The duodenojejunal (DJ) flexure or junction is the anatomical border between the duodenum and the jejunum.
The DJ flexure is located anterolateral to the aorta at the level of the upper border of the second lumbar vertebra. It makes a sharp turn anteroinferiorly to become the jej...
The duodenum is the first part of the small intestine and is the continuation of the stomach.
The duodenum is a 20-30 cm C-shaped hollow viscus predominantly on the right hand side of the vertebral column. It lies at the level of L1-3 and the convexity of the duodenum usually enc...
Duplex appendix is a rare anomaly of the appendix and is usually discovered incidentally during surgery for appendicitis.
Duplication of the vermiform appendix is extremely rare. It is found in only 1 in 25,000 patients (incidence ~0.004%) operated on for acute appendicitis. Altho...
Dysphagia refers to subjective awareness of difficulty or obstruction during swallowing. It is a relatively common and increasingly prevalent clinical problem.
Fluoroscopy is the mainstay of imaging assessment but manometry can help evaluate the esophageal motor pattern and lower esophageal sp...
Dysphagia megalatriensis, also known as cardiovascular dysphagia or cardiac dysphagia, is an impairment of swallowing due to oesophageal compression from a dilated left atrium.
Presentation is generally with mild dysphagia, although a minority of patients will have dysph...
Ebola virus disease (EVD) (also known as Ebola haemorrhagic fever (EHF) or simply Ebola) is a viral haemorrhagic disease caused by the Ebola Filovirus. Ebola is an extremely virulent virus with case fatality rates of approximately 70% 1.
First recognized in 1967 after polio vaccin...
Ectopic pancreatic tissue (or heterotopic pancreatic tissue) refers to the situation where rests of pancreatic tissue lie outside and separate to the pancreatic gland. Most patients are completely asymptomatic.
It is reportedly relatively common, affecting ~5% (range 1-10%) 1 of p...
Ehlers-Danlos syndrome comprises a heterogeneous group of collagen disorders (hereditary connective tissue disease).
There is a recognised male predominance.
Clinically manifests by skin hyperelasticity and fragility, joint hypermobility and blood vessel fr...
Emphysematous gastritis is a cause of gastric emphysema, and specifically refers to infectious gastritis. It is an uncommon entity with a high mortality rate. In this condition, microorganisms (e.g. Escherichia coli, Clostridium perfringens) produce the gas, which is identified within the stomac...
Emphysematous pancreatitis is an unusual complication of acute pancreatitis caused by necrotising infection of the pancreas. It is associated with gas-forming bacteria and characterized by the presence of gas within or around the pancreas.
Infection with gas-forming bacteria such as...
Endocrine tumours of the pancreas arise from the pancreatic islet cells and include some distinct tumours that match the cell type of origin.
Pancreatic endocrine tumours have commonly been referred to as "islet cell tumours", referring to the islets of Langerhans, from which they...
Endoscopic retrograde cholangiopancreatography (ERCP) is a diagnostic and interventional procedure technique using both endoscopy and fluoroscopy for examination and intervention of the biliary tree and pancreatic ducts. It is typically performed by doctors with endoscopic qualifications (e.g. g...
Endoscopic ultrasound (EUS) is a procedure combining the range of endoscopy with the diagnostic abilities of ultrasound. EUS is used in the imaging of the upper GI tract and surrounding structures as well as the respiratory tract (where it is referred to as endobronchial ultrasound, EBUS). A hi...
Enteritis refers to inflammation of the small bowel. When associated with inflammation of the stomach, the term gastroenteritis is used which is usually caused by infection.
inflammatory bowel disease
Enteroclysis is a gastrointestinal technique designed to provide improved evaluation of the small bowel. The conventional fluoroscopic technique is not widely used since it is somewhat invasive, time and labour intensive, and not particularly pleasant for the patient. The exam also requires a de...
An entero-cutaenous fistula is one between a loop of bowel and the skin. The content of the bowel being released into the skin surface, such as the anterior abdominal wall.
An entero-enteric fistula is one formed between two parts of the small bowel.
The can result for a number of reasons most commonly with inflammatory bowel disease, in particular Crohn.
Enterovirus 71 is one of the viruses that causes hand-foot-and-mouth disease in children. It is an enterovirus, one of the picornaviruses.
