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 edited by countless contributing members over a period of time. A global group of dedicated editors oversee accuracy, consulting with expert advisers, and constantly reviewing additions.

15,768 results found
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Subhepatic appendicitis

Subhepatic appendicitis refers to inflammation of the appendix in which the appendix and cecum have failed to descend inferiorly during normal development; resulting in a "subhepatic" placement. Epidemiology Presentation of an inflamed subhepatic appendix is exceedingly uncommon, representing ...
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Patellofemoral angle

The patellofemoral angle is a measure of patellar tilt and is useful in the diagnosis of patellofemoral instability and excessive lateral pressure syndrome.  Measurement The patellofemoral angle is formed between a line drawn along the bony lateral patellar facet and another line drawn along t...
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Diffuse hemispheric glioma H3 G34 mutant

Diffuse hemispheric gliomas, H3 G34 mutant are rare and high grade infiltrating tumors typically presenting in adolescents and young adults. Terminology Diffuse hemispheric gliomas H3 G34 mutant have been recently included in the 5th Edition (2021) of the WHO brain tumor classification 1 among...
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Regional migratory osteoporosis

Regional migratory osteoporosis is a rare arthralgia affecting the weight-bearing joints of the lower limb.  Epidemiology Regional migratory osteoporosis is most common in middle-aged men 1. Clinical presentation The classic clinical presentation is a history of non-traumatic joint pain, whi...
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Ilizarov apparatus

The Ilizarov apparatus (aka Ilizarov frame) is an external metallic orthopedic fixation device used to length or reshape limbs from congenital deformity or following injury. The procedure was pioneered by the Polish surgeon Gavrill Abramovich Ilizarov.  
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Rheumatoid arthritis associated interstitial lung disease

Rheumatoid arthritis associated interstitial lung disease (RA-ILD) is one of the pulmonary manifestations of rheumatoid arthritis. Epidemiology There may be a greater male predilection with onset of lung disease typically occurs in the 5th to 6th decades of life 5. Radiographic features CT ...
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Trichilemmal cyst

Trichilemmal cysts, also known as pilar cysts, are benign accumulations of keratin along the outer hair root sheath, most commonly on the scalp. They are the most common subcutaneous nodule incidentally found on head imaging and are of no clinical relevance when asymptomatic 1. Uncommonly, they ...
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Medulloepithelioma of the optic disc and optic nerve

Medulloepitheliomas of the optic disc and optic nerve are extremely rare primary intraocular embryonal tumors arising from the optic disc and optic nerve. Terminology A medulloepithelioma of the optic disc and optic nerve may also be referred to as a diktyoma or teratoneuroma, although the use...
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Ovary size and volume

Ovary size and volume is frequently determined with ultrasound. The volume estimate is calculated by the formula for an ellipsoid D1 x D2 x D3 x 0.52 Normal, adult, non pregnant, mean ovary volume of women who are not postmenopausal is 6-7 cc based on several studies based of tens of thousands...
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Tumor pseudoprogression (disambiguation)

Tumor pseudoprogression, also known just as pseudoprogression, corresponds to an increase of lesion size related to treatment, and in some cases even development of transient new lesions, which mimicks true disease progression.  Tumor pseudoprogression is increasingly recognized, and can be enc...
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Tumor pseudoprogression (lung cancer)

Radiologic tumor pseudoprogression on imaging denotes an imaging appearance of tumor response where the tumor first exhibits findings suggestive of progression (i.e. growth, new lesions). However, during sustained therapy, response is eventually demonstrated 1. Epidemiology With the advent of ...
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Reye syndrome

Reye syndrome is a rare pediatric condition characterized by acute onset encephalopathy, severe vomiting and fatty liver failure. It typically presents in children recovering from a viral illness, most commonly influenza or chickenpox 1.  Epidemiology Reye syndrome is usually seen between the ...
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Cacosmia

Cacosmia refers to a form of olfactory dysfunction where the patient has an inability to "recognize" smells. It can arise from a number of pathologies and can include peripheral sinonasal and central sensorineural components. In this situation, the patient knows there is a smell but cannot disti...
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Endometrial osseous metaplasia

Endometrial osseous metaplasia is a very rare pathological condition where there can be mature bone formation in the endometrium. They can be a cause of menorrhagia and infertility. See also endocervical osseous metaplasia / cervical osseous metaplasia (may represent the same spectrum of disea...
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Endocervical microcalcifications

