Articles

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16,860 results found
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Postaxial polydactyly

Postaxial polydactyly refers to polydactyly where the additional digit is on the ulnar margin of the hand, or lateral to the 5th (little) toe. Epidemiology Postaxial polydactyly is more common than preaxial polydactyly, with an estimated incidence of 1 in 3000 5. Associations trisomy 13 Bar...
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Polydactyly

Polydactyly (less commonly called hyperdactyly) refers to the situation where there are more than the usual number of digits (five) in a hand or foot. It can be broadly classified as: preaxial polydactyly: extra digit(s) towards the thumb/hallux (radially) postaxial polydactyly: extra digit(s)...
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Brain death

Brain death (or death by neurological criteria) refers to the irreversible end of all brain activity and is usually assessed clinically. Radiographic testing may be used as additional support for a clinical diagnosis of brain death, such as when clinical tests are impossible to perform, e.g. fac...
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Intrapelvic cup migration

Intrapelvic cup migration is a serious complication after total hip arthroplasty, in which the prosthetic acetabular cup migrates or drifts into the pelvic inlet. Epidemiology Fortunately, this complication is very rare. There seems to be a female predisposition 1-3. Risk factors Factors inc...
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Empty light bulb sign (brain death)

In brain death, on Tc-99m HMPAO imaging there is absent or reduced flow in the internal carotid arteries and increased flow within the external carotid arteries. This leads to absent uptake in the brain with subsequent increased perfusion in the nasal region. This appearance has been called the ...
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Hot nose sign

The hot nose sign refers to increased perfusion in the nasal region on nuclear medicine cerebral perfusion studies in the setting of brain death. The absent or reduced flow in the internal carotid arteries is thought to lead to increased flow within the external carotid arteries and subsequent i...
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Using and attributing images from Radiopaedia

Using images from Radiopaedia in your presentations is not only OK but is actively encouraged. Radiopaedia is all about sharing our knowledge and cases and by so doing, makes it easier to teach and to learn from each other.  To download an image, just click the download icon (little cloud with ...
Article

Fecal impaction

Fecal impaction is the inability to spontaneously evacuate solid feces. It is common in the elderly population. A severe form of fecal impaction is often referred to as a fecaloma.  Terminology Fecal loading is a poorly defined term but generally refers to the volume of fecal material in the c...
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Hypertensive microangiopathy

Hypertensive microangiopathy, also referred to as chronic hypertensive encephalopathy, hypertensive arteriopathy, hypertensive arteriolosclerosis, and hypertensive small vessel disease, is a form of sporadic cerebral small vessel disease that results from the sustained effects of elevated system...
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Cerebral small vessel disease

Cerebral small vessel disease, also known as cerebral microangiopathy, is an umbrella term for lesions in the brain attributed to pathology of small arteries, arterioles, capillaries, venules, or small veins. It is the most common cause of vascular dementia/cognitive impairment and is a major ca...
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Langerhans cell histiocytosis (skeletal manifestations)

The skeleton is the most commonly involved organ system in Langerhans cell histiocytosis (LCH) and is by far the most common location for single-lesion LCH, often referred to as eosinophilic granuloma (EG) (the terms are used interchangeably in this article). For a general discussion of this dis...
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Cerebral amyloid angiopathy

Cerebral amyloid angiopathy (CAA) is a cerebrovascular disorder caused by the accumulation of cerebral amyloid-β (Aβ) in the tunica media and adventitia of leptomeningeal and cortical vessels of the brain. The resultant vascular fragility tends to manifest in normotensive elderly patients as lob...
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Lisfranc injury

Lisfranc injuries, also called Lisfranc fracture-dislocations, are the most common type of dislocation involving the foot and correspond to the dislocation of the articulation of the tarsus with the metatarsal bases. Pathology Anatomy The Lisfranc joint articulates the tarsus with the metatar...
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Pelvic varices

Pelvic varices are dialated viens in broad ligaments and ovarian plexus and when is associated with chronic pelvic pain it is called pelvic congestion syndrome (some prefer pelvic venous insufficiency 9) is a condition that results from retrograde flow through incompetent valves in ovarian veins...
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Reverse total shoulder arthroplasty

Reverse total shoulder arthroplasties (RTSA) or replacements (RTSR) are a variant on the standard total shoulder replacement (TSR). It is often the preferred method when there has been advanced damage to the rotator cuff as seen in rotator cuff tear arthropathy. Prosthetic components Humeral c...
Article

Wandering spleen

Wandering spleen is a rare condition in which the spleen migrates from its usual anatomical position, commonly to the lower abdomen or pelvis. Epidemiology Wandering spleen is rare, with a reported incidence of <0.5%. Diagnosis is most commonly made between the ages of 20-40 years and is more...
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Supraclavicular triangle

The supraclavicular triangle is one of the paired triangles in the posterior triangle of the neck. The triangles of the neck are surgically focussed, first described from early dissection-based anatomical studies which predated cross-sectional anatomical description based on imaging (see deep sp...
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Shiny corner sign (ankylosing spondylitis)

The shiny corner sign is a spinal finding in ankylosing spondylitis, representing reactive sclerosis secondary to inflammatory erosions at the superior and inferior endplates (corners on lateral radiograph) of the vertebral bodies, which are known as Romanus lesions. Eventually, the vertebral bo...
Article

Ataxia-telangiectasia

Ataxia-telangiectasia, also known as Louis-Bar syndrome, is a rare multisystem autosomal recessive disorder, sometimes classified as a phakomatosis. It is characterized by multiple telangiectasias, cerebellar ataxia, pulmonary infections, and immunodeficiency.  On brain imaging, it usually demo...
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Medical abbreviations and acronyms (I)

This article contains a list of commonly used medical abbreviations and acronyms that start with the letter I and may be encountered in medicine and radiology (please keep both the main list and any sublists in alphabetic order). A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q...

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