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 edited by countless contributing members over a period of time. A global group of dedicated editors oversee accuracy, consulting with expert advisers, and constantly reviewing additions.

131 results found
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14-3-3 protein

14-3-3 proteins are found in the cerebrospinal fluid (CSF), and are currently used to help identify patients with sporadic Creutzfeldt-Jakob disease (sCJD).  Seven distinct 14-3-3 proteins have been found in humans. In diagnosing sCJD, the sensitivity of 14-3-3 protein is 92% and its specifici...
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1p19q codeletion

1p19q codeletion stands for the combined loss of the short arm chromosome 1 (i.e. 1p) and the long arm of chromosome 19 (19q) and is recognised as a genetic marker predictive of therapeutic response to both chemotherapy and combined chemoradiotherapy and overall longer survival in patients with ...
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2005 WHO histological classification of odontogenic tumours

The 2005 WHO histological classification of odontogenic tumours lays out a classification system for neoplasms and other tumours related to the odontogenic apparatus. At the time of writing (2016), it is still the most widely used classification system although a new revision is due to come up i...
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2-hydroxyglutarate

2-hydroxyglutarate is a metabolite that accumulates in the brains of patients with IDH-1 mutated (IDH-1 positive) brain tumours, particularly diffuse low-grade gliomas. Although not in widespread clinical use, it is likely that 2-hydroxyglutarate, which resonates at 2.25 ppm, will be able to be ...
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Adenoma-carcinoma sequence

The adenoma-carcinoma sequence refers to a stepwise pattern of mutational activation of oncogenes (e.g. K-ras) and inactivation of tumour suppressor genes (e.g. p53) that results in cancer. An oncogene is a gene that has the potential to cause cancer. In tumour cells, these are often mutated or ...
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Alpha fetoprotein

Alpha fetoprotein (AFP) is an important plasma protein synthesised by the yolk sac and fetal liver. In adults its main utility is as a tumour 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 ...
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Alpha thalassemia/mental retardation syndrome X-linked (ATRX)

Alpha-thalassemia/mental retardation syndrome X-linked (ATRX) gene is an important genomic marker of gliomas and is either intact (ATRX wild-type) or mutated (ATRX-mutant) and is correlated with other important genomic markers including IDH, 1p19q codeletion and p53 expression 1,2.  ATRX and ID...
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Alzheimer type I glia

Alzheimer type I glia are a type of glial cell. They are large multinucleated astrocytes encountered in glial tumours and progressive multifocal leukoencephalopathy (PML) 1. 
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Alzheimer type II glia

Alzheimer type II glia are a type of glial cell. They are a pathological reactive astrocyte seen in the brain, unrelated to Alzheimer disease. They are seen most frequently in Wilson disease, but also in other systemic metabolic disorders, particularly those with elevated ammonia levels, typical...
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Amino acids

Amino acids are the monomeric building blocks of proteins. Amino acids concatenate into chains, which are arbitrarily divided into peptides, polypeptides, or proteins according to chain length. Generally, chains of 10 or fewer amino acids are deemed to be peptides, chain length from 10-100 are p...
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Amylase

Amylase is widely employed as a marker of acute pancreatitis and a significant elevation is diagnostic. Physiology α-amylase is a digestive enzyme that is predominantly secreted by the acinar cells of the exocrine pancreas. It is also secreted by the salivary glands. Pancreatic amylase is enco...
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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
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Astrocytes

Astrocytes are cells of the central nervous system which act as both physical and physiological support for the neurones that are embedded between them. They are particularly abundant in the grey matter, where they are the most abundant glial cells 1. They are highly branched and contribute to ...
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Atypical small acinar proliferation

Atypical small acinar proliferations (ASAP) are premalignant lesions of the prostate, which can be found in as many as 5% of prostate biopsies. They are suspicious glands without adequate histologic atypia to establish a definitive diagnosis of prostate cancer. Some studies showed that there is ...
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BRAF