Endocervical microcalcifications can often be an incidental finding and may represent part of the same spectrum of endometrial microcalcifications. They are generally favored benign 1. They may be seen as tiny echogenic foci in the endocervical region on ultrasound. See also endocervical osse...
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Comma sign of subscapularis tear

The comma sign of subscapularis tear was first described on arthroscopy but recognized later on MRI. The comma sign represents a full thickness partial width superior subscapularis tear along with torn superior glenohumeral and coracohumeral ligament insertional fibers vertically retracted via a...
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Pulmonary valve calcification

Pulmonary valve calcification is an uncommon occurrence and usually occurs in the presence of longstanding elevation of right ventricular pressures (such as that of severe pulmonary hypertension). It can also be associated with pulmonary valve stenosis. Some authors suggest if valve calcificatio...
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Pediatric shoulder (AP view)

The anteroposterior shoulder view in pediatrics is part of a two view series examining the shoulder joint, clavicle, scapula and proximal humerus.  Indications This projection demonstrates the shoulder joint in natural anatomical position and is used as an orthogonal view to the lateral should...
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Broden's view

The Broden's view (or Broden view) is a specialized projection that accurately 1 examines the large posterior calcaneal facet and the subtalar joint 2. As technology advances, computed tomography (CT) has widely been used to better visualize and characterize fragment displacements and fracture ...
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Fourth-fifth intermetatarsal angle

The fourth-fifth intermetatarsal angle is used to assess for a bunionette deformity. It should not be confused with the first intermetatarsal angle, used to assess for hallux valgus deformity.  Measurement The fourth-fifth intermetatarsal angle is formed between the long axis of the fourth and...
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Glenoid version angle

The glenoid version angle can be determined by either the Friedman method or the scapular blade method. Glenoid version is important in the preoperative assessment for shoulder arthroplasty and can also be useful in the diagnosis of glenoid dysplasia and causes of recurrent glenohumeral instabil...
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Tuberculous bronchostenosis

Tuberculous bronchostenosis is a potential complication that can occur from endobronchial tuberculosis especially in a chronic form. Pathology Bronchostenosis usually begins as simple erythema and edema with lymphocytic submucosal infiltration followed by tubercle formation. Destruction and re...
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Friedman line

The Friedman or scapular line can be used to determine glenoid version and glenoid bone loss 4. Glenoid version angle measured by the Friedman method has better inter-reader reliability than the scapular body method 2.  Measurement The Friedman line is drawn along the long axis of the scapula ...
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Superior hypogastric nerve block

Superior hypogastric nerve block is a valuable tool for pain relief in the setting of uterine fibroid embolization. This procedure results in significant ischemic pain, peaking at 6-8 hours and lasting approximately 24 hours, then followed by a lesser degree of post-embolization pain which can l...
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AP Meary's angle

AP Meary's angle or AP talus-first metatarsal angle is used to assess for midfoot abduction/adduction in pes planus and pes cavus to assist with pre-operative planning 1.  Measurement On a weight-bearing AP foot radiograph, a line is drawn down the longitudinal axis of the first metatarsal to ...
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Medulloepithelioma of the brain

Medulloepitheliomas of the brain are rare, highly malignant, primitive embryonic tumors derived from the primitive medullary plate and neural tube. These tumors, once considered distinct entities, are now thought to be a pattern of embryonal tumors with multilayered rosettes. Please refer to tha...
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Posterior tibial line

The posterior tibial line is drawn along the posterior aspect of the distal tibial shaft on a lateral ankle x-ray and can be used to assess the sagittal alignment of the talus when comparing side-to-side and/or calculate the posterior tibial line-talar ratio 1,2.
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Suboccipital cavernous sinus

The suboccipital cavernous sinuses are paired venous plexuses that surround the horizontal (distal V3) portion of the vertebral arteries at the craniocervical junction. Its name derives from its resemblance with the cavernous sinus as it is a venous cushion surrounding a large arterial loop at t...
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Supraodontoid space

The supraodontoid space, also known as the supradental space or apical cave, is an extradural space at the anterior craniocervical junction superior to the odontoid process of C2 (dens axis). Gross anatomy Boundaries The space is a cave-shaped region facing posteriorly with the following boun...
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Tuli classification of occipital condyle fractures

The Tuli classification of occipital condyle fractures is a clinically-oriented system for describing these injuries based on fracture displacement and ligamentous injury. It is newer than the more well-known Anderson and Montesano classification of occipital condyle fractures and allows the inc...
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CNS neuroblastoma, FOXR2-activated

