The splenic artery is one of three branches coeliac trunk and supplies the spleen as well as large parts of the stomach and pancreas.
Origin and course
The splenic artery is one of the terminal branches of the coeliac trunk, passing from the coeliac axis toward the splenic hilum...
Splenic artery pseudoaneurysms are a rare type of pseudoaneurysm arising from any portion of the splenic artery and its branches.
Unlike splenic artery true aneurysms, splenic artery pseudoaneurysms will nearly always present with symptoms 2. Fewer than 200 cases of sple...
Splenic calcifications can occur is various shapes and forms and can occur from a myriad of aetiological factors.
The usual calcification observed in radiographs are the multiple, miliary form presenting numerous small rounded densities averaging from three to five millimeters in diameter where...
Splenic cysts, although not particularly common, are the most common focal lesion of the spleen. They may be congenital or secondary.
The incidence is ~0.75 per 100,000.
Usually asymptomatic and incidentally discovered at imaging. Left upper quadrant pain and t...
Splenic epidermoid cysts are a type of non-parasitic primary splenic cyst.
They are thought to account for 10-25% of benign non-parasitic cysts of the spleen 3. There may be an increased female predilection.
The clinical presentation can vary ranging from b...
Splenic haemangiomas (also known as splenic venous malformations) while being rare lesions, are considered the second commonest focal lesion involving the spleen after simple splenic cysts 5,12.
Most splenic venous malformations are so called cavernous malformations, which are found throughout ...
Splenic haemangiomatosis is a situation there are multiple, diffuse splenic haemangiomas replacing its entire parenchyma. It is a very rare entity .
It can occur as a manifestation of systemic angiomatosis or, less commonly, confined to the spleen (diffuse isolated splenic haemangiom...
Splenic hamartomas are very rare and usually solitary although may be present as multiple nodules present in tuberous sclerosis or Wiskott-Aldrich syndrome.
The only recently described entity sclerosing angiomatoid nodular transformation (SANT) of the spleen, a non-neoplastic vascular entity de...
Splenic infarction is a result of ischaemia to the spleen, and in many cases requires no treatment. However, identification of the cause of infarction is essential.
Splenic infarcts can occur due to a number processes, involving either arterial supply, the spleen itself and the ...
There are a number of splenic lesions and anomalies:
Benign mass lesions
splenic cysts: see cystic lesions of the spleen
splenic haemangioma: commonest benig...
Splenic lymphangiomas are relatively rare benign tumours that correspond to malformations of the lymphatic system.
Most occur in children, were rarely reported in adults2.
Presentation ranges from asymptomatic incidental finding to a large multicentric, ...
Atraumatic or spontaneous splenic rupture is rare, especially when compared to traumatic splenic rupture.
The pathogenesis of atraumatic splenic rupture is not well understood. Splenomegaly is present in almost all patients (~95%), although rupture of normal spleens (both in size an...
Splenic siderotic nodules, also known as Gamna-Gandy bodies, of the spleen, are most commonly encountered in portal hypertension. The pathophysiological process is the result of microhaemorrhage resulting in haemosiderin and calcium deposition followed by fibroblastic reaction.
Splenic trauma can occur after blunt or penetrating trauma or secondary to medical intervention (i.e. iatrogenic). The spleen is the most frequently injured organ after blunt trauma.
Patients may present with left upper quadrant/left chest pain, left shoulder tip pain (re...
The splenic vein drains the spleen, part of the pancreas, and part of the stomach.
Origin and course
The splenic vein is formed by splenic tributaries emerging at the splenic hilum in the splenorenal ligament at the tip of the tail of pancreas. It runs in the splenorenal ligame...
Splenomegaly is a term which refers to enlargement of the spleen. The normal adult splenic length upper limit is usually around 12-15 cm. Also one should know how to calculate splenic index, volume and mass by CT and MR techniques. Massive splenomegaly is a term used when the spleen weighs >1000...
Splenorenal ligament is a peritoneal ligament. It represents the dorsal most part of dorsal mesentery.
It contains pancratic tail.
In settings of portal hypertension, collateral circulation may establish within the splenorenal ligament.
Splenosis is one type of ectopic splenic tissue (the other being accessory spleen). It is an acquired condition and is defined as autoimplantation one or more focal deposits of splenic tissue in various compartments of the body.
