Articles

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16,873 results found
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Lambda sign (disambiguation)

There are two described lambda (λ) signs: lambda sign (twin pregnancy) lambda sign (sarcoidosis)
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Posterior right subhepatic space

The posterior right subhepatic space (also known as the hepatorenal fossa or Morison pouch) separates the liver from the right kidney. It is a potential space that is not filled with any fluid in normal conditions. Gross anatomy The posterior right subhepatic space is a subcompartment of the s...
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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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Bird beak sign (disambiguation)

Bird beak sign is used in many contexts to denote a rapid tapering to a point, reminiscent of a bird's beak. Described bird beak signs include:  baby bird's beak sign (fetal TGA) beak sign (arterial dissection) beak sign (gallbladder) beak sign (ovary) beak sign (pyloric stenosis) bird bea...
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Baby bird's beak sign

The baby bird's beak sign is an antenatal ultrasound appearance formed by the pulmonary artery abnormally arising from the left ventricle in fetuses with transposition of the great arteries 1-3. In these cases, the pulmonary artery bifurcation and abnormal outflow tracts mimic the head of a bab...
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Generative adversarial network

Generative adversarial networks (GANs) are an elegant deep learning approach to generating artificial data that is indistinguishable from real data. Two neural networks are paired off against one another (adversaries). The first network generates artificial data to reproduce real data. The secon...
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Proximal radio-ulnar synostosis

Proximal radio-ulnar synostosis is an upper limb skeletal malformation characterized by bony fusion at the proximal aspect of the radius and ulna. Of the radio-ulnar synostoses, the proximal third is considered the most common site.  Epidemiology Proximal radioulnar synostoses are rare occurre...
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Red and yellow flags for guiding imaging of lower back pain

Lower back pain (also known as lumbago) is very common and is often referred for imaging. However, the vast majority of cases are due to benign self-limiting causes which do not require imaging and resolve with conservative measures. Numerous authors have described various methods for supporting...
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Endovascular arteriovenous fistula creation

Endovascular arteriovenous fistula creation is a minimally invasive alternative for the creation of arteriovenous fistulae for haemodialysis access. Technique Catheter-based technology and image guidance in the form of ultrasound and fluoroscopy is utilized create a side-to-side anastomosis be...
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Fetal tricuspid regurgitation

Tricuspid regurgitation (TR) (also known as tricuspid insufficiency) is a common finding in imaging of the fetus. Tricuspid regurgitation represents the abnormal backflow of blood into the right atrium during right ventricular contraction due to valvular leakage (i.e. it is a valvulopathy).  Ep...
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Temporal bone

The temporal bone is situated on the sides and the base of the cranium and lateral to the temporal lobe of the cerebrum. The temporal bone is one of the most important calvarial and skull base bones.  Gross anatomy The temporal bone is divided into several main parts/portions 1-3: squamous pa...
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Thyroid-associated orbitopathy

Thyroid-associated orbitopathy, also known as thyroid-associated ophthalmopathy or thyroid eye disease, is the most common cause of proptosis in adults and is most frequently associated with Graves disease. On imaging, it is characterized by bilateral and symmetrical enlargement of the extraocul...
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Zygoma

The zygoma (also known as zygomatic bone or malar bone) is an important facial bone which forms the prominence of the cheek. It is roughly quadrangular in shape. Gross anatomy Zygoma has three surfaces, five borders, and two processes. Surfaces anterolateral surface is convex, pierced at its...
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Vomer

The vomer is one of the unpaired facial bones and forms the posteroinferior part of the bony nasal septum, lying in the midline between the two nasal cavities. It is a thin flat bone that is trapezoidal in shape with two surfaces that are obliquely grooved by the sphenopalatine (nasopalatine) v...
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Sphenoid bone

The sphenoid bone is a large, complex, unpaired bone forming the central parts of the anterior and central skull base. Gross anatomy Parts of the sphenoid bone include: body jugum sphenoideum contains the sphenoid sinus greater wing lesser wing pterygoid process and plates Articulations...
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Multiple system atrophy

Multiple system atrophy (MSA) is a sporadic neurodegenerative disease and synucleinopathy characterized by varying degrees of cerebellar ataxia, autonomic dysfunction, parkinsonism, and corticospinal dysfunction.  Epidemiology Multiple systemic atrophy is a sporadic disease, with a prevalence ...
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Parietal bone

The parietal bone is a paired, irregular, quadrilateral skull bone that forms the sides and roof of the cranium.  Gross anatomy The parietal bone has four borders, four angles, and external/internal surfaces. The four borders are: frontal sagittal occipital (half of lambdoid suture) squam...
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Distal humeral fracture

Distal humeral fractures are traumatic injuries involving the epicondyles, the trochlea, the capitellum, and the metaphysis of the distal humerus. They are often the result of high-energy trauma, such as road traffic accidents or a fall from a height. In the elderly, they may occur as a domestic...
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Skull

The skull (TA: cranium) is the superior-most part of the human skeleton and houses the brain and includes the skeletal elements of the face. It consists of numerous bones connected to each other by sutures which renders them immobile. Terminology Variability in which bones to include and how t...
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Palatine bone

The palatine bones are paired L-shaped bones joined at the midline. They form the hard palate with the maxillary bones. They also form part of the floor of the nasal cavity (the hard palate separates the oral cavity from the nasal cavity).  Gross anatomy The palatine bones are located at the b...

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