BRAF is a proto-oncogene, encoding for a serine/threonine protein kinase, mutations of which have been identified in a variety of tumours and congenital syndromes including 1:  tumours central nervous system DNET 3 ganglioglioma 3 pilocytic astrocytoma 3 pleomorphic xanthoastrocytoma 2,3 ...
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Brunner glands

Brunner glands are compound tubular submucosal glands found in the duodenum. They are only found proximal to the sphincter of Oddi. Related pathology Brunner gland hyperplasia Brunner gland adenoma
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CA-125

CA-125 is a high-molecular-weight glycoprotein found on the surface of Mullerian and coelomic epithelial-derived cell types, and is the best known tumour marker for epithelial ovarian cancer 6. Importantly, it may also be elevated in several other conditions (see differential diagnosis section b...
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CA 19-9

CA 19-9 (carbohydrate antigen 19-9 or cancer antigen 19-9) is a serum antigen (monosialoganglioside) that has increased diagnostic use in the management of several malignancies, mainly of hepatopancreaticobiliary origin. It is non-specific, however, and can rise in both malignant and non-maligna...
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CA 27-29

CA 27-29 is a tumour marker and is a soluble form of glycoprotein MUC1. It may be elevated in patients with breast cancer. Tumours of the colon, stomach, kidney, lung, ovary, pancreas, uterus, and liver may also raise CA 27-29 levels. Certain non-malignant conditions are also associated with it...
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Carcinoembryonic antigen

Serum carcinoembryonic antigen (CEA) is a cell-adhesive glycoprotein that was discovered in colorectal cancer in 1965, and is hence one of the oldest and most used tumour markers. Its name derives from its normal expression in fetoembryonic liver, gut and pancreas tissue. Normal range of CEA is...
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Cerumen

Cerumen (or earwax) is a natural secretion produced by, and found within the external auditory canal (EAC). It has important roles as part of the first-line of defence of the ear from micro-organisms and optimising function of the tympanic membrane and EAC. Secretion Cerumen is secreted by the...
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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...
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Choristoma

A choristoma is simply a collection of microscopically normal cells or tissues in an abnormal location. This is different to a hamartoma which is derived only from local tissues. Examples include: adrenal choristoma (myelolipoma) nasopharyngeal choristoma facial nerve choristoma optic nerve...
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Choroidal epithelial cells

Choroidal epithelial cells are one of the three types of ependymal cells, themselves a type of glial cell. They cover the surface of the choroid plexus and produce cerebrospinal fluid (CSF). 1. 
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Chromogranin A

Chromogranin A (CgA) is an acidic secretory glycoprotein found in the secretory granules of neuroendocrine cells and neurones, as is a member of the granin family of proteins. It can be used both for immunohistochemical stains and as a serum marker 4.  Immunohistochemistry Chromogranin A is us...
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Circumferential resection margin

The circumferential resection margin (CRM) is a term used in rectal carcinoma excision surgery (such as total mesorectal excision (TME)). Pathologic evaluation of the resection margin on the excised rectum has been considered important for determining the risk of local recurrence. A margin of ≤...
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Columnar alteration with prominent apical snouts and secretions

Columnar alteration with prominent apical snouts and secretions (CAPSS) is a pathological entity encountered when breast biopsies are done for investigation of punctate or amorphous calcifications. CAPSS involves the terminal ductal and lobular units (TDLU's). It is sometimes classified under t...
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Contrast-induced nephropathy

Contrast-induced nephropathy (CIN) describes an association between intravenous or intra-arterial contrast administration and renal impairment, but increasingly the evidence shows that contrast is not the cause of the renal impairment and that confounding factors such as sepsis are likely to be ...
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Cowdry bodies

Cowdry bodies are neuronal intranuclear inclusions seen in Herpes simplex virus infections 1. Pathology Cowdry bodies are in fact fixation artifacts and not directly the result of the intracellular virus 2. 
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C-reactive protein

