Articles

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16,868 results found
Article

Fetal cardiothoracic circumference ratio

Fetal cardiothoracic (C/T) circumference ratio is a parameter that can be used in the assessment of fetal cardiac and thoracic/chest wall anomalies. It is the ratio of the cardiac circumference to the thoracic circumference and may be easily measured on fetal ultrasound/echocardiography.  Radio...
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Limberg score

Limberg score is a semiquantitative color Doppler ultrasound assessment of the bowel wall vascularity in inflammatory bowel disease.  grade 0: normal bowel wall with no thickening (<4 mm), well-delineated mural stratification, no mural flow (no color Doppler signal)     grade 1: wall thickenin...
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Desmoplasia

Desmoplasia, also known as a desmoplastic reaction, is the term used by pathologists to refer to the growth of fibrous tissue around disease, usually cancer. However in dermatopathology, desmoplasia may also be seen with benign, as well as malignant, conditions. Terminology Pathologists prefer...
Article

Dermal nerve sheath myxoma

Dermal nerve sheath myxomas are benign peripheral nerve sheath tumors usually originating from the skin or subcutaneous tissues. Terminology The previous term was ‘classic or myxoid variant of neurothekeoma’ but data has shown that they are biologically and clinically distinct from neurothekeo...
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Eisenmenger syndrome

The Eisenmenger syndrome is a complication of an uncorrected high-flow, high-pressure congenital heart anomaly leading to chronic pulmonary arterial hypertension and shunt reversal. Epidemiology In general, the shunts that lead to Eisenmenger syndrome share high pressure and high flow 3. As su...
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Osteopoikilosis

Osteopoikilosis is a sclerosing bony dysplasia characterized by multiple benign enostoses. It is a rare inherited benign condition incidentally found on skeletal x-rays. Its importance is predominantly in correct diagnosis so that it is not mistaken for pathology. Epidemiology The bone islands...
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Contrast medium

Contrast media are a group of chemical agents developed to aid in the characterization of pathology by improving the contrast resolution of an imaging modality. Specific contrast media have been developed for every structural imaging modality, and every conceivable route of administration. Bari...
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Aortic dissection

Aortic dissection is the prototype and most common form of acute aortic syndromes and a type of arterial dissection. It occurs when blood enters the medial layer of the aortic wall through a tear or penetrating ulcer in the intima and tracks longitudinally along with the media, forming a second ...
Article

DNA

DNA (deoxyribonucleic acid) is a nucleic acid that encodes the genetic information (genome) necessary for RNA (ribonucleic acid) transcription (transcriptome) and protein synthesis (proteome) 1. It is contained in the nucleus of eukaryotic cells in the form of chromatin or chromosomes 7,8. Mole...
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Cardiac venous malformations

Cardiac venous malformations (also known as cardiac hemangiomas) consists of a slow flow venous malformation and is composed of numerous non-neoplastic endothelial-lined thin-walled channels with interspersed fat and fibrous septae. Terminology It is important to note that according to nomencl...
Article

Salivary gland tumors

Salivary gland tumors are variable in location, origin, and malignant potential.  Pathology In general, the ratio of benign to malignant tumors is proportional to the gland size; i.e. the parotid gland tends to have benign neoplasms, the submandibular gland 50:50, and the sublingual glands and...
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Machine learning

Machine learning is a specific practical application of computer science and mathematics that allows computers to extrapolate information based on observed patterns without explicit programming. A defining characteristic of machine learning programs is the improved performance at tasks such as c...
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Zero echo time imaging

Zero echo time (ZTE) imaging is a development in MR technology, with the aim to better visualize tissues such as bone with the shortest T2 values.  Physics In ZTE, the signal is acquired immediately after applying the radiofrequency pulse resulting in near-zero echo times. After initial data r...
Article

PSA density

The PSA density (PSAD) is a calculation performed at diagnosis and is the serum prostate specific antigen (PSA) level (ng/mL) divided by the volume of the prostate gland (mL), resulting in a value with the units, ng/mL2 1. Prostate volume is calculated from TRUS measurements 2,3.  Alternatively...
Article

Focal cortical dysplasia

Focal cortical dysplasias (FCD) represent a heterogeneous group of disorders of cortical formation, which may demonstrate both architectural and proliferative features. They are one of the most common causes of epilepsy and can be associated with hippocampal sclerosis and cortical glioneuronal n...
Article

Chronic myocarditis

Chronic myocarditis is a prolonged or ongoing myocardial inflammation in the setting of non-dilated or mildly dilated cardiomyopathy 1-5. There have been significant differences concerning the exact definition of the concept as well as the time interval after the onset of symptoms, with the latt...
Article

Sclerosing angiomatoid nodular transformation of the spleen

Sclerosing angiomatoid nodular transformation (SANT) of the spleen is a rare, non-neoplastic vascular splenic lesion of uncertain etiology.  Terminology The term SANT first appeared in the literature in a 2004 article by Martel et al. which examined a series of 25 cases 3. This relatively unco...
Article

CT myelography

CT myelography (CTM) is a myelography technique used mainly to assess for potential spinal canal stenosis when MRI is contraindicated or when dynamic imaging is required. History CT myelography was first performed in 1976 2 and became the gold standard for imaging the spinal canal and cord unt...
Article

Transcatheter mitral valve intervention

Transcatheter mitral valve interventions (TMVI) or percutaneous mitral valve interventions are less-invasive, highly technical procedures available for the management of selected patients with mitral valve regurgitation and include several transcatheter mitral valve repair (TMVr) and transcathet...
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External auditory canal cholesteatoma

External auditory canal cholesteatomas are a rare subtype of acquired cholesteatoma. Epidemiology The external acoustic canal is a rare location for a cholesteatoma with an estimated incidence of around 1.2 per 1,000 new otological patients ref. The overall incidence rate in one large study wa...

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