Infection with enterovirus 71 predominantly results in a vesicular rash of the hands and feet that follows a prodrome of symptoms including fever, vomiting ...
Eosinophilic gastroenteritis (EG) is an uncommon disease characterised by diffuse infiltration of any or all layers of gut wall by eosinophils.
EG is an uncommon but not rare disease with slight male predominance, it can affect any age group but usually patients present in their...
Epidermolysis bullosa refers to a rare group of genetically determined conditions characterised by blistering of the skin. This can be limited to the soles and palms or extensive whole body involvement.
limited to the mucosa of the gastr...
An epigastric hernia occurs ventrally through a defect in linea alba superior the umbilicus. It is also known as a fatty hernia of linea alba.
Shows a midline defect which is usually small with or without herniation of omenta...
Epiphrenic diverticula are pulsion diverticula of the distal oesophagus arising just above the lower oesophageal sphincter, more frequently on the right posterolateral wall.
They are less frequent than traction mid oesophageal diverticula, but may have more clinical relevance.
Epiploic appendages (or appendix epiploica, plural: appendices epiploicae) are peritoneum-lined protrusions of subserosal fat that arise from the surface of the large bowel.
Epiploic appendages typically measure 1.5 x 3.5 cm but have been reported to measure up to 15 cm in lengt...
Epiploic appendagitis is a rare self limiting inflammatory/ischaemic process involving an appendix epiploica 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 infarction is...
The epiploic foramen, also called the foramen of Winslow), is a passage between the greater (general peritoneal space) and lesser sac (omental bursa) allowing communication between these two spaces.
It has the following borders:
anterior: the free edge of the lesser ...
Erect chest x-rays are standard positioning but are also a specific examination performed for the assessment of subdiaphragmatic free gas (pneumoperitoneum).
This is a summary article; we do not have a more in-depth reference article.
Evacuation proctography (defecography) is a fluoroscopic technique to evaluate pelvic floor disorders. The technique traditionally involves fluoroscopy and barium, but an analogous MRI technique has also been developed (see: MR defaecating proctography).
incomplete defecation / con...
Extramural vascular invasion (EMVI) is the direct invasion of a blood vessel (usually a vein) by tumour. In rectal cancer, this can occur on a macroscopic level and be detected on staging MRI. It is a significant prognostic factor, being a predictor of haematogenous spread.
Extrapulmonary tuberculosis (TB) refers to the haematogenous spread of Mycobacterium tuberculosis.
Extrapulmonary tubercuosis can occur as a primary form of the disease, i.e. direct infection of an extrapulmonary organ without the presence of primary pulmonary tuberculosis or it can ...
A faecaloma is a mass of faeces most frequently noted in the rectum and sigmoid colon, that is much harder than a faecal impaction due to coprostasis.
Usually, the faecal matter accumulates in the intestine, then stagnates and increases in volume until the intestine becomes deformed ...
The falciform ligament is a broad and thin peritoneal ligament. It is sickle-shaped (Latin: "falciform") and a remnant of the ventral mesentery of the fetus.
It is situated in an anteroposterior plane but lies obliquely so that one surface faces forward and is in contact with the peritoneum beh...
The falciform ligament sign (also called the Silver sign) is a sign seen with a pneumoperitoneum.
It is almost never seen in isolation. If there is enough free gas to outline the falciform ligament, there is usually enough gas to also provide at least a Rigler sign.
The falciform ligament con...
Familial adenomatous polyposis syndrome (FAPS) is characterised by the presence of hundreds of adenomatous polyps in the colon. It is the most common of the polyposis syndromes.
Familial polyposis coli, attenuated familial adenomatous polyposis and Gardner syndrome are all variants...
The fascial tail sign is the linear extension along the fascia/muscular aponeurosis from a deeper tumour.
It appears as a tail and is best appreciated on MRI, classically seen in desmoid tumours as T2 hypointense bands that progressively enhance particularly on delayed ph...
The fat halo sign refers to a feature seen on CT examination of the abdomen, and represents infiltration of the submucosa with fat, between the muscularis propria and the mucosa. It is characterised by an inner (mucosa) and outer (muscularis propria and serosa) ring of enhancing bowel wall along...
The fat ring sign (also known as a fat halo sign) describes preservation of fat around the mesenteric vessels and around soft tissue nodules on a background of diffuse fat stranding in patients with mesenteric panniculitis or mesenteric lipomas.