C-reactive protein (CRP) is an acute phase reactant commonly measured in clinical practice as a marker of inflammation and to monitor disease severity, disease course and treatment response. It should not be confused with protein C (an anticoagulant) or C-peptide (a component of proinsulin). Ph...
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Cyst

A cyst is an abnormal fluid-filled structure which is lined by epithelium; with one exception: lung cysts contain gas, not fluid. By contradistinction, a pseudocyst lacks an epithelial lining and instead has a vascular and fibrotic capsule. Cysts are extremely common and found in most organs. E...
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Decomposition

Decomposition of the human body occurs soon after death and is of relevance to radiology in the fields of post mortem and forensic radiology. Pathology Decomposition occurs due to two main processes 1,2: autolysis: degradation by destructive enzymes released by dying cells in the body putref...
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Diverticulum

Diverticula are outpouchings of a hollow viscus and can be either true or false. Diverticulum is the singular form and diverticula is the correct Latin plural form. 'Diverticuli' and 'diverticulae' are erroneous and should not be used (cf. septum).  True diverticula contains all layers of the...
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Elevated vitamin B12

Elevated vitamin B12 (also known as hypervitaminosis B12 or hypercobalaminaemia) is most important as a diagnostic and prognostic marker for malignant disease 1,3. Very high serum levels of vitamin B12 do not seem to have any observable deleterious effects 2. 
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Eosinophil

Eosinophils (or less commonly acidophiles) are myeloid granulocytes and form one of the main types of white blood cells. Their counts are routinely measured as part of a full blood count. They have important roles in fighting parasitic infections, but it is increasingly recognised that they have...
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Ependymal cells

Ependymal cells are one of the four main types of glial cells, and themselves encompass three types of cells 1:  ependymocytes: line the ventricles of the brain and central canal of the spinal cord tanycytes: line the floor of the third ventricle choroidal epithelial cells: line the surface o...
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Ependymal rosettes (ependymoma)

Ependymal rosettes correspond to a histologic architectural pattern that very characteristic of ependymomas, as tumour cells form structures similar to the lining of normal ventricles. They are characterised by a halo or spoke-wheel arrangement of tumour cells surrounding an empty central tubule...
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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 ...
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Epithelial membrane antigen (EMA)

Epithelial membrane antigen (EMA) is a commonly used target for immunohistochemisty, found on the surface of many epithelial cells and thus present in a wide variety of tumours. It also is sometimes seen within the cytoplasm of cells (e.g. perinuclear dot in ependymomas). 
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Erythrocyte sedimentation rate

Erythrocyte sedimentation rate (ESR) is a non-specific marker of acute inflammation which is seen in a very wide spectrum of pathologies. In recent years it has been sidelined by the use of C-reactive protein and other acute phase markers but it still has an important role to play in the managem...
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Exophytic (definition)

Exophytic is a descriptive term used by radiologists/pathologists to describe solid organ lesions arising from the outer surface of the organ of origin. Literally exophytic only refers to those lesions arising from the outer surface, however radiologists and pathologists use the term to include...
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Faecal calprotectin

Faecal calprotectin (FCAL) is a protein which is a marker of inflammation of the gut used as a diagnostic tool and marker of disease activity for Crohn disease and ulcerative colitis. Biochemistry Calprotectin is a protein complex from the S-100 family, which is formed of three polypeptide cha...
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Fistula

A fistula (pleural fistulae) is an abnormal connection between two epithelial surfaces such as between hollow organs, skin or vessels. Conventionally, the name of a specific fistula type is a combination of the two organs For discussions of specific fistulas please refer to individual articles....
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Flexner-Wintersteiner rosette

The presence of Flexner-Wintersteiner rosette is characteristic for retinoblastoma but is also seen in pineoblastoma and medulloepitheliomas. 
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Fracture healing

Fracture healing occurs naturally after traumatic bony disruption. This process begins with haemorrhage and progresses through three stages: inflammatory reparative remodelling This process can be supported by various treatment options with immobilisation a mainstay; inappropriate treatment ...
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Gene expression classifier

