Articles

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16,886 results found
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Speckle artifact

Speckle artifact may be encountered in ultrasound. It is caused by the scattering of waves from the surface of small structures within a certain tissue. The artifact produces a textured appearance. Because speckle can make it harder to distinguish soft tissue differences, modern ultrasound mac...
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Beam width artifact

Ultrasound beam width artifact occurs when a reflective object located beyond the widened ultrasound beam, after the focal zone, creates false detectable echoes that are displayed as overlapping the structure of interest. Features To understand this artifact, it is important to remember that t...
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Modified PIOPED II criteria for diagnosis of pulmonary embolus

The modified PIOPED II criteria for the diagnosis of pulmonary embolus indicate the presence or absence of pulmonary emboli based on findings on V/Q scan (ventilation-perfusion scintigraphy). The following article reflects the modified interpretation criteria promulgated in 2008 1 based on recat...
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Superior vena cava obstruction

Superior vena cava obstruction (SVCO) can occur from extrinsic compression, intrinsic stenosis, or thrombosis of the superior vena cava. Malignancies are the main cause and are considered an oncologic emergency. Superior vena cava syndrome (SVCS) refers to the clinical syndrome with symptoms tha...
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Little league shoulder

Little league shoulder is thought to occur due to overuse damage of the proximal humeral epiphysis/metaphysis, seen typically in young baseball players, especially pitchers. Epidemiology Although it is most commonly seen in baseball players particularly in pitchers, it also presents in adolesc...
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Garden classification of subcapital femoral neck fractures

The Garden classification of subcapital femoral neck fractures describes femoral neck fracture displacement and aims to assist in clinical decision-making to reduce the rates of non-union and osteonecrosis 1,2,4. Usage The Garden classification is the most commonly used system (c.2018) despit...
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Galassi classification of middle cranial fossa arachnoid cysts

The Galassi classification of middle cranial fossa arachnoid cysts is used to classify arachnoid cysts in the middle cranial fossa, which account for 50-60% of all arachnoid cysts 1.  Usage Galassi et al. published this classification in 1982, and at the time of writing (June 2016), it remains...
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Full-thickness rotator cuff tear

Full-thickness rotator cuff tears extend from the bursal surface to the articular surface. They are less common than partial-thickness tears 5. Epidemiology Full-thickness tears are common. Their reported prevalence increases with age and ranges from 5% to 17% 5. Clinical presentation Clini...
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Autosomal dominant polycystic kidney disease

Autosomal dominant polycystic kidney disease (ADPKD), also sometimes referred to as "adult polycystic kidney disease", is an inherited form of adult cystic renal disease.  Epidemiology Autosomal dominant polycystic kidney disease is one of the most common serious hereditary diseases, found in ...
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Localized cystic renal disease

Localized cystic renal disease (LCRD), also known as localized cystic kidney disease, is an uncommon, non-familial, non-progressive disease characterized by clusters of cysts seperated by otherwise normal renal parenchyma. It can be confused with unilateral autosomal dominant polycystic kidney d...
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Frykman classification of distal radial fractures

The Frykman classification of distal radial fractures is based on the AP appearance and encompasses the eponymous entities of Colles fracture, Smith fracture, Barton fracture, chauffeur fracture. It assesses the pattern of fractures, involvement of the radioulnar joint and presence of a distal u...
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Focal hepatic hot spot sign

The focal hepatic hot spot sign, also known as the hot quadrate sign can be seen on technetium 99m sulfur colloid scans of the liver and spleen, as well as CT studies. Radiographic features It occurs as a focal area of increased radiopharmaceutical uptake, or iodinated contrast accumulation, i...
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Renal papillary necrosis (mnemonic)

Mnemonics for the causes of renal papillary necrosis are plentiful and include: NSAID POSTCARDS AD SPORT C: a list of causes in decreasing order of incidence DINASOR Mnemonics NSAID Most common causes: N: non-steroidal anti-inflammatory drugs (NSAIDs) S: sickle cell disease A: acetamin...
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Medullary nephrocalcinosis (mnemonic)

A mnemonic used to remember the etiology of medullary nephrocalcinosis is: HAM HOP Mnemonic H: hyperparathyroidism A: (renal tubular) acidosis M: medullary sponge kidney/ milk-alkali syndrome H: hypercalcemia/hypercalciuria O: oxalosis P: papillary necrosis See also cortical nephrocal...
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Cortical nephrocalcinosis (mnemonic)

Mnemonics for common causes of cortical nephrocalcinosis are: COAG GOAT Mnemonics COAG C: cortical necrosis O: oxalosis A: Alport syndrome G: glomerulonephritis (chronic) GOAT G: glomerulonephritis (chronic) O: oxalosis A: Alport syndrome/ acute cortical necrosis T: transplant rejec...
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Meconium plug syndrome

Meconium plug syndrome refers to a functional colonic obstruction in a newborn due to an obstructing meconium plug. It is usually transient and affects the left colon with meconium plugging the bowel distal to this segment. It is also known as small left colon syndrome or functional immaturity o...
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Asterion

The asterion is the junction on the side of the posteroinferior calvarium where three sutures meet: parietomastoid suture occipitomastoid suture lambdoid suture It represents the site of the closed mastoid fontanelle. It is located at the posterior end of the parietotemporal suture, whereas ...
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Physiologic periostitis

Physiologic periostitis describes the normal presence of smooth bilateral diaphyseal periosteal new bone formation along the humeri, femora, or tibiae of infants aged 1 to 6 months. It can be observed in both preterm and term infants. The etiology is unclear but may simply relate to rapid growth...
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Pleomorphic liposarcoma

Pleomorphic liposarcomas are high-grade malignant neoplasms arising from adipocytic tissues characterized by a variable number of pleomorphic lipoblasts and the absence of areas of well-differentiated liposarcoma and other lines of differentiation. Epidemiology Pleomorphic sarcomas are rare an...
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Prune belly syndrome

Prune belly syndrome, also known as Eagle Barrett syndrome 3 or triad syndrome, is a rare anomaly comprising a specific constellation of features. It consists of three major findings: gross pelvicalyceal and ureteric dilatation with renal dysplasia 7 anterior abdominal wall underdevelopment (r...

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