Abdominal splenosis is seen after abdominal trauma or surgery (e.g...
Sprue is the collective term for the malabsorptive gastrointestinal enteropathies although it may be used to refer directly to tropical sprue. It is composed of two entities:
non-tropical sprue / coeliac disease
In each, the radiologic features are not sensitive enough to confi...
Stepladder sign may refer to:
intra-capsular breast implant rupture (ultrasound)
air-fluid levels in obstructed small bowel (erect abdominal radiograph)
Stepladder sign represents the appearance of air-fluid distended small bowel loops that appear to be stacked on top of each other, typically observed on erect abdominal radiographs in the setting of small bowel obstruction.
On breast imaging, the stepladder sign is used to describe intracapsul...
Stercoral perforation is defined as a bowel perforation due to pressure necrosis from a faecal mass (faecaloma) 1. It is uncommon, but a life-threatening, complication of unresolved faecal impaction and can be a cause of acute abdomen secondary to faecal peritonitis.
It may repres...
The Stierlin sign refers to repeated emptying of the caecum, seen radiographically as barium remaining in the terminal part of the ileum and in the transverse colon. This occurs due to irritation of the caecum caused by M. tuberculosis.
The stomach lies between the oesophagus and duodenum in the upper abdomen. It lies on the left side of the abdominal cavity caudal to the diaphragm.
The stomach (normal volume 45 mL) is divided into distinct regions:
cardia: the area that receives the oesophagus (gastro-oesophog...
Stomal ulcers may occur after surgery for peptic ulcer disease, and are more common in settings of a retained gastric antrum or an incomplete vagotomy (occurrences which are not common with modern surgical technique). There is also a higher risk with Zollinger-Ellison syndrome.
Streak ovaries are a form of ovarian dysgenesis and are associated with Turner syndrome. Occasionally they may be functional and secondary sexual characteristics may develop.
Streak ovaries are seen when there is abnormality or absence of the X chromosome.
The string of beads sign is the description typically given to the appearance of the renal artery in fibromuscular dysplasia (FMD) but may also be used to describe the appearance of splanchnic arteries in segmental arterial mediolysis (SAM). It refers to the appearance arising from the stenoses ...
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 ultrasound in polycystic ovarian syndrome
string of pearls sign for angiographic appearances in fibromuscular dysplasia
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 ...
The gastrointestinal string sign (also known as string sign of Kantour) refers to the string-like appearance of a contrast-filled bowel loop caused by severe narrowing of a bowel loop.
Originally used to describe the reversible narrowing caused by spasms in Crohn disease, it is now used for any...
The string sign may refer to:
angiographic string sign
gastrointestinal string sign
string sign of parosteal osteosarcoma
Stump appendicitis refers to inflammation of the residual appendiceal tissue post appendectomy.
Partial removal of appendix with a residual stump, allows for a chance of recurrent appendicitis. Chances of a partial removal is found to be higher in cases where there is a wrong identification of ...
Subcapsular splenic haematomas are a type of splenic haematoma that occurs beneath the splenic capsule.
They can occur in both traumatic and non-traumatic situations.
abdominal: splenic trauma 3, a subcapsular haematoma is part of imaging criteria for grades I-III of t...
Subdiaphragmatic free gas is one of the ways of detecting presence of free intraperitoneal air (i.e. pneumoperitoneum). It is the presence of free, extraluminal air in the anterior subhepatic space.
Subdiaphragmatic free gas is well appreciated as the a...
The Sudeck point (or Sudeck critical point) refers to a specific location in the arterial supply of the rectosigmoid junction, namely the origin of the last sigmoid arterial branch from the inferior mesenteric artery (IMA) 1.
This arterial branch usually forms an anstomosis with a branch of th...
The superior mesenteric artery (SMA) is one of the three non-paired arteries that provide blood to the midgut and other abdominal viscera.
Single vessel arising anteriorly from the abdominal aorta at the level of L1.
Courses anteroinferiorly, behind the neck of p...
There are two distinct vascular compression disorders due to compression of another structure by the superior mesenteric artery. The terminology is sometimes confusing and they can occur in association.
superior mesenteric artery syndrome (Wilkie syndrome): compression of the third part of th...
