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 labeled RBC is one of the technetium radiopharmaceuticals used in the assessment of GI bleeding.
photon energy: 140 KeV
physical half-life: 6 hours
normal distribution: heart, vessels, spleen
threshold for detection is 0.0...
Tc-99m pertechnetate (Na+ 99mTc O4-) is one of the technetium radiopharmaceuticals used in imaging of thyroid, colon, bladder and stomach.
Technetium (99mTc) has eight oxidation states 6, from -1 to +7; specifically, the oxidation state of technetium in the pertechnetate anion (99mTcO4-) is +7....
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
The teardrop sign of the superior mesenteric vein is one of the important signs in the local staging of pancreatic adenocarcinoma. Its importance lies in its diagnostic, as well as prognostic, significance. This sign is used in assessing the resectability of pancreatic cancer.
The telltale triangle sign, also known as the triangle sign or telltale triangle, is a radiographic sign seen on plain abdominal radiographs in a supine, cross table lateral or decubitus view that signifies presence of pneumoperitoneum, of any cause 1,2.
It describes the appearance of a radiolu...
Tenesmus (also known as rectal tenesmus to differentiate from vesical tenesmus) is stated by patients as the unpleasant symptom that there remains something to evacuate from the rectum despite passing a stool. It is often - but not always - painful. Frequently there are actually no feces left in...
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 d...
The differential diagnosis for a terminal ileitis is quite extensive, and includes:
inflammatory bowel disease
Crohn 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 ileocecal valve. It is of particular interest since a number of infectious and inflammatory processes preferentially involve the segment.
location: the m...
Thumbprinting is a radiographic sign of large bowel wall thickening, usually caused by edema, 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 is a 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.
Toxic colitis is preferred by many now as the colon is not always dilated.
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-esophageal fistula is a pathological communication between the trachea and esophagus.
It can be broadly classified into two types:
congenital tracheo-esophageal fistula
acquired tracheo-esophageal fistula: from malignancy/tuberculosis
Transanal endoscopic microsurgery is a technique for resection of some focal T1 stage rectal cancers.
Features of a rectal cancer that may make it a candidate for this approach
well- or moderately-differentiated tumors that are T1 N0 M0 (confined to submucosa without spread)
within 8 c...
Transhiatal esophagectomy is a type of esophagectomy, a surgery that removes the distal esophagus, usually for esophageal carcinoma.
Removal of the esophagus can be performed through the chest wall (a transthoracic esophagectomy), but the thoracotomy is a major component of patient pain and com...
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.
Most commonly, transient intussusception in adults is idiopathic, incidental, and of no clinical consequence 4. Uncommonly, tra...
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 visualized 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 describes traumatic disruption of musculature and fascia of anterior abdominal wall without skin penetration.
Abdominal skin ecchymosis or abrasions may be seen.
Traumatic abdominal wall hernia is caused by blunt trauma to the a...
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 the Virchow node, which is the name given by Rudolf Virchow (1821-1902) 6, a German pat...
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 tumors, 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 tumor types have been described.
In this article, an overview will be given of the most...
A tumor-to-tumor metastasis, also known as a collision tumor, is a rare metastatic process in which a primary malignant tumor ('donor') metastasizes to another tumor ('recipient'), most commonly a benign tumor such as a meningioma.
Tumor-to-tumor metastasis is considered very rare...
Turcot syndrome is one of the variations in polyposis syndromes. It is characterized by multiple colonic polyps and an increased risk of colon and primary brain cancers.
Turcot syndrome is a rare disease. Patients typically present in the second decade 3.
Twinkling artifact is the result of intrinsic machine noise seen with color Doppler ultrasound 1. It occurs as a focus of alternating colors on Doppler signal behind a reflective object (such as calculi), which gives the appearance of turbulent blood flow 2. It appears with or without an associa...
Typhlitis, also called cecitis or neutropenic colitis, is a necrotizing inflammatory condition which typically involves the cecum and, sometimes, can extend into the ascending colon or terminal ileum.
Typhlitis was first described in children with leukemia and severe neutropenia (...
