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.

16,834 results found
Article

Neurobrucellosis

Neurobrucellosis refers to central nervous system involvement by brucellosis and occurs secondary to ingestion or contact with gram-negative, facultative intracellular coccobacilli of the Brucella species. Up to 10% of infections are complicated by neurological involvement 1.  The remainder of ...
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Describing recency

Describing when medical information was generated (e.g. new evidence, discoveries, etc.) is commonplace, and often essential, within articles. When providing these descriptions, the preference is to avoid use of 'recent', variations thereof (e.g. 'recently'), and synonyms thereof (e.g. 'new', '...
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Demyelinating disorders

Demyelinating disorders are a subgroup of white matter disorders characterized by the destruction or damage of normally myelinated structures. These disorders may be inflammatory, infective, ischemic or toxic in origin and include 1-7: autoimmune demyelination multiple sclerosis (MS) Marburg ...
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Pulmonary hypertension

Pulmonary hypertension is currently defined as a resting mean pulmonary arterial pressure of >20 mmHg at right heart catheterization, which is a hemodynamic feature that is shared by all types of pulmonary hypertension. A resting mean pulmonary arterial pressure of ≤20 mmHg is considered normal...
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Lobar intracerebral hemorrhage

Lobar intracerebral hemorrhage is a subtype of intracerebral hemorrhage defined by their location in the peripheral cerebral hemispheres. Compared to deep intracerebral hemorrhages (involving the deep grey nuclei or brainstem), lobar hemorrhages are less likely to be related to hypertension and ...
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Cecal volvulus

Cecal volvulus describes torsion of the cecum around its mesentery which often results in obstruction. If unrecognised, it can result in bowel perforation and fecal peritonitis. Epidemiology Cecal volvulus accounts for ~10% of all intestinal volvuluses, and generally occur in somewhat younger ...
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Osmotic demyelination syndrome

Osmotic demyelination syndrome refers to acute demyelination seen in the setting of osmotic changes, typically with the rapid correction of hyponatremia. It is the preferred term replacing central pontine myelinolysis, recognizing that extrapontine structures can also be affected, previously kno...
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Hypothalamic hamartoma

Hypothalamic hamartomas, also known as tuber cinereum hamartomas, are benign non-neoplastic heterotopias in the brain that typically occur in the region of the hypothalamus, arising from the tuber cinereum, a part of the hypothalamus located between the mammillary bodies and the optic chiasm. E...
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Polycystic ovarian syndrome

Polycystic ovarian syndrome (PCOS), also known as hyperandrogenic anovulation, is a chronic anovulation syndrome associated with androgen excess.  The Rotterdam criteria is used to make the diagnosis of PCOS and require any two of the following three criteria for the diagnosis, as well as the e...
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Polycystic ovaries

Polycystic ovaries (PCO) or polycystic ovarian morphology (PCOM) is an imaging descriptor of a particular type of change in ovarian morphology. A proportion of women with polycystic ovaries will have the polycystic ovarian syndrome (PCOS), which in turn requires additional clinical, as well as b...
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Osteoporosis

Osteoporosis is a metabolic bone disease characterized by decreased bone mass and skeletal fragility. The World Health Organization (WHO) operationally defines osteoporosis as a bone mineral density T-score less than -2.5 SD (more than 2.5 standard deviations under the young-adult mean), which ...
Article

Sonic hedgehog-activated hepatocellular adenoma

Sonic hedgehog-activated hepatocellular adenomas (sh-HCA) are a subtype of hepatocellular adenomas. On imaging, it is still mostly diagnosed by exclusion of the other adenomas subtypes and other liver tumors. Epidemiology Most of sh-HCA were previously grouped under the unclassified adenomas,...
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Incidental thyroid nodule

Incidental thyroid nodules, sometimes called thyroid incidentalomas, are discrete lesions in the thyroid gland found on cross-sectional imaging performed for indications other than thyroid evaluation. They are common but occasionally represent thyroid cancer 1. This article discusses the epidemi...
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Brain metastases

Brain metastases are estimated to account for approximately 25-50% of intracranial tumors in hospitalized patients. Due to great variation in imaging appearances, these metastases present a common diagnostic challenge that can importantly affect the management approach for individual patients. ...
Article

CSF-venous fistula

CSF-venous fistulas are an underdiagnosed cause of spontaneous intracranial hypotension. They are direct communication between the spinal subarachnoid space and epidural veins allowing for the loss of CSF directly into the circulation and can be either iatrogenic or spontaneous in etiology.  Ep...
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Periprocedural anticoagulation

Periprocedural anticoagulation planning is essential when planning an interventional procedure so that the best balance between the risk of bleeding and thrombosis can be achieved. The following must be considered in assessment of periprocedural anticoagulation: bleeding risks associated with ...
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Lymphatic system

The lymphatic system (also known as the lymphoid system or systema lymphoideum in Terminologia Anatomica) is the collective term given to the lymphatic vessels and lymphoid tissues in the body 1,4. Terminology Occasionally the lymphatic system is considered with the reticuloendothelial system ...
Article

Nigrosomes

Nigrosomes are small clusters of dopaminergic cells within the substantia nigra that exhibit calbindin D28K negativity on immunohistochemistry. Five nigrosomes measuring up to a few millimeters in size have been described with the largest labeled as nigrosome-1 1. Nigrosome-1 Nigrosome-1 withi...
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White coat hypertension

White coat hypertension (WCH or WCHT), and not to be confused with the white coat effect (WCE), is commonly defined as typical in-clinic blood pressure (BP) measurements of 140/90 mm Hg or more in the presence of multiple daytime out-of-clinic home or ambulatory BP readings averaging less than 1...
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Alzheimer disease

Alzheimer disease is a common neurodegenerative disease, responsible for 60-80% of all dementias, and imposing a significant burden on developed nations. It is associated with an accumulation and deposition of cerebral amyloid-β (Aβ) and is the most common cerebral amyloid deposition disease.  ...

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