Articles
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16,920 results
Article
Extrusion index
The extrusion index, also known as the (Reimers) hip migration index, is a radiographic measurement of femoral head bony coverage by the acetabulum. It is useful in assessing for developmental dysplasia of the hip, femoroacetabular impingement, and assessment of hip subluxation in cerebral palsy...
Article
Williams-Campbell syndrome
Williams-Campbell syndrome (WCS) is a rare form of congenital cystic bronchiectasis, in which distal bronchial cartilage is defective.
Clinical presentation
Williams-Campbell syndrome may present with recurrent pneumonia, wheezing, pulmonary hypertension, barrel-chest deformity, and Harrison s...
Article
Azygos continuation of the inferior vena cava
Azygos continuation of the inferior vena cava (also known as the absence of the hepatic segment of the IVC with azygos continuation) is an uncommon vascular anomaly and is a cause of a dilated azygos vein.
Terminology
Spelling it "azygous" when referring to the vein is incorrect, regardless of...
Article
Cerebral ring enhancing lesions (mnemonic)
Convenient mnemonics for the causes of cerebral ring enhancing lesions are:
MAGIC DR or DR MAGIC
DR MAGIC L
MAGICAL DR
BITCHES / DITCHES
Mnemonics
MAGIC DR or DR MAGIC
M: metastasis
A: abscess
G: glioblastoma
I: infarct (subacute phase) or inflammatory (neurocysticercosis, tuberculoma)...
Article
Bilateral adrenal gland hyperenhancement
Bilateral adrenal gland hyperenhancement or intense adrenal enhancement is a finding on contrast-enhanced CT which can relate to hypotension, and forms part of the CT hypoperfusion complex.
The underlying mechanism is increased blood flow to the adrenal glands 7. In the arterial phase, enhancem...
Article
CT hypoperfusion complex
CT hypoperfusion complex refers to the predominantly abdominal imaging features that occur in the context of profound hypotension. Multiple abdominal organs can display atypical appearances not related to the initial trauma but reflect alterations in perfusion secondary to hypovolemia which affe...
Article
Chondrosarcoma
Chondrosarcomas are a heterogeneous group of malignant cartilaginous tumors most commonly found in older patients. They can arise de novo or secondary to an existing benign cartilaginous neoplasm. On imaging, these tumors have ring-and-arc chondroid matrix mineralization with aggressive features...
Article
Ectopic ureter
An ectopic ureter is a congenital renal anomaly that occurs as a result of abnormal caudal migration of the ureteral bud during its insertion to the urinary bladder. Normally the ureter drains via the internal ureteral orifice at the trigone of the urinary bladder.
In females, the most common ...
Article
Left hemicolectomy
Left hemicolectomy is a surgical procedure in which splenic flexure, descending colon, and a portion of the sigmoid colon are removed for radical treatment of various pathologies affecting the descending colon.
Indications
colon cancer
inflammatory bowel disease
isolated left diverticular di...
Article
Pseudomyxoma peritonei
Pseudomyxoma peritonei refers to a syndrome of progressive intraperitoneal accumulation of mucinous ascites related to a mucin-producing neoplasm. It is most commonly caused by a mucinous tumor of the appendix 10.
Much less commonly, mucinous tumors of the colon, rectum, stomach, pancreas, and ...
Article
Poland syndrome
Poland syndrome refers to a congenital unilateral absence of the pectoralis major and minor muscles and is a recognized cause of unilateral hyperlucent hemithorax.
Epidemiology
Poland syndrome is usually sporadic, although rare familial cases have been described 1. It is rare, with an estimat...
Article
Emphysematous cystitis
Emphysematous cystitis refers to a gas-forming infection of the bladder wall.
Epidemiology
The condition is rare and usually confined to certain patient subgroups. Median age affected is 66 years. More common in women, 2:1 F:M 9.
Risk factors
Risk factors include:
diabetes mellitus
conside...
Article
Emphysematous pyelonephritis
Emphysematous pyelonephritis (plural: emphysematous pyelonephritides) refers to a morbid infection with particular gas formation within or around the kidneys. If not treated early, it may lead to fulminant sepsis and, therefore, carries a high mortality.
Clinical presentation
The patient usual...
Article
Esophagopleural fistula
Esophagopleural fistulas are abnormal connections between the esophagus and pleura.
Pathology
They can arise from a number of underlying pathologies which can result in an esophageal rupture 3:
post surgical
endoscopic procedures
post esophageal dilatation
secondary to tumor, e.g. esophag...
Article
Broncho-esophageal fistula
A bronch-esophageal fistula (BOF) refers to an abnormal communication between a bronchus and the esophagus.
For congenital fistulas, please refer to the article on congenital tracheo-esophageal fistula.
Clinical presentation
A small proportion of patient with congenital forms may present in a...
Article
Traumatic spinal cord injury
Traumatic spinal cord injury can manifest as a wide variety of clinical syndromes resulting from damage to the spinal cord or its surrounding structures. It can result from minor injury if the spine is weakened from disease such as ankylosing spondylitis or if there is pre-existing spinal stenos...
Article
Canal-to-body ratio of Torg and Pavlov
The canal-to-body ratio of Torg and Pavlov is a method of evaluating the degree of cervical canal stenosis on lateral cervical spine radiographs.
Terminology
This ratio is variously referred to as the Torg ratio 3, the Pavlov ratio 3,4, the Torg-Pavlov ratio 5, or the canal-to-body ratio 3.
M...
Article
Large language models
Large language models are advanced artificial intelligence systems designed to understand and generate human-like text. These models are built using deep learning techniques and are trained on vast amounts of text data, such as books, articles, and websites. Large language models utilize algorit...
Article
Autoimmune glial fibrillary acid protein (GFAP) astrocytopathy
Autoimmune glial fibrillary acid protein (GFAP) astrocytopathy, or simply GFAP astrocytopathy, is a rare inflammatory central nervous system (CNS) disorder.
Epidemiology
Given the rarity of the condition, epidemiological data pertaining to autoimmune GFAP astrocytopathy are not well establishe...
Article
Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS)
Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is an uncommon disorder characterized by infiltration of the brain by inflammatory cells. It has a predilection for the pons, with fairly characteristic curvilinear regions of enhancement bes...