This finding may help distinguish mesenteric pan...
Fat stranding is a common sign on CT seen anywhere fat can be found but is most commonly seen in the abdomen/pelvis, but also in the retroperitoneum, thorax and subcutaneous tissues. It can be helpful in localising both acute and chronic pathology.
Fat stranding can a...
Fat stranding is a sign that is seen on CT. It describes the change in attenuation of fat around an inflamed structure and is a very helpful signpost for intra-abdominal pathology.
This is a summary article; read more in our article on fat stranding on CT.
Feline oesophagus also known as oesophageal shiver, refers to the transient transverse bands seen in the mid and lower oesophagus on a double contrast barium swallow.
The appearance is almost always associated with active gastro-oesophageal reflux 2,3 and is thought to be due to contraction of ...
The femoral canal, or the medial compartment of the femoral sheath, is the inverted cone-shaped fascial space medial to the femoral vein within the upper femoral triangle. It is only 1-2 cm long and opens superiorly as the femoral ring. It serves two purposes:
allows the femoral vein to expand ...
Femoral hernias are a type of groin herniation and comprise of a protrusion of a peritoneal sac through the femoral ring into the femoral canal, posterior and inferior to the inguinal ligament. The sac may contain preperitoneal fat, omentum, small bowel, or other structures.
The femoral ring is the superior opening of the femoral canal. It boundaries are:
medial: lacunar ligament
anterior: medial part of the inguinal ligament
lateral: femoral vein within the intermediate compartment of the femoral sheath
posterior: pectineal ligament overlying the pectineus and ...
Fetal enteric duplication cysts are enteric duplication cysts presenting in utero.
They result from an abnormal recanalisation of the gastrointestinal tract. They comprise of a two-layer smooth muscle wall and an internal epithelium of a respiratory or intestinal type. These cysts ma...
Fibrosing colonopathy a condition characterised by progressive submucosal fibrosis, particularly of the proximal colon. It is associated with high dose lipase supplementation used to treat exocrine insufficiency of the pancreas, such as in treatment for cystic fibrosis.
It is more...
The Fleischner sign refers to a widely gaping, thickened, patulous ileocaecal valve and a narrowed, ulcerated terminal ileum associated with tuberculous involvement of the ileocaecum.
Fleischner sign (enlarged pulmonary artery)
The floating aorta sign refers to displacement of the abdominal aorta away from the vertebral column.
It is a radiographic/CT sign of retroperitoneal masses.
On lateral lumbar spine radiographs, the expected location of the posterior aortic wall is expected to be ≤10 mm ...
Flocculation refers to the breakdown of a barium suspension during a fluoroscopic study.
The small bowel environment eventually separates out a barium suspension, and this can occur during the normal course of a barium study (15 minutes to three hours). When the suspension flocculates, it no lo...
Fluoroscopic nasojejunal (NJT) or nasogastric tube (NGT) insertion is a valuable procedure offered by radiologists in patient care.
The majority of nasogastric tubes are inserted on the ward level and nasojejunal tubes may be placed in theatre at the time of surgery. In difficult cases, inserti...
Foamy oesophagus is an appearance seen on a single contrast barium study in Candida oesophagitis with associated scleroderma/achalasia (stasis).
Pathophysiologic basis of the foamy oesophagus is uncertain. Stasis is a predisposing factor. Foam is produced directly by the fungal organ...
Focussed Assessment with Sonography for Trauma (FAST) scan is a point-of-care ultrasound examination performed at the time of presentation of a trauma patient.
It is invariably performed by a clinician, who should be formally trained, and is considered as an 'extension' of the trauma clinical ...
The football sign is seen in cases of massive pneumoperitoneum, where the abdominal cavity is outlined by gas from a perforated viscus. The median umbilical ligament and falciform ligament are sometimes included in the description of this sign, as representing the sutures.
Which football is use...
The foramina of Morgagni, also known as the sternocostal triangles, are small defects in the posterior aspect of the anterior thoracic wall between the sternal and costal attachments of the diaphragm. The internal thoracic vessels descend through these foramina to become the superior epigastric ...
Foregut duplication cysts are type congenital duplication cyst. They are sometimes classified under broncho-pulmonary foregut malformations.