Central nervous system neuroblastoma, FOXR2-activated is a novel brain tumor entity recently included in the last WHO brain tumor classification 1. Terminology Central nervous system neuroblastoma with FOXR2 activation was identified in 2016 as a new molecular entity, distinguished from primit...
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Hair

Hair (TA: pilus/pili) remains important physiologically and psychologically for humans. The hair shaft develops from a structure known as the hair follicle. Each hair has an arrector pili muscle and both sensory and sympathetic neural connections. Gross anatomy The hair shaft (TA: stipes pili)...
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Tram-track sign (knee)

The tram-track sign refers to the posterior cruciate ligament (PCL) appearance when it has a diffuse or partial thickening of the anteroposterior diameter greater than 7 mm. It is associated with longitudinal intraligamentous signal abnormalities showing fluid signal characteristics (hyperintens...
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Posterior superior aortic recess

The posterior superior aortic recess, (also known as the superior pericardial recess or the superior sinus) is one of the variable invaginations of the superior aortic recess and is located posterior to the ascending aorta. It may mimic mediastinal lymphadenopathy or a bronchogenic cyst.
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Posterior pericardial recess

The posterior pericardial recess is one of the pericardial recesses forming a small space within the pericardium. It arises from the superior margin of the oblique pericardial sinus, posterior to the right pulmonary artery and medial to the bronchus intermedius. It may mimic mediastinal lymphad...
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Medial cuneiform to second metatarsal distance

Medial cuneiform to second metatarsal distance is the measurement of the distance between the lateral aspect of the medial cuneiform and the medial aspect of the base of the second metatarsal bone 1,2. Usage Medial cuneiform to second metatarsal distance is an important measurement used in ass...
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Post-traumatic pseudolipoma

Post-traumatic pseudolipomas, also known as post-traumatic lipohypertrophy, are prominent increases in the volume of subcutaneous adipose tissue or even benign tumors arising at the location of a preceding blunt soft tissue trauma 1. Clinical presentation Focal palpable mass, not tender and wi...
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Lateral tibiotalar distance

Lateral tibiotalar distance is a measurement on an ankle anterior drawer lateral view to assess for ankle instability.  Measurement On an ankle anterior drawer lateral view (typically performed using a Telos device 2-4), the distance between the posterior tip of the distal tibial articular sur...
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Furuncle

A furuncle, also known as a boil, is an infected hair follicle with extension through the dermis into the subcutaneous soft tissues (cf. folliculitis, a more superficial hair follicle infection, with pus limited to the epidermis). Epidemiology Risk factors Outbreaks of furunculosis are seen, ...
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Double beak sign

The double beak sign refers to the sudden tapering that two adjacent intestinal loops show in the internal hernia at the transition point of the closed loop obstruction.The marked reduction in caliber results in distension of the afferent and efferent intestinal loops. History and etymology It...
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Eburnation

Eburnation describes the appearance of bone following a degenerative process in which subchondral or otherwise exposed bone acquires a non-anatomical sclerotic, microimpacted, and "polished" articular surface. This phenomenon typically arises in one of two situations: hypertrophic non-union of...
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Folliculitis

Folliculitis (plural: folliculitides) is an inflammation of the hair follicle, which is usually infective and due to bacteria, most commonly Staphylococcus aureus.  Epidemiology Folliculitis is more common in men 1. Risk factors shaving hot tubs, especially Pseudomonas aeruginosa hot clima...
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Nunley-Vertullo classification

The Nunley-Vertullo classification is one of several classification systems used for the categorization of Lisfranc injuries. It is based on clinical, x-ray and bone scan findings and also associates the stages with management options or recommendations regarding those injuries 1-3. Usage The ...
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Intraparotid nodal metastases

Intraparotid nodal metastases refer to metastatic involvement of intraparotid lymph nodes from either a primary parotid tumor or an extraparotid tumor in the head and neck (e.g. nasopharyngeal carcinoma) Pathology Location There may be a predilection towards the superficial lobe or tail regio...
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Long axial hindfoot alignment view

The long axial hindfoot alignment view is a specialized, weight-bearing radiographic view that examines the hindfoot alignment as part of a foot and ankle instability investigation.  The long axial view requires no equipment and has higher inter-observer reliability compared to the standard hin...
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Hindfoot alignment view