Typhoid fever or just typhoid is an infectious disease caused by the Salmonella enterica serovar Typhi bacterium, usually spread by the orofecal route. The condition is characterized by severe fever, acute systemic symptoms, with occasionally serious enterocolic complications.
Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) 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 di...
Ultrasound elastography, also called as sono-elastography, is a modern evolutionary method of sonographic imaging. Techniques include shear wave elastography (also known as transient elastography) and strain elastography (also known as static or compression elastography). These techniques assess...
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 u...
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...
The umbilical folds are a series of 5 folds of parietal peritoneum on the deep surface of the anterior abdominal wall and consist of:
a single midline median umbilical fold,
bilateral medial umbilical folds, and
bilateral lateral umbilical folds
Umbilical hernias are the most common ventral hernia and occur in the midline through the umbilicus.
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.
The umbilicus is the fibrous remnant of the foetal attachment of the umbilical cord after birth. All layers of the anterior abdominal wall fuse at the umbilical ring, a small round defect in the linea alba located just inferior to the midpoint between the xiphoid process of the sternum and the p...
Upper gastrointestinal bleeding (UGIB) is defined as bleeding proximal to the ligament of Treitz.
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...
An upper gastrointestinal bleed usually refers to bleeding proximal to the ligament of Treitz.
Upper GI studies are a fluoroscopic evaluation of the esophagus, stomach, and duodenum.
There are a number of indications for an upper GI study, including:
upper abdominal pain with a possible gastric or duodenal origin
gastritis or duodenitis
gastric outlet obstruction
The urachus sign is a radiographic sign of pneumoperitoneum. It represents the outline of the median umbilical ligament with free abdominal gas in a supine patient, as seen on a plain abdominal radiograph.
This is a basic article for medical students and other non-radiologists
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.
Valentino syndrome, or Valentino appendix, refers to a clinical syndrome of right lower quadrant or right iliac fossa pain secondary to a perforated peptic ulcer. It is an important differential diagnosis for acute appendicitis.
Although thought to be a very rare manifestation of ...
The valvulae conniventes, also known as Kerckring folds/valves, 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 ileu...
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...
The veiled right kidney sign is a sonographic sign described in pneumoretroperitoneum, most commonly due to duodenal perforation.
It refers to the appearance of the right kidney on transabdominal ultrasound 1-4. On ultrasound, there is difficulty in obtaining images of the right kidney due to i...
Venous intravasation is the unintended introduction of radiographic contrast material into the local venous system. It is a well-recognized phenomenon during retrograde urethrograms 1,2 and hysterosalpingograms (HSG), although can occur with other invasive procedures in the vicinity of venous pl...
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...
A vestibule is an anatomical term and refers to a small cavity at the proximal end of a tube. It may refer to:
History and etymology
Vestibule derives ultimate...
Vicarious contrast material excretion (VCME) defines excretion of water-soluble contrast material in a way other than via normal renal excretion. The most common vicarious excretion of water-soluble contrast material is via the liver, resulting in increased bile density seen in the gallbladder. ...
Videofluoroscopic swallow studies (also often called modified barium swallow studies) are a variation on traditional barium swallow studies. Although typical barium swallow studies / esophagrams evaluate the pharynx, the goal in these studies is to even more closely evaluate the oral cavity, pha...
VIPomas are a very rare type of pancreatic endocrine tumors that secrete, and get their name from, vasoactive intestinal peptide (VIP). The clinical syndrome resulting from these tumors is commonly known as WDHA syndrome, as an acronym of the cardinal symptoms of watery diarrhea, hypokalemia, an...
Virgin abdomen is used to describe the abdomen of a patient who has never had any surgical procedure on their abdomen. It is usually used in the context of someone presenting with an acute small bowel obstruction and whether adhesions might be the underlying etiology.
The conventional wisdom be...
Vitamin B3 (niacin or nicotinic acid) is a water-soluble vitamin, part of the vitamin B complex, that is an important part of the coenzyme nicotinamide adenine dinucleotide (NAD+) which is involved in many reactions of cellular metabolism.
pellagra is the clinical syndrome of...
Von Hippel-Lindau (vHL) disease is characterized by the development of numerous benign and malignant tumors in different organs (at least 40 types 1) due to mutations in the VHL tumor suppressor gene on chromosome 3.