Entities that fall under forgut duplication cysts include:
other enteric cysts
oesophageal duplication cysts
Free intraperitoneal fluid may be termed free fluid or (less correctly) free intra-abdominal fluid. It may be seen in small volumes in female patients, particularly around the time of menses and in some healthy young men.
This is a summary article; we do not have a more in-de...
The Frey procedure is a type of pancreaticojejunostomy designed to treat chronic pancreatitis.
The fundamental technique is similar to the Puestow procedure, with a lateral incision of the pancreatic duct from an anterior approach, and then a side-to-side anastomosis between the pancreas and a ...
The Frimann-Dahl sign is a diagnostic sign demonstrated when three dense lines, representing the sigmoid walls, are seen converging to the site of obstruction in sigmoid volvulus and associated with empty rectal gas 1.
History and etymology
Johan Frimann-Dahl (1902-82) was a Norwegian Professo...
Frostberg inverted 3 sign is a radiological sign seen on a barium examination where there is effacement and distortion of the mucosal pattern on the medial wall of the second part of the duodenum due to focal mass and local oedema. It is most commonly associated with carcinoma of the head of the...
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 first line of treatment of paraesophageal hernia.
A gastric fold is wrapped around the distal esophagus which enforces the lowe...
Agenesis of the gallbladder is a rare congenital anomaly.
The incidence is <0.1% (range 0.04-0.1%). There is strong female predominance present among the symptomatic cases.
Most patients with agenesis of the gallbladder are asymptomatic. Although some patie...
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 (SBO). 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 ileocaecal valve.
Gallstone pancreatitis refers to pancreatitis caused by gallstones, specifically distal choledocholithiasis. Gallstones is 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 characterised by:
familial adenopolyposis (FAP)
multiple osteomas especially of the mandible, skull and long bones
desmoid tumours of mesentery and anterior abdominal wall
Other abnormalities include:
A specific cause of the gasless abdomen can usually be made when the patient's history is known. Common causes include:
small bowel obstruction
large abdominal mass - due to displacement
Gastric adenocarcinoma, commonly referred to as gastric cancer, refers to a primary malignancy arising from the gastric epithelium. It is the most common gastric malignancy.
Gastric cancer is rare before the age of 40, but its incidence steadily climbs after that and peaks in the...
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 anaemia and occult or profuse gastrointestinal bleeding (especially in those with cardiac, liver, or renal dis...
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 surgically placed device, used to assist in weight loss. It is now the most popular form of bariatric surgery, largely replacing gastric bypass procedures 1.
Performed laparoscopically, a silicone band device is placed around the stomach to reduce its volume. The band is adj...
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...
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; read more in our article on gastric cancer.
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 tumours.
TNM staging (7th edition)
T1a: tumour invades the lamina propria and or muscularis mucosae
T1b: tumour 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 gastrointestinal diverticulum.
Gastric diverticula are rare and commonly detected incidentally. The incidence varies from...
A gastric duplication cyst is a rare congenital foregut duplication cyst affecting the stomach. It accounts for less than 10% of all gastrointestinal duplications. The most common site of gastrointestinal tract duplication cysts (GTDC's) are the ileum, followed by oesophagus, large bowel and jej...
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-threateni...
Gastric lipomas are a location-specific subtype of gastrointestinal lipomas and represent a rare benign mesenchymal tumours 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 ne...
Gastric lymph node stations were originally divided into 16 groups proposed by the Japanese Research Society for Gastric Cancer in 1963.
The areas of stomach which drain into regional lymph nodes:
cardia and proximal lesser curvature drain into left gastric lymph nodes, then int...
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 commonly than other malignancies...
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 (<1cm), multiple, and sessile...
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 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.
Gastrinomas are the second most common pancreatic endocrine tumour 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 genera...
The gastrinoma 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 common bile ducts
The gastroduodenal artery is a terminal branch of the common hepatic artery which mainly supplies the pylorus, proximal duodenum, and the head of the pancreas. Due to its proximity to the anterior wall of the first part of the duodenum, the gastroduodenal artery is one of the most important sour...
Gastrointestinal amyloidosis is relatively common, although symptomatic involvement is more rare. It is diagnosed if there is 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.
Patients can present with symptoms and signs upper or lower gastrointestinal bleeding although they can commonly be an incidental finding.
Cytomegalovirus 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.
Approximately 30% of...
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 tumours (GI NETs) can be functional or non-functional:
functional NETs can be challenging to localise 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 ...
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.