The hindfoot alignment view is a specialized, weight-bearing radiographic view that examines the hindfoot alignment as part of a foot and ankle instability investigation.  The long axial view requires no equipment and has higher inter-observer reliability when measuring angular hindfoot alignme...
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Foot (weight-bearing medial oblique view)

The weight-bearing medial oblique view of the foot is a specialized projection that places the foot under normal weight-bearing conditions.  The projection is utilized to assess the foot under stress and better demonstrate structural and functional deformities.  Indications This projection is ...
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Ankle (weight-bearing mortise view)

The weight-bearing mortise (mortice is equally correct) view of the ankle is a specialized projection that places the joint under normal weight-bearing conditions.  The projection is utilized to assess the joint under stress and better demonstrate structural and functional deformities.  Termino...
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Ankle (weight-bearing AP view)

The weight-bearing AP view of the ankle is a specialized projection that places the joint under normal weight bearing conditions.  The projection is utilized to assess the joint under stress and better demonstrate structural and functional deformities.  Indications This projection is utilized ...
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Ankle (weightbearing lateral view)

The weight-bearing lateral view of the ankle is a specialized projection that places the joint under normal weight-bearing conditions.  The projection is utilized to assess the joint under stress and better demonstrate structural and functional deformities.  Indications This projection is util...
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Antipyretics

Antipyretics is the term given to medication that reduces a fever.  Commonly used antipyretics 1: aspirin acetaminophen NSAIDs However these agents are far from being side effect free, and research continues into safer body temperature-lowering agents 2.
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Thalamo-occipital distance

The thalamo-occipital distance is a marker of ventricular size in infants. It is defined as the distance between the most posterior surface of the thalamus at its junction with the choroid plexus and the outermost point of the occipital horn in the parasagittal plane 1. See also ventricular in...
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Anterior horn width

The anterior horn width is a marker of ventricular dilatation. It is predominantly used in prenatal and neonatal imaging to determine ventriculomegaly. Measurement The anterior horn width is the diagonal width of the anterior horn at its widest point in the coronal plane 1. In neonates, this i...
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Anterior to posterior fibular gap

The anterior to posterior fibular gap illustrates the displacement of the proximal and distal fibular fragments in trans-syndesmotic lateral malleolar fractures on the lateral view of the ankle and might indicate a medial injury. Usage The anterior to posterior fibular gap can be used in the s...
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Tibiotalar angle

The tibiotalar angle (TTA) is the angle 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...
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First to second metatarsal distance

The first to second metatarsal distance or M1-M2 distance is the length between the bases of the first and second metatarsal bone and a measurement for the evaluation of midfoot instability. Usage The first to second metatarsal distance is used for the evaluation and classification of midfoot ...
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Hallux interphalangeal angle

The hallux interphalangeal angle is between the proximal and distal phalanx of the great toe and serves for the evaluation of toe deformity at the level of the first interphalangeal joint. Usage The hallux interphalangeal angle is used in the setting of hallux valgus or hallux varus to assess ...
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Distal metatarsal articular angle

The distal metatarsal articular angle (DMAA) evaluates the relationship between the longitudinal axis and the articular surface of the first metatarsophalangeal joint and thus metatarsophalangeal coverage or joint congruity on a weight-bearing dorsoplantar radiograph of the foot. Usage The dis...
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Autoimmune hemolytic anemia

Autoimmune hemolytic anemia is a group of hemolytic anemias characterized by an antibody response to red blood cells. It can present as acute or chronic anemia. It can be idiopathic or can occur with other disorders. Several types have been described: warm-antibody type anemia (WAIHA)  cold-a...
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Pulmonary edema signs (mnemonic)

A mnemonic to remember the radiographic signs of pulmonary edema is: ABCDE Mnemonic A: alveolar opacification B: batwinging C: cardiomegaly D: diffuse interstitial thickening (septal lines) and diversion (vascular upper zone diversion, cephalisation) E: effusions (pleural)
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Medial cuneiform-fifth metatarsal height

Medial cuneiform-fifth metatarsal height is the distance between the most inferior part of the medial cuneiform and the most inferior part of the base of the 5th metatarsal and is used to evaluate the height and integrity of the medial vertical arch 1. Usage Medial cuneiform-fifth metatarsal h...
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IOTA-ADNEX model

The ADNEX (Assessment of Different NEoplasias in the adneXa) model is a risk model developed by the IOTA (International Ovarian Tumor Analysis) group to differentiate benign and malignant neoplasms of the ovary and, among them, four different subgroups (borderline, stage I cancer, stage II-IV ca...
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Bow-tie sign