The disease is rare with an estimated prevalence of 1:35,000-50,...
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 years and is more co...
The water siphon test may be performed as part of a barium swallow to assess for gastro-esophageal reflux. 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 esophagus, and is more sens...
A clinical presentation of weight loss is extremely common and often a source of marked anxiety for the patient. The commonest cause of unintentional weight loss (UWI) is gastrointestinal tract disease, and not malignancy.
The published literature lacks a consistent definition of w...
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 Tropheryma whipplei are also known as intestinal lipodystrophy.
Extensive infiltration of the lamina propria with large macrophages infected by intracellular T. whipplei ca...
The Whipple procedure (or partial pancreaticoduodenectomy) is considered the definitive surgical operation to resect carcinoma of the head of the pancreas, periampullary carcinoma, or duodenal carcinoma 1.
In the procedure, the head of the pancreas and adjacent duodenum is resected. ...
Whipple triad is the clinical presentation of pancreatic insulinoma and consists of:
fasting hypoglycemia (<50 mg/dL)
symptoms of hypoglycemia
immediate relief of symptoms after the administration of IV glucose
History and etymology
The triad and also the Whipple procedure were both named a...
The whirlpool sign of the mesentery, also known as the whirl sign, is seen when the bowel rotates around its mesentery leading to whirls of the mesenteric vessels.
The term whirlpool sign is used in other contexts: see whirlpool sign (disambiguation).
The World Health Organization classifies anal canal neoplasms into intraepithelial neoplasms and invasive neoplasms which are further divided to epithelial and non-epithelial tumors and secondary lesions:
squamous cell carcinoma of anal canal
adenocarcinoma of anal canal
The WHO classification of anal margin tumors or perianal skin tumors is:
Bowen disease (precursor of squamous cell carcinoma)
Paget's disease (precursor of adenocarcinoma)
squamous cell carcinoma
basal cell carcinoma
Widening of the presacral space is one of the diagnostic indicators of the diseases involving pelvic pathology and rectal involvement. It is ideally measured on barium studies at the level of S3/4 disc level on lateral radiographs and the normal value of the presacral space is <15 mm in adults....
The windsock sign is a typical appearance of a duodenal web (intraluminal duodenal diverticulum) on upper gastrointestinal contrast series which consists of an intraduodenal barium contrast-filled sac that is surrounded by a narrow lucent line (web or intraluminal mucosal diaphragm) which is wel...
Wound dehiscence is a surgical complication whereby there is rupture of a wound along the surgical scar (dehiscence, refers to "splitting open"). This may occur on the skin surface, or along a deeper suture line.
Presentation may be with pain (e.g. sternal dehiscence), or...
The X-marks-the-spot is a sign of complete bowel volvulus and refers to the crossing loops of the bowel at the site of the transition. It has been reported to improve diagnostic confidence in detecting cecal and sigmoid volvulus. This is in contrast to the split-wall sign which indicates partial...
Zebra spleen, also referred to as psychedelic spleen or more correctly inhomogeneous splenic enhancement, refers to the transient heterogeneous parenchymal enhancement of the spleen during the arterial or early portal venous phases of contrast enhancement in CT, MRI, or ultrasound imaging.
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.
More than 50% of the affected patients present in 60-80 years...
Zinc toxicity (also rarely known as zincalism) is rare as the body is remarkably efficient at excreting excess zinc. Typically oral zinc poisoning manifests primarily as:
acute GI symptoms: vomiting, diarrhea, abdominal pain
secondary copper deficiency
zinc competes with copper for absorption...
Zollinger-Ellison syndrome (ZES) is a clinical syndrome that occurs secondary to a gastrinoma.
Diagnosis of ZES is often delayed by 5-7 years after the onset of symptoms 2.
Gastrinomas are usually multiple and typically located in the duodenum (more common) ...
Zuelzer-Wilson syndrome, also known as total colonic aganglionosis, is a subset of Hirschsprung disease, in which the whole colon is aganglionic.
It is uncommon and accounts for 2-13% of cases of Hirschsprung disease 3,7. Compared with Hirschsprung disease which has a marked male ...