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.

More than 200 results
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

WHO classification of eye tumors

The World Health Organizatiοn (WHO) classification of eye tumors is a widely used pathologic classification system of neoplasms of the orbit. The revision, part of the 4th edition of the WHO series, was published in 2018 and is reflected in the article below 1. Classification Tumors of the con...
Article

Feces

Feces, also known as stool, is the solid component of human waste. Almost half of its dry mass is bacterial biomass, with the remainder comprised of undigested dietary matter, exfoliated cells of the gut, intestinal secretions, small metabolites and mucus.  Composition Fecal matter is semisoli...
Article

Panniculitis

Panniculitis (plural: panniculitides 1) is a non-specific histopathological term referring to inflammation of adipose tissue. It most commonly affects subcutaneous fat, although internal forms, e.g., mesenteric panniculitis, are well-known 1,2. Clinical presentation Most panniculitides present...
Article

Tumor markers

Tumor markers are a group of molecules in serum that are elevated in various malignancies and are often used to monitor treatment response as well as alert for potential progressive disease when in remission. Commonly used markers include: AFP (alpha fetoprotein) beta-hCG CA 15-3 CA 19-9 C...
Article

Sulfur

Sulfur (chemical symbol S) is one of the essential trace elements. It has an important biological role as part of sulfur-containing amino acids and other important biochemical species such as glutathione, hydrogen sulfide, and coenzyme A. Terminology Sulfur has been the preferred spelling of t...
Article

Septum

Septa (singular: septum) are anatomical or pathological sheet-like structures that subdivide a component of normal anatomy or a lesion. Terminology Septa is the plural of the Latin word septum. Septae and septi are erroneous forms and are not words in English, nor correct plurals in Latin 2. S...
Article

Alpha-fetoprotein

Alpha-fetoprotein (AFP) is an important plasma protein synthesized by the yolk sac and fetal liver. In adults, its main utility is as a tumor marker, primarily for hepatocellular carcinoma or teratoma. Functionally it is the fetal homologue of albumin, i.e. it acts as a major carrier protein in ...
Article

Fomites

Fomites (singular: fomes) are used in medicine to refer to inanimate porous or non-porous objects, or surfaces colonized with microbes (viruses, bacteria, fungi) and serve as vehicles for transmitting many pathogenic microorganisms 1-3. Some examples of fomites are clothing, mobile phones, handr...
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

Ascitic fluid cholesterol level

Ascitic fluid cholesterol level estimation is a simple and precise test for differentiating malignant ascites from non-malignant (cirrhotic) ascites 5-9.  Pathology Ascites is the abnormal collection of fluid within the peritoneal cavity. Malignant ascites comprises ~10% and is usually seconda...
Article

Eosinophilia

Eosinophilia is defined as an abnormally high level of eosinophils in the blood, this is usually defined as >500 cells/μL (normal eosinophil level: <450 cells/μL). Hypereosinophilia is defined as >1500 cells/μL and is usually due to hematological malignancy 1,2. This article includes recommenda...
Article

Aspergillus clavatus

Aspergillus clavatus is one of the species of Aspergillus that can cause pathology in humans. It is allergenic and causes a hypersensitivity pneumonitis called malt-workers lung. See also Aspergillus Aspergillus fumigatus Aspergillus flavus Aspergillus clavatus
Article

Zinc

Zinc (chemical symbol Zn) is a trace element with a key role as a constituent of enzymes (e.g. carbonic anhydrase), as a part of zinc finger proteins vital for the correct folding of macromolecules (such as DNA), and as an important cellular messenger 3. Chemistry Basic chemistry Zinc is a tr...
Article

Gadolinium

Gadolinium (chemical symbol Gd) is a metallic element that can be chelated into paramagnetic complexes for use as gadolinium contrast media. Chemistry Basic chemistry Gadolinium is a silvery rare earth metal, and a member of the lanthanides, with the atomic number 64 and an atomic weight of 1...
Article

Mycobacterium tuberculosis

Mycobacterium tuberculosis is a thin, slightly curved bacillus. A member of the Mycobacterium tuberculosis complex, it is an obligate aerobic bacterium that is the etiologic agent of the majority of tuberculosis cases.  Epidemiology The worldwide incidence of tuberculosis was 8.7 million in 20...
Article

Oxygen

Oxygen (chemical symbol O) is one of the basic organic elements, and is a constituent of most of the known organic molecules - and therefore all lifeforms - on earth.  Chemistry Basic chemistry Oxygen is a colourless odorless diatomic gas with an atomic number 8 and atomic weight 15.999. It h...
Article

Nitrogen

Nitrogen (chemical symbol N) is one of the basic organic elements and is a key constituent of amino acids, the building blocks of proteins, and of nucleic acids (i.e. DNA and RNA). On earth it is the most abundant element found in its pure form and comprises 78% of all breathable air.  Chemistr...
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

Lipohyalinosis

Lipohyalinosis (also known as fibrinoid necrosis) is a disease affecting the small cerebral arteries associated with lacunar infarction and deep white matter changes related to small vessel chronic ischemia. Pathology The histopathological landmarks of lipohyalinosis are irregular fibrosis and...

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.