Articles

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16,797 results found
Article

Dripping candle wax sign (melorheostosis)

Dripping candle wax sign, also known as flowing candle wax appearance, describes the appearance of sclerotic cortical thickening in melorheostosis. The irregular cortical hyperostosis typically occurs on one side of the involved bone and undulates along much like melted wax down a candle. Patho...
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Melorheostosis

Melorheostosis, also known as Leri disease, is an uncommon mesenchymal dysplasia manifesting as regions of sclerosing bone with a characteristic dripping wax appearance (a.k.a. flowing candle wax appearance).  Epidemiology Although changes occur in early childhood, age at presentation is often...
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Image intensifier

Overview Image intensifiers (II) are used to convert low energy x-radiation into visible light images. Frequently the detector portion of an x-ray C-arm used in operating theaters, the image intensifier has a low scatter input portion made of low absorption substances such as titanium or alumin...
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Angleman syndrome

Angelman syndrome refers to a genetic / neurodevelopmental condition principally affecting the central nervous system. Epidemiology The reported estimated incidence can variable ranging from around 1 in 20,000 to 1 in 12,000 live births. No definite gender predilection has been described. Cli...
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Tumefactive demyelinating lesion

Tumefactive demyelinating lesion (TDL), also sometimes referred to as monofocal acute inflammatory demyelination (MAID), is a locally aggressive form of demyelination, usually manifesting as a solitary lesion (or sometimes a couple of lesions) greater than 2 cm that may mimic a neoplasm on imagi...
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Subaponeurotic fluid collection

Subaponeurotic fluid collections are a rare cause of head swelling in young neonates. They are thought to be due to birth trauma from assisted delivery, e.g. prolonged assisted delivery or ventouse delivery, with associated microfistula development that leads to CSF leakage. Delayed subaponeuro...
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Calcaneal inclination angle

The calcaneal inclination angle, also known as the calcaneal pitch, is useful in assessing medial arch height.  Measurement This angle is formed on a weight-bearing lateral foot radiograph between the calcaneal inclination axis (i.e. most inferior part of the calcaneus) and the supporting hori...
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Pes cavus

Pes cavus, also known as talipes cavus, refers to a descriptive term for a type of foot deformity with an abnormally high longitudinal arch of the foot (caved-in foot). Epidemiology Associations It is often associated with certain neuromuscular disorders such as: Charcot-Marie-Tooth disease:...
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Sheehan vessels

Sheehan vessels refer to vessels that arise from neovascularity that develops due to pulmonary hypertension, particularly, but not exclusively, in the context of Eisenmenger syndrome. Pathology The exact pathogenesis of Sheehan vessels has not been fully elucidated, but it is felt that neovasc...
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Investigating seizures (summary)

This is a basic article for medical students and other non-radiologists Seizures are a common medical emergency and presentation to emergency departments 1-3. All new seizures or changes in seizure activity merit assessment with neurologists, and usually require neuroimaging 3,4. They can be di...
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Multipartite hallux sesamoid

Multipartite hallux sesamoids are a commonly seen normal variant, present in up to 33% of hallux sesamoids. They are more commonly bipartite than tripartite.  The medial (tibial) sesamoid is more likely to be multipartite than the lateral (fibular) sesamoid because it more commonly has more tha...
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Intracranial hemorrhage (summary)

This is a basic article for medical students and other non-radiologists Intracranial hemorrhage refers to bleeding within the intracranial cavity and is, therefore, a catch-all term which includes parenchymal (intra-axial) hemorrhage and the various types of extra-axial hemorrhage including, su...
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Investigating focal weakness (summary)

This is a basic article for medical students and other non-radiologists Investigating focal weakness makes up a large proportion of the workload for neurologists and neuroradiologists. A wide range of serious CNS disorders can present with focal weakness. Appropriate timely imaging can guide di...
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Investigating altered consciousness (summary)

This is a basic article for medical students and other non-radiologists Altered consciousness or confusion is a common reason for admission to hospital, and involvement of radiology 1,2. Although the most common reason for acute confusion is intoxication which will improve - when altered neuro...
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Colorectal cancer

Colorectal cancer is the most common cancer of the gastrointestinal tract and is one of the most frequently diagnosed malignancies in adults. CT is the mainstay for colon cancer locoregional staging and MRI is the mainstay for rectal cancer locoregional staging. Epidemiology Colorectal cancer...
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Ischemic stroke (summary)

This is a basic article for medical students and other non-radiologists Ischemic stroke is a clinical diagnosis where an acute neurological deficit follows brain infarction. Reference article This is a summary article; read more in our article on ischemic stroke. Summary anatomy cerebral v...
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Half-value layer

Half-value layer (HVL) is the thickness of a material required to reduce the air kerma of an x-ray or gamma ray to half its original value. It applies to narrow beam geometry only, as with broad-beam geometry, a greater amount of scatter will reach the detector, overestimating the degree of atte...
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Hemorrhagic stroke (summary)

This is a basic article for medical students and other non-radiologists Hemorrhagic stroke is a clinical diagnosis where an acute neurological deficit follows a bleed into the brain parenchyma. Reference article This is a summary article; read more in our article on intracerebral hemorrhage. ...
Article

Cingulate gyrus

The cingulate gyrus lies on the medial aspect of the cerebral hemisphere. It forms a major part of the limbic system which has functions in emotion and behavior. The frontal portion is termed the anterior cingulate gyrus (or cortex) 1,2.  Gross anatomy Location The cingulate gyrus extends fro...
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Urolithiasis

Urolithiasis refers to the presence of calculi anywhere along the course of the urinary tracts. For the purpose of the article, the terms urolithiasis, nephrolithiasis, and renal/kidney stones are used interchangeably, although some authors have slightly varying definitions of each.  See main a...

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