"Bow-tie sign" refers to the appearance of rotated facets in unilateral facet joint dislocation. Facet joint displacement coupled with a rotational deformity gives a bow-like like appearance on a lateral view radiograph of spine 1.
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Talar shift

Talar shift is a concept, sign and/or measurement describing a displacement of the talus in relation to the articular surface of the distal tibia and the malleolar end segment. The direction of the talar shift is further described in the medical literature and lateral talar shift receives the mo...
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Talar tilt

Talar tilt is a measurement of the angle between the talus and the distal tibia, used in the assessment of ankle instability and ankle osteoarthritis (OA). Usage Talar tilt is an important measurement in the assessment of ankle osteoarthritis. It is measured as part of the Kellgren and Lawrenc...
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Landells classification of atlas fractures

The Landells (and van Peteghem) classification of fractures of the atlas is one of the commonly used systems to describe C1 vertebral injuries. Classification Fractures are classified by their involvement of the C1 anterior arch, posterior arch, and/or lateral mass 1: type I: confined to eith...
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Lead pipe fracture

The term lead pipe fracture is the term for a radiographic appearance given to a simultaneous greenstick fracture of one side of the bone (usually metaphysis) with a buckle fracture of the opposing cortex of the same bone.  There are differing opinions in texts as to whether this term should be...
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Age related macular degeneration

Age-related macular degeneration (AMD) is an eye disease that affects central vision. It occurs when aging causes damage to the macula. The macula is responsible for fine detailed vision also known as central vision.
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Nerve compression syndromes of the shoulder

Nerve compression syndromes of the shoulder is a term used to include diseases of the shoulder that cause weakness, discomfort or numbness of the upper extremity. These include quadrilateral space syndrome, suprascapular neuropathy, long thoracic nerve palsy and multiple others 1. They are usual...
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Greek alphabet

The Greek alphabet has been used in science and mathematics for millennia. The alphabet has 24 letters with an order similar to the Latin alphabet (used for English and many European languages).  In the list, the name of the letter is given first, followed by the upper and lower case symbols 1 ...
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Calcinosis of chronic renal failure

Calcinosis of chronic renal failure is a rare cause of soft tissue calcifications in hemodialysis patients with chronic renal failure. This condition is characterized by the deposition of calcium phosphate crystals in the periarticular soft tissues, resulting in large calcified masses. Terminol...
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Lobular capillary hemangioma of the nasal cavity

Lobular capillary hemangioma of the nasal cavity, also known as nasal pyogenic granuloma, is an uncommon benign, rapidly growing vascular neoplasm of the nasal cavity. Terminology The term “pyogenic granuloma” is a misnomer due to lack of infectious origin according to histological and microbi...
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Posterior ligamentous complex injury

Posterior ligamentous complex injury refers to tears/ruptures of the spinal posterior ligamentous complex, which consists of the ligamentum flavum, interspinous ligaments, supraspinous ligament, and facet joint capsules. Posterior ligamentous complex disruption is a central part of the currently...
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Post traumatic arteriovenous vascular malformation

Post traumatic arterio-venous vascular malformations are an uncommon acquired form arteriovenous malformations which occur following a traumatic to that site. Pathology As with other vascular malformations, they comprise of multiple communicating channels between arterial and venous channels a...
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Dural venous sinus cyst

Dural venous sinus cysts are rare, usually congenital lesions, most commonly observed as fluid-filled intraluminal lesions on cross-sectional imaging. Epidemiology Dural venous sinus cysts are very rare, and are mostly congenital 1.  Pathology  Most dural venous sinus cysts are true fluid-fi...
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Ovarian agenesis

Ovarian agenesis refers to a situation where there is a congenital absence of the ovary.   Epidemiology Unilateral ovary agenesis affects approximately 1 in one in 11,240 women while bilateral agenesis is even rarer 1. Clinical presentation Most patients with agenesis of the ovary are asympt...
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Ventricular arrhythmia

Ventricular arrhythmias are potentially very dangerous cardiac arrhythmias arising from the cardiac ventricles that require immediate attention and medical care and include the following rhythms: premature ventricular complexes ventricular tachycardia torsades de pointes ventricular flutter ...
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Acute encephalopathy

Acute encephalopathy is a general term that describes the clinical presentation of a patient with acute cerebral dysfunction. It is usually caused by viral infections, metabolic disorders, dysfunction of the liver or kidneys, or hypertension. Acute encephalopathy may occur in adults and childre...
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Acute leukoencephalopathy with restricted diffusion

