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 continuously improved upon by countless contributing members. Our dedicated editors oversee each edit for accuracy and style. Find out more about articles.

16,873 results found
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Hydroxyapatite deposition disease

Hydroxyapatite crystal deposition disease (HADD) or calcium apatite deposition disease (CADD) is a disease of uncertain etiology characterized by periarticular and intra-articular calcium deposits. The shoulder is the most frequently involved site with classic calcific tendinitis presentation. ...
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Subacute hypersensitivity pneumonitis (historical)

Subacute hypersensitivity pneumonitis (also known as subacute extrinsic allergic alveolitis) is a legacy term not recommended in guidelines (c. 2020) 10. It develops when hypersensitivity pneumonitis continues beyond the acute phase (i.e. continues for weeks to months) and still has the potentia...
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Pleural effusion

Pleural effusions are abnormal accumulations of fluid within the pleural space. They may result from a variety of pathological processes which overwhelm the pleura's ability to reabsorb fluid. Terminology "Pleural effusion" is commonly used as a catch-all term to describe any abnormal accumula...
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Internuclear ophthalmoplegia

Internuclear ophthalmoplegia (INO) describes a clinical syndrome of impaired adduction in one eye with dissociated horizontal nystagmus of the other abducting eye, due to a lesion in the medial longitudinal fasciculus (MLF) ipsilateral to the eye unable to adduct. It is a common finding in multi...
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Ligamentum nuchae

The ligamentum nuchae or nuchal ligament is a large median ligament composed of tendons and fascia located between the posterior muscles of the neck. Gross anatomy The ligament nuchae covers the spines of C1 to C6 vertebrae. It is a superior and posterior extension of the supraspinous ligament...
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Dorello canal

Dorello canal channels the abducens nerve (CN VI) from the pontine cistern to the cavernous sinus.  Gross anatomy Dorello canal is an interdural space (between the two layers of dura) found at the medial most end of the petrous ridge at the confluence of the inferior petrosal, basal, and caver...
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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

Pregnancy associated breast cancer

Pregnancy associated breast cancer (PABC) is usually defined as a breast cancer diagnosed during pregnancy or one year following delivery. PABC occurs in one out of every 1500-10,000 pregnancies 5-6 and represents up to 3% of all breast malignancies. The incidence may be increasing due to many w...
Article

Frontal intersinus septal cells

Frontal intersinus septal cells, also known as interfrontal sinus septal cells, are a subtype of medial frontal recess cells. Gross anatomy The frontal intersinus septal cells lie within the intersinus septum between the frontal sinuses. They usually drain in the medial aspect of the frontal r...
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Hemiplegic migraine

Hemiplegic migraines are an uncommon type of migraine with aura wherein patients present with usually reversible motor weakness, typically unilateral. They can be challenging to distinguish from seizure with Todd paresis or ischemic stroke, even with the benefit of MRI 1. Epidemiology Compared...
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MR spectroscopy

The technique of magnetic resonance spectroscopy (usually shortened to MR spectroscopy or MRS) allows tissue to be interrogated for the presence and concentration of various metabolites. Grossman and Yousem said "If you need this to help you, go back to page 1; everything except Canavan (disease...
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Potential recuperation ratio (PRR)

Potential recuperation ratio (or Lausanne Stroke Index) is a simple quantitative measure of the relative size of ischemic penumbra compared to the non-salvageable ischemic core region in acute stroke. To calculate the PRR, a perfusion CT with infarct and penumbra maps is required. To do this, fi...
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Fabry disease

Fabry disease, also known as Anderson-Fabry disease, is a multisystem disorder resulting from an X-linked inborn error of metabolism and is a lysosomal storage disorder. The disease results from genetic mutations in the gene GLA that cause decreased or absent expression of hydrolase alpha-galact...
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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. 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 management of some cond...
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Applying to radiology training in the United Kingdom

Applying to radiology training in the United Kingdom (UK) is through a centralised process for England, Scotland and Wales. Northern Ireland's radiology training recruitment remains a separate process. Applications are open to those completing or completing their Foundation Training or equivale...
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Adrenal myelolipoma

Adrenal myelolipomas are rare, benign and usually asymptomatic tumors of the adrenal gland characterized by the predominance of mature adipocytes.  On imaging, they usually present as large masses with a variable amount of fat-containing components. Epidemiology Myelolipomas are rare tumors o...
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Spondylodiscitis

Spondylodiscitis, (rare plural: spondylodiscitides) also referred to as discitis-osteomyelitis, is characterized by infection involving the intervertebral disc and adjacent vertebrae. Terminology In adults, the use of the term discitis is generally discouraged as isolated infection of the spin...
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Pneumothorax

Pneumothorax, commonly abbreviated to PTX, (plural: pneumothoraces) refers to the presence of gas (often air) in the pleural space. When this collection of gas constantly enlarges with resulting compression of mediastinal structures, it can be life-threatening and is known as a tension pneumotho...
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Common carotid artery

The common carotid arteries (CCA) are paired branchless arteries of the neck that supply blood to the head, face and neck. Each common carotid bifurcates into internal and external carotid arteries. Summary origin: left: branch of the aortic arch right: branch of the brachiocephalic trunk c...
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MRI contrast agent safety

Though considered safer than the frequently used iodinated contrast agents used in x-ray and CT studies, there are safety issues with MRI contrast agents as well. Paramagnetic metal ions suitable as MRI contrast agents are all potentially toxic when injected IV at or near doses needed for clinic...

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