Articles

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1,463 results found
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...
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Rectal cancer response assessment

Assessment of rectal cancer response to therapy, which may be chemotherapy, radiotherapy, or a combination, relies on the synthesis of clinical, endoscopic and radiologic evaluation.  The purpose of neoadjuvant therapy is to downstage the tumor, to facilitate surgical resection, and reduce loca...
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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...
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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...
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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...
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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...
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Ascites

Ascites (hydroperitoneum is a rare synonym) is defined as an abnormal amount of intraperitoneal fluid. Terminology Ascites (plural is the same word) tends to be reserved for relatively sizable amounts of peritoneal fluid. The amount has not been defined formally. It is noted physiologically, h...
Article

Gastropericardial fistula

Gastropericardial fistulas are rare abnormal communications between the stomach and the pericardial sac. This is a life-threatening condition that can lead to impaired cardiac function, sepsis and eventually death. Clinical presentation Patients with gastropericardial fistula may present with ...
Article

Cystic lesions of the pancreas (differential)

The differential for cystic lesions of the pancreas includes: unilocular pancreatic pseudocyst intraductal papillary mucinous neoplasm (IPMN) serous cystadenoma uncommonly uni/macrolocular simple pancreatic cyst cystic neuroendocrine tumor of the pancreas diffuse pancreatic cysts pancrea...
Article

Rectoanal intussusception

Rectoanal intussusception refers to the telescoping or infolding of the rectal wall within the rectum itself, or into the anal canal, or externally, during defecation. Terminology Rectoanal intussusception is also termed internal intussusception and internal procidentia1 . Epidemiology Recto...
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Intraductal papillary mucinous neoplasm

Intraductal papillary mucinous neoplasms or tumors (IPMNs or IMPTs) are epithelial pancreatic cystic tumors of mucin-producing cells that arise from the pancreatic ducts. They are most commonly seen in elderly patients.  On imaging, particularly MRCP, they are characterized by single or multipl...
Article

Intestinal transplant

Intestinal transplantation is a surgical treatment for intestinal failure. It is one of the most rarely performed transplant procedures performed, exclusively involving the transplantation of donor small bowel to a recipient, with an ileostomy formation.  Due to the high risk of complications w...
Article

Benign post-traumatic pseudopneumoperitoneum

Benign post-traumatic pseudopneumoperitoneum is the presence of ectopic gas typically between the 5th-10th intercostal spaces after high-energy trauma in the absence of other causes of pseudopneumoperitoneum such as pneumomediastinum 9.  Epidemiology Occurs with an incidence of 5% post-trauma...
Article

Barium sulfate contrast medium

Barium sulfate (BaSO4), often just called barium in radiology parlance, is an ionic salt of barium (Ba), a metallic chemical element with atomic number 56. Barium sulfate forms the basis for a range of contrast media used in fluoroscopic examinations of the gastrointestinal tract. Unlike barium ...
Article

Appendix

The appendix or vermiform appendix (plural: appendices) is a blind muscular tube arising from the cecum, the first part of the large bowel. Gross anatomy The appendix arises from the posteromedial surface of the cecum, approximately 2-3 cm inferior to the ileocecal valve, where the three longi...
Article

Rectal cancer (staging)

Staging of rectal cancer uses the TNM staging system and strongly predicts the success, and rate, of local recurrence following rectal cancer resection. MRI is the modality of choice for the staging of rectal cancer, to guide surgical and non-surgical management options. MRI is used at diagnosis...

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