Articles

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16,873 results found
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Pulmonary cavity

A pulmonary cavity is a collection of gas and/or fluid enclosed by a thick and often irregular wall which usually occurs when central necrotic tissue is expelled via a bronchial connection. Cavities may be single or multiple and can be isolated or associated with lung disease 12. Terminology P...
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Splenic artery embolization

Splenic artery embolization is an endovascular technique for treatment of splenic and splenic artery pathology as an alternative to splenic artery ligation or splenectomy. It often results in successfully treating the underlying pathology, while maintaining at least partial splenic function.  I...
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Dinner fork deformity (wrist)

A dinner fork deformity, also known as a bayonet deformity, occurs as the result of a malunited distal radial fracture, usually a Colles fracture. The distal fragment is dorsally angulated, displaced and often also impacted. The term is descriptive, as the lateral view of the wrist is similar to...
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Tibiotalar angle

The tibiotalar angle is between the anatomic axis of the tibia and the superior articular surface of the talar dome. Differently from the talar tilt, the tibiotalar angle uses the tibial longitudinal axis instead of the distal articular surface as a tibial reference point. Usage The tibiotalar...
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Susceptibility vessel sign

The susceptibility vessel sign is a radiological sign appreciated on susceptibility-sensitive MRI brain sequences that is described in patients with acute ischemic stroke. It correlates well with the hyperdense vessel sign (e.g. hyperdense MCA sign) that may be seen on CT brain, but is considere...
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Acromial types

The shape of the acromion had been initially divided into three types (which was known as the Bigliani classification) 3, to which a fourth has been added 2. They are used as a standardized way of describing the acromion, as well as predicting to a degree the incidence of impingement.  Classifi...
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Osteochondroma

Osteochondromas are a relatively common imaging finding, accounting for 10-15% of all bone tumors and ~35% of all benign bone tumors. Although usually thought of as a benign bone tumor, they may be thought of as a developmental anomaly. They are frequently asymptomatic and have very low malignan...
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Clustering

Clustering, also known as cluster analysis, is a machine learning technique designed to group similar data points together. Since the data points do not necessarily have to be labeled, clustering is an example of unsupervised learning. Clustering in machine learning should not be confused with d...
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Godtfredsen syndrome

Godtfredsen syndrome, also known as clival (clivus) syndrome, is a rare syndrome of abducens and hypoglossal nerve palsies that localizes to a clival mass. Clinical presentation The classic clinical presentation includes 1-3: abducens nerve palsy: diplopia worse when horizontal gaze is direct...
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Clivus

The clivus (of Blumenbach) is the sloping midline surface of the skull base anterior to the foramen magnum and posterior to the dorsum sellae 1. Gross anatomy Specifically, the clivus is formed by the sphenoid body and the basiocciput, which join at the spheno-occipital synchondrosis. At the c...
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Abducens nerve palsy

Abducens nerve palsy, or sixth nerve palsy, results in weakness of the ipsilateral lateral rectus muscle. Clinical presentation Patients present with horizontal diplopia with an inability to abduct the ipsilateral eye, thereby resulting in an esotropia (nasal deviation of the eye). Pathology ...
Article

Pneumatosis coli

Pneumatosis coli is a descriptive sign presenting radiographically as intramural gas limited to the colonic wall.  Terminology There are different terminologies in the medical literature, such as pneumatosis intestinalis, pneumatosis coli, and pneumatosis cystoides intestinalis. Pneumatosis in...
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Thoracic actinomycosis infection

Thoracic actinomycosis refers to an uncommon indolent infection caused principally by the genus Actinomyces (higher prokaryotic bacteria belonging to the family Actinomyceataceae). Epidemiology While it is rare in general, the thoracic form actinomycosis constitutes ∼15% of the total burden of...
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Gadolinium contrast agents

Gadolinium-based contrast media (GBCM), gadolinium-based contrast agents (GBCAs), or simply gadolinium contrast agents, are molecular complexes containing the rare earth metal gadolinium, chelated to a carrier ligand. They are a type of paramagnetic contrast agent, which are the primary class of...
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Empyema vs pleural effusion

An empyema can resemble a pleural effusion and can mimic a peripheral pulmonary abscess. Features that help distinguish a pleural effusion from an empyema include: Shape and location Empyemas usually: form an obtuse angle with the chest wall unilateral or markedly asymmetric whereas pleural ...
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Hypoglossal nerve palsy

Hypoglossal nerve palsies, or twelfth nerve palsies, result in weakness of the muscles supplied by the hypoglossal nerve, namely the intrinsic and extrinsic tongue muscles, except for palatoglossus. Clinical presentation The hypoglossal nucleus receives a major component of contralateral corti...
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Klebsiella

Klebsiella is a genus of Gram-negative, oxidase-negative, rod-shaped bacteria, which is relatively commonly encountered in the healthcare environment. It has numerous species, including K. pneumoniae, K. aerogenes, and K. rhinoscleromatis 1. Klebsiella may cause a range of infections, most commo...
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Strain elastography

Strain elastography (also known as tissue strain elastography/static elastography/compression elastography) is a developing form of ultrasound that assesses tissues' macroscopic structure through the strain modulus. This is different from normal B-mode grayscale ultrasound which characterizes a ...
Article

Corpus callosum

The corpus callosum (plural: corpora callosa) is the largest of the commissural fibers, linking the cerebral cortex of the left and right cerebral hemispheres. It is the largest white matter tract in the brain. Summary located inferior to the cerebral cortices, and superior to the thalamus co...
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Protoplasmic astrocytoma (historical)

Protoplasmic astrocytoma is a historical term previously applied to an uncommon variant of diffuse adult-type astrocytomas. Terminology The term was removed in the updated 4th edition (2016) of the WHO classification of CNS tumors, with these tumors folded into what is now referred to as astro...

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