Articles

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16,906 results found
Article

Squamous cell carcinoma of the penis

Squamous cell carcinoma (SCC) of the penis is an uncommon condition that often presents at an advanced stage. Imaging is more often used for staging than for the initial diagnosis. It is the commonest histological subtype of penile cancer. Epidemiology Penile cancer is a relatively infrequent ...
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Monochorionic monoamniotic twin pregnancy

A monochorionic monoamniotic (MCMA) twin pregnancy is a subtype of monozygotic twin pregnancy. These fetuses share a single chorionic sac, a single amniotic sac, and, in general, a single yolk sac.  Epidemiology It accounts for the minority (~5%) of monozygotic twin pregnancies and ~1-2% of al...
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Lipomyelocele

Lipomyelocele, also known as lipomyeloschisis, is one of the most common closed spinal dysraphisms. It is most commonly encountered in the thoracolumbar region and usually presents as a fatty subcutaneous mass. It should not be confused with myeloschisis which is a severe form of open spinal dy...
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Normal pressure hydrocephalus

Normal pressure hydrocephalus remains a controversial entity with often ambiguous imaging findings. It is classically characterized by the triad of gait apraxia/ataxia, urinary incontinence, and cognitive impairment, although not all patients with the condition have all three 31. On imaging, it...
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Spinal instability neoplastic score (SINS)

The spinal instability neoplastic score (SINS) helps to assess tumor-related instability of the vertebral column. It has been shown to be useful in guiding the mobilization or operative management of patients with neoplastic spinal disease and correlates with patient-reported outcomes 1-4. Stud...
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Spinal dysraphism

Spinal dysraphisms refer to a broad group of malformations affecting the spine and/or surrounding structures in the dorsum of the embryo. They are a form of neural tube defect. Terminology The term dysraphism implies that the cause of the abnormality is due to anomalous midline fusion and shou...
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Spatial compounding (ultrasound)

Spatial compounding is an advanced ultrasound technique that utilizes multiple angles of insonation to create a single averaged image 1. Clinical applications The advantages of spatial compounding are that angle dependent artefacts are reduced, curved surfaces appear more continuous and backgr...
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Esophageal stricture

Esophageal stricture refers to any persistent intrinsic narrowing of the esophagus.  Terminology The term peptic stricture refers specifically to those benign esophageal strictures caused by chronic acid reflux, although some - incorrectly - use it more loosely to refer to any benign esophagea...
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Schatzki ring

A Schatzki ring, also called a Schatzki-Gary ring, is a symptomatic, narrow esophageal B-ring occurring in the distal esophagus and usually associated with a hiatus hernia.  Epidemiology Relatively common, lower esophageal rings are found in ~6-14% of oesophagrams 9.  Associations More than ...
Article

Salter-Harris classification

The Salter-Harris classification was proposed by Salter and Harris in 1963 1 and, at the time of writing (January 2023) remains the most widely used system for describing physeal fractures.  Classification Conveniently the Salter-Harris types can be remembered by the mnemonic SALTR. type I s...
Article

Percutaneous nephrolithotomy

Percutaneous nephrolithotomy (PCNL) is a surgical procedure for the extraction of large renal calculi. It is usually performed in the operating theater either by a urologist or combined urologist-radiologist team. Indication PCNL is used to destroy and remove renal calculi, typically over 2 cm...
Article

Autoimmune glial fibrillary acid protein (GFAP) astrocytopathy

Autoimmune glial fibrillary acid protein (GFAP) astrocytopathy, or simply GFAP astrocytopathy, is a rare inflammatory central nervous system (CNS) disorder. Epidemiology Given the rarity of the condition, epidemiological data pertaining to autoimmune GFAP astrocytopathy are not well establishe...
Article

Alexander disease

Alexander disease, also known as fibrinoid leukodystrophy, is a rare fatal leukodystrophy. Usually clinically evident in the infantile period, neonatal, juvenile, and adult variants are recognized. As with many diseases with a variable age of presentation, the earlier it manifests the more fulmi...
Article

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...
Article

Necrotizing enterocolitis

Necrotizing enterocolitis (NEC) is the most common gastrointestinal condition in premature neonates. It is characterized by inflammation, ischemia, and permeability of the neonatal bowel wall to bacteria. It is potentially life-threatening with significant associated morbidity 1. Epidemiology ...
Article

Multiplanar reformation (MPR)

Multiplanar reformation or reconstruction (MPR) involves the process of converting data from an imaging modality acquired in a certain plane, usually axial, into another plane 1. It is most commonly performed with thin-slice data from volumetric CT in the axial plane, but it may be accomplished ...
Article

Periosteal osteosarcoma

Periosteal osteosarcomas are intermediate-grade bone-forming neoplasms originating on the bony surface in strong association, typically underneath the periosteum. Epidemiology Periosteal osteosarcomas are the second most common type of surface-based osteosarcoma after parosteal osteosarcoma an...
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Parotid gland tumors

Parotid gland tumors include a variety of benign and malignant entities that are also found in other salivary glands (see salivary gland tumors). The frequency of different tumors varies considerably among the salivary glands with the parotid gland hosting the majority of all salivary gland tumo...
Article

Animal and animal produce inspired signs

Animal and animal produce inspired signs may sound a little silly, but the radiology literature is replete with such signs, some more fanciful than others. Fish and marine life cluster of black pearls sign endosteal scalloping: medullary cavity masses, e.g. multiple myeloma fish vertebra (al...
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Chipmunk sign (brainstem)

The chipmunk sign refers to the MRI appearance of the medulla in some patients with leukodystrophies, particularly Alexander disease. The same appearance has been described in adult polyglucosan body disease, vanishing white matter disease, Pelizaeus-Merzbacher disease, 4H syndrome, and adult-on...

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