Superior mesenteric artery (SMA) syndrome, also known as Wilkie syndrome, is a rare acquired vascular compression disorder in which acute angulation of superior mesenteric artery (SMA) results in compression of the third part of the duodenum leading to obstruction.
It should not be confused wit...
The superior mesenteric vein (SMV) accompanies the superior mesenteric artery (SMA) and drains the midgut to the portal venous system.
Origin and course
Mesenteric venous arcades, which accompany the arteries, unite to form the jejunal and ileal veins in the small bowel mesenter...
origin: the terminal branch of the inferior mesenteric artery is the superior rectal artery
course: descends into the pelvic cavity in the sigmoid mesocolon, crossing the left common iliac vessels
branches: opposite the S3 vertebra the superior rectal artery divides into two terminal ...
The supramesocolic space is the intraperitoneal 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 spaces and subspaces. These are normally in communication with each other...
The supravesical fossae are concave depressions of peritoneum in the paravesical space bounded by the median umbilical fold and the medial umbilical folds. It partially overlies the inguinal (Hesselbach’s) triangle. The supravesical fossae are usually occupied by small bowel loops and the urinar...
Surgical haemostatic material is used to control bleeding intraoperatively and is hence frequently voluntarily left in the operative bed, not to be confused with a gossypiboma which is foreign material left by mistake. It can mimic an abscess on imaging studies. Various types are available, the ...
Syphilis is the result of infection with the gram negative spirochete Treponema pallidum, subspecies pallidum. It results in a heterogeneous spectrum of disease with many systems that can potentially be involved, which are discussed separately.
Despite the discovery of penicillin...
Systemic lupus erythematosus (SLE) is a complex autoimmune disease with multisystem involvement. It is also sometimes classified as a vasculitis.
There is an overall increased female predilection. In adults, women are affected 9-13 times more than males. In children, this ratio i...
The taeniae coli are the three outer muscular bands of the colon. They sit on top of the inner circumferential layer and result in the classical appearance of the colon: the haustral markings are interrupted unlike the valvulae conniventes within the small bowel.
Tailgut duplication cysts, also known as retrorectal cystic hamartomas, are rare congenital lesions that are thought to arise from vestiges of the embryonic hindgut.
There is a recognised strong female predilection. While it can present at any age presentation is usually at aroun...
The Tanaka criteria (or Fukuoka consensus guidelines) is a classification system for intraductal papillary mucinous neoplasms (IPMNs) and mucinous cystic neoplasms (MCNs).
The original international consensus guidelines (2006) were referred to as the Sendai criteria. This later evolved into th...
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 hypoechogenic bands. The echogenic bands are formed by mucosa and muscularis whereas the submucosa is responsible fo the hypoec...
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 that of a target.
antral nipple sign
cervix sign of pyloric stenosis
shoulder sign of pyloric stenosis
Tc-99m pertechnetate is one of the technetium radiopharmaceuticals used in imaging of thyroid, colon, bladder and stomach.
photon energy: 140 keV
biological half-life: 6 hours
normal distribution: stomach, thyroid, salivary glands, (testicles)
Technetium-99m sulfur colloid is one of the technetium radiopharmaceuticals.
photon energy: 140 keV
physical half-life: 6 hours
bone marrow: 5%
target organ: liver, spleen
Tear drop sign of the superior mesenteric vein (SMV) is one of the important signs in the staging of pancreatic adenocarcinoma. Its importance lies in its diagnosis as well as prognostic significance. This sign is used in assessing the resectability of pancreatic cancer.
Tension gastrothorax describes a rare life-threatening condition caused by mediastinal shift due to a distended stomach herniating into the thorax through a diaphragmatic defect.
Presentation is generally with acute and severe respiratory failure, with clinical features ...
Tension pneumoperitoneum is a special and rare type of pneumoperitoneum, in which the free intra-abdominal peritoneal gas is under pressure. The mechanism is thought to be a ball-valve effect allowing the one-way accumulation of gas. This results in:
elevation and splinting of the diaphragm red...
The differential diagnosis for a terminal ileitis is quite extensive, and includes:
inflammatory bowel disease
Crohn's disease (most common)
backwash ileitis due to ulcerative colitis
The terminal ileum is the most distal segment of small bowel. It immediately precedes the small bowel's connection with the colon through the ileocaecal valve. It is of particular interest since a number of infectious and inflammatory processes preferentially involve the segment.
location: the ...
