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
CA 15-3
CA 15-3 is a tumor marker used in monitoring breast cancer. The test detects levels of MUC-1, a mucin protein in the blood. MUC-1 is thought to be important in the invasiveness and metastasization of cancer cells.
Physiology
Mucin-1 is a normal epithelial cellular glycoprotein localized to the...
Article
Glucagon
Glucagon is a polypeptide hormone central to the regulation of glucose homeostasis, acting as an antagonist to insulin. In imaging, it is used as an antiperistaltic agent in GI studies, although its clinical efficacy is controversial.
Structure
Glucagon is a 29-amino acid polypeptide hormone ...
Article
Glial cells
Glial cells, or neuroglia, are cells that surround the neurons of the central nervous system embedded between them, providing both structural and physiological support 1-3. Together they account for almost half of the total mass 1 and 90% of all cells of the central nervous system 3. These numb...
Article
Neuron specific enolase
Neuron specific enolase (NSE) is a cell specific isoenzyme of the glycolytic enzyme enolase. It is sometimes considered as a tumor marker.
Elevated neuron specific enolase levels have shown to occur in association with:
tumors
small cell lung cancer: up to 70% of patients with small cell lu...
Article
Histology of blood vessels
Blood vessels, namely arteries and veins, are composed of endothelial cells, smooth muscle cells and extracellular matrix (including collagen and elastin). These are arranged into three concentric layers (or tunicae): intima, media and adventitia.
the intima (or tunica intima)
inner layer abut...
Article
Haggitt level
The Haggitt level is a histopathological term used for describing the degree of infiltration from a malignant polypoidal lesion.
Levels of invasion
0: carcinoma in situ or intramucosal carcinoma
1: invasion of the submucosa, but limited to the head of the polyp
2: invasion extending into the...
Article
Kikuchi level
The Kikuchi level is a histopathological term used for describing the degree of infiltration of a sessile early invasive colorectal cancer1. Preoperative assessment of the level of invasion using this classification may decrease the incidence of unnecessary surgery for sessile polyps.
Levels o...
Article
Fracture healing
Fracture healing occurs naturally after traumatic bony disruption. This process begins with hemorrhage and progresses through three stages:
inflammatory
reparative
remodeling
This process can be supported by various treatment options with immobilization a mainstay; inappropriate treatment ma...
Article
Charcot-Leyden crystals
Charcot-Leyden crystals consist of collections of bipyramidal crystalloid made up of eosinophilic membrane proteins, which occur in:
asthma
other eosinophilic lung disease 2
certain cases of sinusitis (e.g. allergic fungal sinusitis)
They may be detected in the sputum or sinus secretions wi...
Article
Elevated vitamin B12 (marker)
Elevated vitamin B12 (also known as hypervitaminosis B12 or hypercobalaminemia) is most important as a diagnostic and prognostic marker for malignant disease 1,3.
Very high serum levels of vitamin B12, following dietary megadosing, does not seem to have any observable deleterious effects 2.
Article
Chromium
Chromium (chemical symbol Cr) has been categorized previously as one of the trace elements, and has been said to be important for glucose homeostasis, but this is now contentious (see below).
Chemistry
Basic chemistry
Chromium has the atomic number 24 with an atomic weight of 51.9961 g/mol. L...
Article
Neurofibrillary tangles
Neurofibrillary tangles (NFTs) are abnormal cytoplasmic accumulations of tau proteins, found in neuronal and glial cells of the central nervous system. They are responsible for a number of neurodegenerative diseases (collectively known as tauopathies) including 1:
progressive supranuclear palsy...
Article
Neuron
Neurons are cells of the central nervous system, located within the grey matter, and responsible for all neurological functions of the brain.
Structure
Neurons vary in morphology and size substantially, but all share a number of features 1:
a cell body
nucleus
perikaryon: cytoplasm surroun...
Article
Placode
Placode (or neural placode) refers in terms of radiology to a segment of non-neurulated neural tissue, which has had development frozen in the neural plate stage. A placode can be found in all open spinal dysraphisms and in some closed spinal dysraphisms. In the former, the placode is exposed to...
Article
Apoptosis
Apoptosis (plural: apoptoses), also known as programmed cell death (PCD) is a term to describe the process of regulated cell death. This is in contrast to necrosis, which is unregulated cell death often secondary to external factors 1.
Apoptosis occurs in cells which are destined to die by acti...
Article
Fecal immunochemical test
A fecal immunochemical test (FIT) is a test for human hemoglobin in stool as a screening tool for colorectal carcinoma. It is considered a better test than the traditional guaiac fecal occult blood test (gFOBT) which cannot distinguish human blood from food-derived sources.
Technical backgroun...
Article
Primary lung tumors in children
Pediatric primary lung tumors are rare in children however they must be distinguished from locally aggressive inflammatory conditions and benign disease. 1
Primary lung tumors in the neonates and infants include:
pleuropulmonary blastoma (PPB)
infantile fibrosarcoma of the lung
fetal lung in...
Article
Antineutrophil cytoplasmic antibody
Antineutrophil cytoplasmic antibodies (ANCAs) are a heterogenous class of IgG autoantibodies raised against the cellular contents of neutrophils, monocytes and endothelial cells 1. Under indirect immunofluorescence (IIF) microscopy, three ANCA staining patterns are observed, based on the varying...
Article
Basic organic elements
The basic organic elements are those chemical elements that are fundamental to life and are constituents of every or almost every organic molecule, and therefore all life known on earth.
carbon
hydrogen
oxygen
nitrogen
Article
Ependymocytes
Ependymocytes are one of the three types of ependymal cells, which in turn are one of the four principles types of glial cells, and are found lining the ventricular system of the brain and the central canal of the spinal cord 1.
They do not form a water-tight barrier between the cerebrospinal ...
Unable to process the form. Check for errors and try again.