Articles
Articles are a collaborative effort to provide a single canonical page on all topics relevant to the practice of radiology. As such, articles are written and continuously improved upon by countless contributing members. Our dedicated editors oversee each edit for accuracy and style. Find out more about articles.
1,465 results found
Article
Rectal MRI (an approach)
Rectal MRI is a key imaging investigation in the diagnosis, staging and follow up of rectal cancer. An increase in the utility of rectal MRI as been driven by the recognition of the mesorectum as a distinct anatomic compartment containing and limiting the margins of the rectum, and forming a sur...
Article
Venous intravasation
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...
Article
Right hemicolectomy
A right hemicolectomy is a surgical procedure to remove the cecum and ascending colon.
Indications
cancer of the appendix, cecum or ascending colon (most common) 1
inflammatory bowel disease, particularly Crohn's disease
complicated appendicitis
cecal volvulus
perforation of the right colo...
Article
Gastric diverticulum
Gastric diverticula are sac-like outpouchings that most commonly originate from the posterior surface of the gastric fundus. They are the least common of the gastrointestinal diverticula.
Epidemiology
Gastric diverticula are rare and commonly detected incidentally. The incidence varies from 0...
Article
Water-soluble contrast challenge
A water-soluble contrast challenge (more widely known as a Gastrografin challenge) is a combined diagnostic study and therapeutic intervention utilized in the evaluation and management of small bowel obstruction. It is used when clinical or imaging features determine there to be small bowel obst...
Article
Retroperitoneal fasciitis
Retroperitoneal fasciitis (rare plural: retroperitoneal fasciitides) is a rare potentially life-threatening infection of the retroperitoneum. It is the retroperitoneal equivalent of necrotizing fasciitis or non-necrotizing soft tissue fasciitis, and just like its soft tissue counterpart, maybe n...
Article
Pneumatosis coli
Pneumatosis coli is a descriptive sign presenting radiographically as intramural gas limited to the colonic wall.
Terminology
There are different terminologies in the medical literature, such as pneumatosis intestinalis, pneumatosis coli, and pneumatosis cystoides intestinalis. Pneumatosis in...
Article
Klebsiella
Klebsiella is a genus of Gram-negative, oxidase-negative, rod-shaped bacteria, which is relatively commonly encountered in the healthcare environment. It has numerous species, including K. pneumoniae, K. aerogenes, and K. rhinoscleromatis 1. Klebsiella may cause a range of infections, most commo...
Article
Peritoneal hydatidosis
Peritoneal hydatidosis occurs secondary to the seeding of echinococcosis into the peritoneum, usually secondary to the rupture of hydatid disease of the liver.
Pathology
Seeding involves the entire peritoneum and gives appearance of a multiloculated mass.
Classification
Peritoneal hydatidos...
Article
Lower gastrointestinal bleeding
Lower gastrointestinal bleeding (LGIB) is defined as that occurring distal to the ligament of Treitz (i.e. from the jejunum, ileum, colon, rectum or anus) and presenting as either hematochezia (bright red blood/clots or burgundy stools) or melena.
Epidemiology
The incidence of lower gastrointe...
Article
Rigler sign (bowel)
The Rigler sign, also known as the double-wall sign, is a sign of pneumoperitoneum seen on an abdominal radiograph when gas is outlining both sides of the bowel wall, i.e. gas within the bowel's lumen and gas within the peritoneal cavity. It is seen with large amounts of pneumoperitoneum (>1000 ...
Article
AAST spleen injury scale
The American Association for the Surgery of Trauma (AAST) splenic injury scale, revised in 2018, is the most widely used grading system for splenic trauma.
The 2018 update incorporates "vascular injury" (i.e. pseudoaneurysm, arteriovenous fistula) into the imaging criteria for visceral injury 4...
Article
Emphysematous pancreatitis
Emphysematous pancreatitis is an unusual complication of acute pancreatitis caused by necrotizing infection of the pancreas. It is associated with gas-forming bacteria and characterized by the presence of gas within or around the pancreas 1.
Pathology
Infection with gas-forming bacteria such ...
Article
Anal cancer (staging)
The TNM staging of anal cancer is as follows:
Primary tumor (T)
TX: primary tumor cannot be assessed
T0: no evidence of primary tumor
Tis: carcinoma in situ (Bowen disease, high-grade squamous intraepithelial lesion [HSIL], anal intraepithelial neoplasia II-III (AIN II-III)
T1: tumor 2 cm o...
Article
Extrapulmonary tuberculosis
Extrapulmonary tuberculosis (TB) refers to the hematogenous spread of Mycobacterium tuberculosis.
Pathology
Extrapulmonary tuberculosis 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 ...
Article
Irritable bowel syndrome
Irritable bowel syndrome (IBS) is the commonest of the functional gastrointestinal disorders (FGIDs). Its key presenting features are recurrent abdominal pain and change in bowel habit (diarrhea and/or constipation), which may be severe, such that for an individual, there may be a marked negativ...
Article
Anal atresia
Anal atresia, or imperforate anus, refers to a spectrum of anorectal abnormalities ranging from a membranous separation to complete absence of the anus.
Epidemiology
The estimated incidence is 1 in 5000 live births.
Associations
There are frequent associations with other congenital abnormali...
Article
Small bowel mesentery internal hernia
Small bowel mesentery internal hernias (alternative plural: herniae) are a form of internal bowel herniation involving protrusions of viscera through defects in the peritoneum or bowel mesentery.
Epidemiology
This type of internal herniation is more often seen in neonates than in adults ref.
...
Article
Chemical shift artifact
Chemical shift artifact or misregistration is a type of MRI artifact. It is a common finding on some MRI sequences and used in magnetic resonance spectroscopy (MRS). This artifact occurs in the frequency-encoding direction and is due to spatial misregistration of fat and water molecules.
Chemi...
Article
Crohn disease
Crohn disease, also known as regional enteritis, is an idiopathic inflammatory bowel disease characterized by widespread discontinuous gastrointestinal tract inflammation. The terminal ileum and proximal colon are most often affected. Extraintestinal disease is common.
Epidemiology
The diagnos...