the United States and Western ...
This is a basic article for medical students and other non-radiologists
Gastric-esophageal reflux disease (GERD) is a spectrum of disease that occurs when gastric acid refluxes into the lower esophagus
This is a summary article; read more in our article on gastro-esophageal ...
A gastro-pleural fistula is a very rare situation characterized by a pathological communication between the stomach and the pleural cavity.
They can occur in number of situations:
trauma (stab injuries 3)
iatrogenic (following bariatric, pulmonary or esophageal surgery 1)
Gastroptosis is characterized by abnormal downward displacement of the stomach. It may be part of a wider spectrum called visceroptosis.
There is paucity of literature about the actual prevalence of the condition. It is more common in females.
It has nonspe...
Gastroschisis refers to an extra-abdominal herniation (evisceration) of fetal or neonatal bowel loops (and occasionally portions of the stomach and or liver) into the amniotic cavity through a para-umbilical anterior abdominal wall defect.
The estimated incidence is at around 1-...
The gastrosplenic ligament is a peritoneal ligament which is formed by ventral part of the dorsal mesentery.
The gastrosplenic ligament extends from the greater curvature of the stomach to the hilum of the spleen.
the short gastric arteries.
the left gastroepiploi...
Gaucher disease (GD) is the most common lysosomal storage disorder in humans. It is an autosomal recessive, multisystem disease arising from a deficiency of glucocerebrosidase or beta-glucosidase activity, resulting in the accumulation of a glycolipid (glucocerebroside) within the lysosomes of m...
A mnemonic to remember the causes of generalized colitis is:
I: infectious colitis e.g. E. coli, cytomegalovirus
I: inflammatory, e.g. pseudomembranous colitis, Crohn disease, ulcerative colitis
I: ischemic colitis
N: neoplastic, e.g. lymphoma
R: radiation colitis
To facilitate clinical description, the general topography of the abdomen is divided into four quadrants or nine regions by lines on the surface of the anterior abdominal wall. The four quadrants are created by vertical and horizontal lines passing through the umbilicus, whereas the nine regions...
Geophagy is the intentional ingestion of earth, soil or clay and is a form of pica. This practice is not uncommon in the southern regions of the United States or provinces of Africa. It is found most commonly in children and pregnant women 3,4. Although geophagy may be seen in the context of a v...
Giant colonic diverticula, also referred to as giant colonic pseudodiverticula, are an uncommon form of presentation of colonic diverticulosis and are characterized by large diverticular masses, usually filled with stool and gas, that communicate with the colonic lumen.
Globus pharyngeus is the subjective feeling of a lump in the throat which can have a variety of causes, it is not a diagnosis in its own right. In modern practice globus is often evaluated by flexible nasoendoscopy in the first instance since many patients present to otorhinolaryngology services...
Glucagon is a polypeptide hormone central to the regulation of glucose homeostasis, acting as an antagonist to insulin. In imaging it is used as an antiperistaltic agent in GI studies, although its clinical efficacy is controversial.
Glucagon is a 29-amino acid polypeptide hormone t...
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.
Accounts for 1% of all the neuroendocrine tumors a...
Gluten-related disorders are a collection of conditions that are the result of a reaction to the consumption of gluten a protein found in wheat, barley and rye 1.
Gluten-related disorders can be broadly divided into 1,2:
celiac disease: most common and most widely recognized
Glycogenic acanthosis is a benign finding on esophagography in elderly patients.
It most commonly occurs in patients >40 years of age and incidence and numbers of lesions increase by age. No gender predilection exists. Typically patients are asymptomatic.
It occurs fr...
Glycogen storage disease type I (GSD-I), also known as von Gierke disease, is a type of glycogen storage disease where there is excess deposition of glycogen primarily in the liver, but also in the kidney and small bowel.
It occurs approximately one in every 100,000 live births 2,...
A gossypiboma, also called textiloma or cottonoid, refers to a foreign object, such as a mass of cotton matrix or a sponge, that is left behind in a body cavity during surgery. It is an uncommon surgical complication. The manifestations and complications of gossypibomas are so variable that diag...
Graft versus host disease (GvHD) is a frequent complication of allogeneic hematopoietic stem cell transplantation, commonly known as bone marrow transplantation. Anti-rejection drugs have reduced the incidence, although it does still frequently occur.
Graft versus host disease can p...
Granular mucosal pattern of the esophagus represents very fine nodularity of the esophageal mucosal surface. This finding is non-specific and may represent:
reflux esophagitis (most common)
superficial spreading esophageal carcinom...
The great vessel space is the fourth retroperitoneal space along with the anterior and posterior pararenal spaces, and the perirenal space 1,2. Unlike other retroperitoneal spaces, it is not well-defined by fascial planes and thus disease processes affecting other retroperitoneal spaces can also...