A gene expression classifier (GEC) test is a developing technology in the analysis of indeterminate thyroid nodules, using cells from a fine needle aspiration. The most common commercially available GEC in the United States is known as AFIRMA. The test is designed to use molecular markers to he...
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Glial cells

Glial cells, or neuroglia, are cells that surround the neurones 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 num...
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Glial fibrillary acid protein (GFAP)

Glial fibrillary acid protein (GFAP) is a commonly used target for immunohistochemistry and is positive in many glial cells and tumours of glial origin. GFAP is the building block for intermediate filaments which are abundant in the cytoplasms particularly of astrocytes. 
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Gliosis

Gliosis is the focal proliferation of glial cells in the CNS in response to insult. By strict definition, gliosis is not synonymous with encephalomalacia which is the end result of liquefactive necrosis of brain parenchyma following an insult. Radiologically they share similar features and the d...
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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 t...
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Haematoma

Haematomas are the name given to localised collections of blood and they can form virtually anywhere in the body. They often form secondary to trauma or surgery but spontaneous formation is also not uncommon, especially in those with coagulation disorders or on anticoagulant therapy. Haematomas...
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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...
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Hepascore

Hepascore is a biochemical severity scoring system based on liver function tests in predicting the extent of liver fibrosis/cirrhosis in patients with hepatitis C infection. Hepascore may also be applicable to other liver diseases and is being trialed for fatty liver disease and hepatitis B infe...
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Hepatoblastoma histological classification

Although hepatoblastomas can be histologically classified into a variety of sub types, it is important to remember that with the possible exception of small cell undifferentiated sub type, prognosis is independent of histology when adjusted for stage gender and age 1. major categories epitheli...
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Histological stains

Histological stains are chemicals dyes used to treat histological specimens to make tissues more readily visible by light microscopy and demonstrate underlying characteristics of the tissue. There are many stains, some with very specific uses, whereas other (e.g. hematoxylin and eosin stain (H&E...
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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...
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Homer Wright rosettes

Homer Wright rosettes are differentiated tumour cells grouped around a central region containing neuropil (therefore its association with tumors of neuronal origin). Pathology Examples of tumours where these can be seen include: medulloblastoma (the presence of Homer Wright rosettes in a post...
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Human epididymis protein 4

Human epididymis protein 4 (HE4) is an emerging serum biomarker in the assessment of epithelial ovarian tumours. HE4 is a member of the whey associated protein (WAP) gene cluster and has uncertain biological function 1. Early results indicate that HE4 has higher sensitivity and sensitivity than...
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Hypersensitivity reaction

Hypersensitivity reactions are the immunological response to both exogenous and endogenous antigens, and forms the basis for many diseases.  Pathology Classification There are four types of hypersensitivity reactions, each mediated by a different mechanism 1-4: type 1 hypersensitivity: immed...
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Immunity

The human body regularly encounters harmful micro-organisms, and because of this it has developed a system of defences to help identify and eliminate infective pathogens in the body, known as the immune system. Humans have two types of immunity: innate immunity and acquired immunity. innate im...
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Immunohistochemistry

Immunohistochemistry is a method of assessing histology with the use of antibodies to specific antigens. It is complementary to the older technique of chemical staining of tissues but is often combined with a counter-stain for context (e.g. haematoxylin to stain cell nuclei blue).  The process ...
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Inflammation

Inflammation is a response to a noxious stimuli which can be either be acute or chronic. The cardinal signs of inflammation include: heat redness swelling pain loss of tissue function Sub types Acute Inflammation Acute inflammation occurs within the first few hours after an injury. In ...
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Intracranial arteries

Intracranial arteries have unique structure when compared to extracranial vessels of similar size: see general histology of blood vessels entry. Proximal larger arteries The proximal arteries, arising from the internal carotid and vertebral arteries have differing distribution of elastic fiber...
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Iron

