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.
319 results found
Article
Anemia
Anemia is the presence of reduced hemoglobin in the blood. Formally, the World Health Organizatiοn (WHO) defines anemia by the hemoglobin concentration in the blood according to age and sex 1:
adult men: <130 g/L
adult women: <120 g/L
Values for pregnant women and children are different.
Cli...
Article
Gliosis
Gliosis is a reactive process occurring after some time following most types of central nervous system injuries and is the result of focal proliferation of glial cells, particularly astrocytes.
Terminology
Although the terms astrocytic gliosis or astrocytosis are often used interchangeably wi...
Article
Skeletal muscle
Skeletal muscles, skeletal striated muscles or plainly muscles are integral to the locomotor system responsible for movements. The human body's musculoskeletal system has more than 600 muscles 1 making up around 40% of the body weight. They are heterogeneous and have different architectures and ...
Article
Hemoglobin
Hemoglobin (Hb) is the oxygen-carrying molecule in red blood cells.
Structure
Hemoglobin is a tetrameric protein molecule composed of four subunits. Each subunit consists of an iron-containing cyclic heme component linked to a polypeptide chain, the polypeptides are together known as globin. E...
Article
Naming of organisms
Occasionally, we will refer to lifeforms in an article or case, and we adhere to standard scientific convention when it comes to naming of organisms, as set down by the International Commission on Zoological Nomenclature (ICZN) 1. As per the standard binomial system, the genus and species of the...
Article
Zoonosis
A zoonosis (plural: zoonoses), also known as a zoonotic disease, is an infectious disease in humans (the host) for which another vertebrate animal can be the vector. Some zoonoses have an additional vector besides the vertebrate e.g. R. rickettsii is carried by ticks on mammals. Viruses, bacteri...
Article
Endometrial osseous metaplasia
Endometrial osseous metaplasia is a very rare pathological condition whereby there may be mature bone formation within the endometrium. This process may be a cause of menorrhagia and/or infertility.
Differential diagnosis
The common diagnostic mimics are iatrogenic endometrial gaseous foci (us...
Article
Metastatic axillary lymphadenopathy of unknown primary
Metastatic axillary lymphadenopathy of unknown primary can be a very challenging situation.
Pathology
Usual potential sites include:
occult breast cancer: the incidence of an axillary lymph node manifestation from an occult primary breast cancer is low, ranging from 0.3-0.8% of all patients ...
Article
Oncotype DX Breast Recurrence Score
Oncotype DX Breast Recurrence Score (Exact Sciences, USA) is a proprietary 21-gene expression assay that is prospectively validated and provides prognostic information on the 10-year risk of disease recurrence in estrogen receptor positive, lymph node-negative breast cancer patients 1. This gene...
Article
Succinate dehydrogenase (SDHx) gene mutation
Succinate dehydrogenase gene (SDHx) germline mutations increase the risk of sympathetic paragangliomas, head and neck paragangliomas, pheochromocytomas, renal cell carcinoma (RCC), and gastric gastrointestinal stromal tumors (GIST) 1,2,6,7.
Pathology
There are four SDH genes - SDHA, SDHB, SDHC...
Article
ROS1 mutation
The ROS1 mutation is a mutation occurring in the ROS1 oncogene on chromosome 6 resulting in a defective receptor tyrosine kinase which has structural similarity to the anaplastic lymphoma kinase (ALK) protein.
It is thought to be present in several cancers of the subtype non-small cell lung can...
Article
TP53 (gene)
The TP53 gene, located on chromosome 17, is a tumor suppressor gene, responsible for the production of the p53 protein, a transcription regulatory protein which works in concert with a number of other proteins, together forming the p53 pathway 1,2.
Inherited mutations in this gene result in the...
Article
CA-125
CA-125 is a high-molecular-weight glycoprotein found on the surface of Müllerian and celomic epithelial-derived cell types and is the best-known tumor marker for epithelial ovarian cancer 6. Importantly, it may also be elevated in several other conditions (see differential diagnosis section belo...
Article
Vitamin A
Vitamin A are a group of fat-soluble vitamers (the retinoids) required for many physiological functions, mainly vision, reproduction and epithelial maintenance. In the retina, a specific retinoid, 11-cis-retinal, is formed by photoisomerisation within the rods and cones. The retinoids are hemati...
Article
Tungsten
Tungsten (chemical symbol, W) is a hard refractory metallic element with remarkable resilience which forms the basis for its industrial uses. It is the metal of choice in the filaments and targets of x-ray tubes. There is no evidence that tungsten is required by the human body, although some mic...
Article
Prostate-specific membrane antigen
Prostate-specific membrane antigen (PSMA), also known as glutamate carboxypeptidase II, is a type II transmembrane glycoprotein that has become an increasingly prominent imaging biomarker 1. PSMA has emerged as a useful target in PET imaging of prostate cancer, especially in the evaluation of sm...
Article
Clade
A clade is a taxonomic term which is used to describe organisms which form a distinct group with shared characteristics that distinguish them from other groups of organisms. For example, organisms making up genetic variants within a particular species.
See also
mpox
Article
Myo-inositol peak
Myo-inositol is one of the compounds images with MR spectroscopy (MRS) at both 1.5 T and 3 T and is seen to resonate at 3.5 ppm chemical shift (right of the choline peak).
Myo-inositol is a precursor of both phosphatidylinositol (the major inositol-containing phospholipid) and phosphatidylinos...
Article
Synechiae
Synechiae (singular: synechia, alternative plural: synechias) are another term for adhesions, which in radiological contexts usually relates to bands of scar tissue between structures, e.g. within the abdominal cavity or pleural cavity or within the uterus.
Pathology
Synechia can be found thro...
Article
Helicobacter pylori
Helicobacter pylori (H. pylori) is a gram-negative spiral flagellate microaerophilic bacterium found in the human gastric mucosa 1. It is classified as a Group I carcinogen and is considered necessary but insufficient alone to cause gastric adenocarcinoma. More often than not, it results in chro...
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