Thumbprinting is a radiographic sign of large bowel wall thickening, usually caused by oedema, related to an infective or inflammatory process (colitis). The normal haustra become thickened at regular intervals appearing like thumbprints projecting into the aerated lumen.
Tissue tropism is a phenomenon by which certain host tissues preferentially support the growth and proliferation of pathogens. This concept is central to the radiological evaluation of infectious disease.
As infections that display tissue tropism will thrive in certain tissue locati...
Toxic megacolon (TM) is complication that can be seen in both types of inflammatory bowel disease, and less commonly in infectious colitis, as well as in some other types of colitis.
The mechanisms involved in development of toxic megacolon are not entirely clear, although chemical m...
Toxoplasmosis is a common worldwide parasitic disease caused by the protozoan Toxoplasma gondii. It is usually an asymptomatic infection, but it is related with several sequelae when acquired in-utero or related with cerebral abscesses due to its reactivation in immunocompromised patients (e.g. ...
Tracheo-oesophageal fistula is a pathological communication between the trachea and oesophagus.
It can be broadly classified into two types:
congenital tracheo-oesophageal fistula
acquired tracheo-oesophageal fistula: from malignancy/tuberculosis
Transient (non-obstructing) intussusception without a lead point is known to occur in both adults and children and occurs more frequently than was previously reported.
Transient intussusception of the small bowel has been reported in adults with coeliac disease and Crohn disease but is most fre...
The transpyloric plane, also known as Addison's plane, is an imaginary axial plane located midway between the jugular notch and superior border of pubic symphysis, at approximately the level of L1 vertebral body. It an important landmark as many key structures are visualised at this level, altho...
The transverse colon is the longest and most mobile part of the large intestine. It measures up to 45 cm in length.
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...
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...
Traumatic abdominal wall hernia (TAWH) represents traumatic disruption of musculature and fascia of anterior abdominal wall without skin penetration.
Traumatic abdominal wall hernia (TAWH) is caused by blunt trauma to the abdomen.
In adults, it usually results from road traffic acci...
The triple bubble sign is the classic radiographic appearance observed in jejunal atresia 1,2. The appearance is due to a proximal obstruction caused by the atretric jejunum. It is equivalent to the double bubble sign, but a third bubble is seen because of proximal jejunal distention.
Troisier sign is the clinical finding of a hard and enlarged left supraclavicular node (Virchow node), and is considered a sign of metastatic abdominal malignancy.
It is sometimes referred to as Virchow node, which is the name given by Dr Rudolf Virchow (1821-1902), a German pathol...
Tropical pancreatitis is a subtype of chronic pancreatitis associated with malnutrition, tropical countries, and a young age of onset. There are characteristic, large ductal calculi, which may measure up to a few centimeters in size. This is in contrast to the small, speckled calculi more common...
Tuberculous peritonitis is a result of peritoneal involvement in tuberculosis. It is frequently seen in association with other forms of gastrointestinal tuberculosis 6.
Tuberculosis is usually confined to the respiratory system but may involve any organ system, particularly in imm...
The small intestine is rarely the site of malignant tumours, although it accounts for ~75% of the entire length of the GI tract and more than 90% of the mucosal surface. Approximately 40 different histologic tumour types have been described.
In this article, an overview will be given of the mo...
A tumour-to-tumour metastasis, also known as a collision tumour, is a rare metastatic process in which a primary malignant tumour ('donor') metastasises to another tumour ('recipient'), most commonly a benign tumour such as a meningioma.
Tumour-to-tumour metastasis is considered v...
Turcot syndrome is one of the variations in polyposis syndromes.
Patients typically present in the second decade 3.
Turcot syndrome is characterised by:
CNS tumours: most commonly glioblastoma or medulloblastoma
It is thought to carry...
Typhlitis, also called caecitis or neutropaenic colitis, is a necrotising inflammatory condition which typically involves the caecum and, sometimes, can extend into the ascending colon or terminal ileum.
Typhlitis was first described in children with leukaemia and severe neutropae...
Ulcerative colitis is an inflammatory bowel disease that not only predominantly affects the colon, but also has extraintestinal manifestations.
Typically ulcerative colitis manifests in young adults (15-40 years of age) and is more prevalent in males but the onset of disease after...