Iron (chemical symbol, Fe) is one of the trace elements that is essential for normal human health due to its central importance in the structure and function of haemoglobin and the cytochromes. Chemistry Iron is a transition metal with atomic number 26 and an atomic weight of 55.847. It exists...
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Isocitrate dehydrogenase

Isocitrate dehydrogenase (IDH) gene mutations are increasingly being recognised as key genetic prognostic markers for diffuse gliomas, and have been included in a recent (2016) update of diffuse astrocytomas in the WHO classification of brain tumours 7. Somatic mutations of IDH result in enchond...
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John Cunningham virus

John Cunningham virus (but universally called the JC virus) is a ubiquitous double-stranded DNA virus of the polyomaviridae family 1. It is the aetiological agent of progressive multifocal leukoencephalopathy (PML). Cases of cerebellar neuronal involvement (JC virus granule cell neuronopathy) as...
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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...
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Lamellated (term)

The term lamellated (or laminated) is a radiopathological term used to describe the layered appearance of many calculi, including those of the renal tract, the salivary glands, and the biliary tree. The internal structure of these calculi has been likened to that of an onion with multiple concen...
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Langerhans cell

Langerhans cells are dendritic cells of monocyte-macrophage lineage, containing large granules called Birbeck granules. They are normally found in epithelial surfaces, lymph nodes and other organs, and can also be found elsewhere, particularly in association with Langerhans cell histiocytosis. ...
Article

Lipase

Lipase, more specifically pancreatic lipase, is an enzyme produced in the pancreas and is responsible for the digestion of fat molecules. It may be raised (hyperlipasaemia) in numerous pancreatic, hepatobiliary and other diseases but is most commonly associated with acute pancreatitis. Physiolo...
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Lipohyalinosis

Lipohyalinosis is a disease affecting the small cerebral arteries associated with lacunar infarction and deep white matter changes related to small vessel chronic ischaemia. Pathology The histopathological landmarks of lipohyalinosis are irregular fibrosis and hyaline of small cerebral arterie...
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Liquefactive necrosis

Liquefactive necrosis is a form of necrosis where there is transformation of the tissue into a liquid viscous mass. Pathology In liquefactive necrosis, the affected cell is completely digested by hydrolytic enzymes leading to a soft, circumscribed lesion which can consist of fluid with remains...
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Macroamylasaemia

Macroamylasaemia is the presence of serum amylase of a large molecular size, seen in both otherwise healthy individuals, and also in various diseases. Amylase seems to be able to self-polymerise and/or form complexes with other blood proteins, e.g. immunoglobulins. Epidemiology Macroamylasaemi...
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Macrolipasaemia

Macrolipasaemia is the presence of serum lipase of a large molecular size, seen occasionally in otherwise healthy individuals, but more commonly in various diseases. Lipase is able to self-polymerise and/or form complexes with other blood proteins e.g. immunoglobulins. Epidemiology Epidemiolog...
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Macromolecular complex

Macromolecular complexes include both macrohormones and macroenzymes, which consist of hormones and enzymes respectively covalently bound to carrier molecules, e.g. immunoglobulins, or occasionally the molecule may self-polymerise. Their primary importance lies in their ability to produce an art...
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Malignant transformation

Malignant transformation is the term given to the process whereby either normal, metaplastic, or benign neoplastic tissue, becomes a cancer. The process usually occurs in a series of steps and the affected tissue gradually accumulates the genetic mutations that express a malignant phenotype. The...
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Metaplasia

Metaplasia is a general pathology term that refers to process when one cell type is replaced by another. It usually occurs in the context of a changed cellular environment to which the new cell type is better adapted 1. Examples include 2-5: Barrett oesophagus: normal squamous epithelium replac...
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Microglia

Microglia is one of the four types of glial cell and are the central nervous system equivalent of monocyte-macrophage system 1,2. During health, they are essentially inactive with small cell bodies and numerous processes extending throughout the local parenchyma 1,2. When presented a condition w...
Article