The Grey Turner sign refers to the clinical finding of atraumatic flank ecchymosis, which is occasionally associated with retroperitoneal hemorrhage, classically due to hemorrhagic pancreatitis 2. It is thought to occur when blood extravasates from the posterior pararenal space and crosses throu...
The Griffiths point, also known as Griffiths critical point, refers to the site of watershed anastomosis between the ascending left colic artery and the marginal artery of Drummond occurring in the region of the splenic flexure. Most anatomy texts describe the location as two-thirds along the tr...
Groin hernias (herniae also used) may be congenital or acquired, and represent a large proportion of all abdominal wall hernias.
The subtypes based on location are:
direct inguinal hernia
indirect inguinal hernia: five times commoner than direct
Gullo syndrome, also known as benign pancreatic hyperenzymemia, 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. It is a diagnosis of exclusion made when all other laboratory assays an...
A gastrointestinal fistula is an abnormal connection between the gut and another epithelial / endothealial - lined surface, such as another organ system, the skin surface, or elsewhere along the gastrointestinal tract. Some authors exclude fistulas involving the large bowel and esophagus when cl...
The gut signature sign is an ultrasound term used to describe the appearance of the gastrointestinal wall.
The bowel wall has five layers, composed of alternating hyperechoic and hypoechoic appearances. Anatomically these layers are as follows (innermost to o...
Hemangiopericytomas of the spleen are very rare vascular neoplasm with only a few case reports available at the time of writing.
Splenic hemangiopericytomas are typically asymptomatic or can result in splenomegaly.
These are soft tissue vascular neoplasms aris...
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
Pancreatic manifestations of hemochromatosis typically occur with primary hemochromatosis, as the organ is usually spared in the secondary form of the disease.
For a general discussion, and for links to other system specific manifestations, please refer to the article on hemochromatosis.
Hemoperitoneum (plural: haemoperitoneums) is the presence of blood within the peritoneal cavity.
penetrating or non-penetrating abdominal trauma (often with associated organ injury) 1
ruptured ectopic pregnancy
ovarian cyst rupture
aneurysm or pseudoaneurysm rupture
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...
Haemosuccus pancreaticus, also known as pseudohaemobilia or haemoductal pancreatitis, is defined as upper gastrointestinal tract hemorrhage originating from the pancreatic duct into the duodenum via the ampulla of Vater, or major pancreatic papilla.
male:female ratio is 7:1
The Haggitt level is a histopathological term used for describing the degree of infiltration from a malignant polypoidal lesion.
Levels of invasion
0: carcinoma in situ or intramucosal carcinoma
1: invasion of the submucosa, but limited to the head of the polyp
2: invasion extending into the...
The Hampton line is a thin millimetric radiolucent line seen at the neck of a gastric ulcer in barium studies (profile view), indicating its benign nature. It is caused by a thin line of mucosa overhanging the ulcer's crater.
History and etymology
It was originally described by Aubrey Otis Ham...
The H and M lines are reference lines for the pelvic floor on imaging studies and help detect and grade pelvic floor prolapse on defecography studies.
The H line is drawn from the inferior margin of the pubic symphysis to the posterior aspect of the anorectal junction, and represents the diamet...
Hartmann pouches are a technique in colon surgery. After a segment of colon is resected, there are generally two options with regards to what to do with the two ends of the colon:
both the upstream end of the colon (the end of the colon through which fecal contents would pass) and the downstr...
Hartmann procedure (HP) (or proctosigmoidectomy) is an operation in which the sigmoid colon is resected and the distal colon brought out as a colostomy in the left iliac fossa. The remnant rectum stump is sewn shut. It is a quick and straightforward intervention and currently finds most favor in...
The haustral folds (Latin: haustrum, plural: haustra) represent folds of mucosa within the colon. The haustra refer to the small segmented pouches of bowel separated by the haustral folds. They are formed by circumferential contraction of the inner muscular layer of the colon.
The outer longitu...
Haustral markings are the radiological appearance of the haustral folds within the colon. Disappearance of the haustral folds results in the lead pipe appearance of ulcerative colitis.
Hellmer sign is a radiographic finding depicting medial displacement of the lateral edge of the liver from the peritoneal wall. It was originally described as a pathognomonic sign of ascites. However, this displacement can also be caused by intraperitoneal fat, extraperitoneal free fluid or a ma...
Hematemesis is the vomiting of blood, it is an indication of upper gastrointestinal bleeding. Mortality is generally near to 10% 1,2,4. Please see the main article on upper gastrointestinal bleeding for more detail.
Treatment and prognosis
In patients with moderate to severe hematemesis, life...