Ultrasound guided biopsy is one form of image guided biopsy, typically performed by a radiologist. It is the most common form of image guided biopsy, offering convenience and real time dynamic observation with echogenic markers on cannulae allowing for precise placement.
It can potentially be ...
Ultrasound guided percutaneous drainage is one form of image guided procedure, allowing minimally invasive treatment of collections that are accessible by ultrasound study.
It has several advantages and disadvantages over CT, which include:
is a dynamic study, allowing greater prec...
Umbilical hernias are the most common ventral hernia and occur in the midline.
Ten times more common in females 2 and represent ~5% of all abdominal hernias 4.
Umbilical hernias present in the midline as painless or painful mass.
Upper gastrointestinal bleeding (UGIB) is defined as bleeding proximal to the ligament of Treitz.
The incidence of acute UGIB is ~100 per 100,000 adults per year. UGIB is twice as common in men as in women and increases in prevalence with age 5. The demographics of the affected in...
Ultrasound abdomen is one of the tests that is commonly used in the assessment of patients with abdominal pain. It is particularly useful for the assessment of solid organs and fluid-filled structures.
This is a summary article; we do not have a more in-depth reference articl...
The valvulae conniventes, also known as Kerckring folds, plicae circulares or just small bowel folds, are the mucosal folds of the small intestine, starting from the second part of the duodenum, they are large and thick at the jejunum and considerably decrease in size distally in the ileum to di...
Vascular Ehlers-Danlos syndrome (EDS) or type IV Ehlers-Danlos syndrome (EDS 4) is the most malignant form of Ehlers-Danlos syndrome. This form is often accompanied by neurovascular complications secondary to vessel dissections and/or aneurysms.
Vascular EDS represents about 4% of...
Vertical-banded gastroplasty (VBG) is an older, purely restrictive procedure used to treat morbid obesity.
It involves creating a small gastric pouch, based on the lesser curvature of the stomach (which is thicker and less resistant to stretching than the greater curvature), by using...
Vicarious contrast material excretion (VCME) defines excretion of water-soluble contrast material in a way other than via normal renal secretion.
The most common vicarious excretion of water-soluble contrast material is via the liver, resulting in increased bile density seen in the gallbladder...
VIPomas are a very rare pancreatic endocrine tumour that classically presents with watery diarrhoea and hypokalaemia. These tumours secrete, and get their name from, vasoactive intestinal peptide (VIP).
VIPomas represent <2% of pancreatic endocrine tumours 2.
Vitamin B3 (niacin or nicotinic acid) is a water soluble vitamin that is an important part of the coenzyme nicotinamide adenine dinucleotide (NAD+) which is involved in many reactions of cellular metabolism.
Pathological manifestation occur in niacin deficiency known as pella...
Von Hippel-Lindau (vHL) disease is characterised by the development of numerous benign and malignant tumours in different organs (at least 40 types 1) due to mutations in the VHL tumour suppressor gene on chromosome 3.
The disease is rare with an estimated prevalence of 1:35,000-5...
Walled-off pancreatic necrosis (WOPN) is a late complication of acute pancreatitis, although it can occur in chronic pancreatitis or as a result of pancreatic trauma. Differentiation of WOPN from pancreatic pseudocyst is essential because management differs. WOPN may need aggressive treatment to...
Wandering spleen is a rare condition in which the spleen migrates from its usual anatomical position, commonly to the lower abdomen or pelvis.
Wandering spleen is rare, with a reported incidence of <0.5%.
Diagnosis is most commonly made between ages 20 and 40 and is more common i...
The water siphon test may be performed as part of a barium swallow to assess for gastro-oesophageal reflux in a hiatal hernia. It is performed in the supine RPO position with the patient drinking water continuously. The test is said to be positive if there is visible barium reflux in the oesopha...
Whipple disease is a rare infectious multisystem disorder caused by the actinobacteria Tropheryma whipplei.
The incidence of Whipple disease is not truly known, one Swiss study estimated it at approximately 1 per 1.5 million per year 7.
The peak age for presentation is in the fif...
Gastrointestinal manifestations are a key component of Whipple disease. The gastrointestinal manifestations of t. whipplei are also known as intestinal lipodystrophy.
Extensive infiltration of lamina propria with large macrophages infected by intracellular Tropheryma whipplei causes...