Acute leukoencephalopathy with restricted diffusion (ALERD) is a clinicoradiological spectrum of disease with clinical features of leukoencephalopathy and associated imaging findings where diffusion restriction is the dominant finding. Radiographic features The dominant radiological feature is...
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Atrioventricular block

Atrioventricular block, AV block or heart block is a conduction disturbance and a type of arrhythmia where the impulse transmission between the cardiac atria and ventricles is either transiently or permanently delayed or completely blocked 1. Epidemiology Atrioventricular block can be found in...
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Medical devices in the limbs

Medical devices in the limbs are regularly observed by radiologists on plain film, CT and MRI reporting. Most commonly they include orthopedic hardware. Orthopedic joint replacement hardware (arthroplasty) joint fusion hardware (arthrodesis) internal fixation hardware (ORIF) external fixati...
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Flame sign (carotid)

The flame sign refers to a gradual tapering of contrast opacification in the mid-cervical internal carotid artery, sparing the carotid bulb. The sign can be observed on angiography (digital subtraction angiography 1, CT angiography 1, or contrast-enhanced MR angiography 2) in either of two scena...
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Quadruple screening test

The quad screen (also known as AFP Plus / the Multiple Marker Screening) test, is a maternal antenatal screening blood test that can be used in conjunction with other investigations e.g. ultrasound soft markers to estimate the risk for aneuploidy 1.  This is especially valuable when no first-tr...
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Nasal septal cartilage

The nasal septal cartilage, also known as quadrangular cartilage, forms most of the anterior portion of the nasal septum, and is one of five named nasal cartilaginous components supporting the external nose. Gross anatomy Most of the anterior one-third of the nasal septum is formed by the sept...
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Crescent sign (disambiguation)

The characteristic shape of the crescent has been given to many radiological signs over the years. crescent sign (disambiguation) crescent sign (arterial dissection) crescent sign (inguinal hernia) crescent sign (intravenous pyelogram) crescent sign (lung hydatid) crescent sign (osteonecro...
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Doughnut sign (missed testicular torsion)

The doughnut sign, also known as the bull's-eye, halo or ring sign, is the name of a distinctive appearance of a missed testicular torsion on scrotal scintigraphy.  In a missed torsion (i.e. established testicular infarction), there is a reactive hyperperfusion of the ipsilateral dartos muscle ...
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Subependymal cyst

Subependymal cysts may either be postnatally acquired posthemorrhagic cysts or may be congenital (germinolytic). The congenital cysts may result from infection, ischemic injury, or hemorrhage. Epidemiology Most frequently seen in preterm infants, likely related to their persistent germinal mat...
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Intussusception (summary)

This is a basic article for medical students and other non-radiologists Intussusception occurs when a loop of bowel is pulled into the lumen of a distal bowel loop, and is an important cause of acute abdominal pain, particularly in young children. Reference article This is a summary article; ...
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Peripheral T cell lymphoma

Peripheral T cell lymphoma is an uncommon, heterogeneous group of lymphoma. It can account for around 5-15% of non-Hodgkin lymphoma (NHL). Terminology The word "peripheral" does not mean involvement in the extremities but refers to a tumor cells that arises in lymphoid tissue but outside of th...
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Iodinated oil pulmonary embolism

Iodinated oil pulmonary embolism is a form of particulate material pulmonary embolism which in turn falls under non-thrombolic pulmonary emboli. Situations in which has occurred include oily chemoembolisation of tumors  hepatocellular carcinoma 1,3 lymphangiography 4 hysterosalpingography wi...
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Presentation (case)

Presentation refers to the clinical details that need to be included as part of Radiopaedia cases and can include symptoms, signs, physical examination findings, relevant past history and/or laboratory studies. Complications, if part of the initial disease process (e.g. hemorrhage as a complicat...
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Joint mouse

A joint mouse (plural: joint mice) is a historical synonym for an intra-articular loose body. This evocative term predates the discovery of x-rays and originated in orthopedics. It derives from the way in which some intra-articular osteochondral fragments appeared to move rapidly around the insi...
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Corkscrew sign (diffuse esophageal spasm)

A corkscrew esophagus, also known as a rosary bead esophagus, is a classic appearance of distal esophageal spasm on a barium swallow. It is actually quite a rare appearance which is seen in <5% cases of distal esophageal spasm. The finding is caused by multiple tertiary (non-propulsive) contract...