Mycobacterium bovis

Mycobacterium bovis is a member of the Mycobacterium tuberculosis complex and an obligate aerobe bacterium that is the cause of tuberculosis in cattle. M. bovis can also cause tuberculosis in other mammals including humans. Epidemiology In the United States, M. bovis accounts for ~ 2% of all n...
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 aetiologic agent of the majority of tuberculosis cases.  Epidemiology The worldwide incidence of tuberculosis was 8.7 million in 2...
Article

Myoinositol peak

Myoinositol 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).  Myoinositol is a precursor of both phosphatidylinositol (the major inositol-containing phospholipid) and of phosphatidylino...
Article

Neuritic plaques

Neuritic plaques (also known as senile plaques) are pathological extracellular aggregates formed around a core of amyloid β peptide and are a hallmark of Alzheimer's disease.  They should not be confused with neurofibrillary tangles which are intracytoplasmic. Pathology Neuritic plaques are e...
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

Neurone

Neurones are cells of the central nervous system, located within the grey matter, and responsible for all neurological functions of the brain.  Structure Neurones vary in morphology and size substantially, but all share a number of features 1: a cell body nucleus perikaryon: cytoplasm surro...
Article

Normal postmortem changes in the gastrointestinal tract

Normal postmortem changes in the gastrointestinal tract​ refers to the normal changes that can be expected to be seen in the gastrointestinal tract on post-mortem imaging. Radiographic features CT The following changes may be present in the abdomen and gastrointestinal tract 1: intraluminal ...
Article

Oligodendrocytes

Oligodendrocytes are one of the four principles types of glial cells and are the central nervous system equivalent of the Schwann cells found peripherally. They wrap the neurones of the brain and spinal cord with myelin 1.  See also oligodendroglioma
Article

P16

P16 is a widely used immunohistochemical marker. It can be expressed in other neoplasms and in several normal human tissues. It can play an important role gynaecological malignancy and is a surrogate marker for HSIL's (high-grade squamous intraepithelial lesions). It has been applied to facilita...
Article

Perivascular pseudorosettes (ependymoma)

Perivascular pseudorosettes are a common histologic feature of central nervous system ependymomas. They represent sections through papillary structures composed of tumour cells arranged radially around a central vessel. Between the central vessel and the tumour cells is a relatively microscopica...
Article

Pick bodies

Pick bodies are intracytoplasmic spherical inclusions found in Pick's disease. They are composed of tau fibrils (thus Pick's disease is a tauopathy) arranged in a disorderly array 1. Although tau protein is a major component a number of other protein products are present, including ubiquitin and...
Article

Picornaviruses

Picornaviruses (pico-RNA-viruses) are non-enveloped, positive-stranded RNA viruses with an icosahedral capsule. Their positive, single stranded RNA architecture places them in Baltimore group IV. The name derives from the fact that they are small (pico) RNA viruses. The picornavirus family cont...
Article

Pneumatosis cystoides intestinalis

Pneumatosis cystoides intestinalis s a radiographic/descriptive entity characterised by the presence of multiple gas-filled cysts in the submucosa and/or gastrointestinal subserosa of the small intestine. It is a subtype of pneumatosis with specific features, which can occur anywhere along the g...
Article

Poliovirus

Poliovirus is the causative agent involved in poliomyelitis. It is a single-stranded RNA virus and one of the smallest significantly described viruses: group: group IV family: picornaviruses genus: enterovirus species: enterovirus C subtype: poliovirus Related pathology poliomyelitis pol...
Article

Pregnancy-associated plasma protein-A

Pregnancy-associated plasma protein-A (PAPP-A) is a protein found in the maternal circulation and is produced by the placenta. The PAPP-A gene has been assigned to human chromosome 9q33.1 and contains 22 exons 5. PAPP-A values tend to rise exponentially during pregnancy and the reference range d...

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