Articles

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More than 200 results
Article

Marginal cord insertion

Marginal cord insertion, also known as a 'battledore insertion', is a type of abnormal cord insertion. Terminology Insertion of the umbilical cord within <2 cm from the placental margin is described as marginal cord insertion (usually defined as <2 cm 5, although some references define it as <...
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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.  Terminology Historically, MSA was divided into one of three clinical patterns, i...
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Scrotum

The scrotum (plural: scrota or scrotums) is a dual-chambered protuberance of skin and muscle that contains the testes, epididymides, and spermatic cord. It consists of two chambers separated by a septum. It is an extension of the perineum and is located between the penis and anus. Gross anatomy...
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Testes

The testes (singular: testis), also known as the testicles, are the male gonads and are contained within the scrotum. The testes are responsible for the production of sperm and testosterone. Terminology The term testis (plural testes) is preferred by the Terminologia Anatomica, over testicle. ...
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Epididymis

The epididymis (plural: epididymides) is situated adjacent to the testis within the scrotal sac. Its primary function is the collection, maturation and transport of sperm via the ductus deferens. Gross anatomy The epididymis is an elongated structure, posterolateral to the testis. It can be su...
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Shy-Drager syndrome (historical)

The Shy-Drager syndrome is now recognized as a clinical manifestation of multiple systemic atrophy, no longer considered a separate entity. Clinical presentation The most striking clinical finding in Shy-Drager syndrome is arterial orthostatic hypotension. This remains a core clinical feature...
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Obsolete imaging techniques

It is almost axiomatic that as time passes, the imaging techniques by which patients are evaluated, eventually become obsolete, due to continued scientific and technological innovations.  Although the reality of new-fangled technology coming along and supplanting established methodology is of c...
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Meconium pseudocyst

Meconium pseudocyst forms in response to meconium peritonitis, isolating the meconium from the rest of the peritoneum into one or several cystic lesions. Pathology It occurs when the extruded meconium becomes walled off within the peritoneal space. Radiographic features Plain radiograph App...
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Page kidney

Page kidney, or Page phenomenon, refers to systemic hypertension secondary to extrinsic compression of the kidney by a subcapsular collection, e.g. hematoma, seroma, or urinoma. Clinical presentation Patients present with hypertension, which may be recognized acutely after an inciting event or...
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Thyroid nodule

Thyroid nodules are any discrete lesion that can be delineated on imaging studies from the adjacent thyroid parenchyma. They can represent a range of benign or malignant conditions. Epidemiology They are more common in females (4:1 F:M) and have an increasing prevalence with increasing age and...
Article

Adenomyomatosis of the gallbladder

Adenomyomatosis of the gallbladder is a hyperplastic cholecystosis of the gallbladder wall. It is a relatively common and benign cause of diffuse or focal gallbladder wall thickening, most easily seen on ultrasound and MRI.  Epidemiology Adenomyomatosis is relatively common, found in ~9% of al...
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Perugini grading scale

The Perugini grading scale is a semi-quantitative method of scoring cardiac uptake following injection of 99mTc-DPD, 99mTc-Pyrophosphate or 99mTc-HMDP scintigraphy in the investigation of cardiac amyloidosis (particularly ATTR amyloidosis). The grading scale visually compares tracer uptake in th...
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Cardiac amyloidosis

Cardiac amyloidosis (plural: amyloidoses) is a significant source of morbidity among patients with systemic amyloidosis and is the most common cause of restrictive cardiomyopathy outside the tropics. Pathology Amyloidosis represents the extracellular deposition of insoluble fibrillar proteinac...
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Transthyretin amyloidosis

Transthyretin (ATTR) amyloidosis is a form of systemic amyloidosis characterized by the misfolding, aggregation and deposition of transthyretin-related (TTR) protein in various organs 1-6. This can occur in the following two forms namely in the setting of a genetically normal transthyretin-relat...
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Late gadolinium enhancement

Late gadolinium enhancement is a technique used in cardiac MRI for cardiac tissue characterization, in particular, the assessment of myocardial scar formation and regional myocardial fibrosis 1-5. Terminology Late gadolinium enhancement is also known under the terms ‘late enhancement’ or ‘dela...
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T1 mapping - myocardium

T1 mapping is a magnetic resonance imaging technique used to calculate the T1 time of a certain tissue and display them voxel-vice on a parametric map. It has been used for myocardial tissue characterization 1-6 and has been investigated for other tissues 5. Terminology Native T1 is referred t...
Article

Alphabet inspired signs

There are many alphabet-inspired signs in radiology: A line (US artifact) C sign (MSK) D sign (cardiac) delta sign delta sign (brain) double delta sign (MSK) empty delta sign (brain) E sign G sign (gout) gamma sign (bicornuate uterus) H-shaped vertebrae H sign H sign (sacrum) H sig...
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Arytenoid cartilage

The arytenoid cartilages are paired hyaline cartilages that articulate with the sloping upper border of the lamina of the cricoid cartilage via the synovial cricoarytenoid joint. This joint allows movement of the arytenoid cartilages, which is vital in approximating, tensing and relaxing the voc...
Article

Rectum

The rectum is the last part of the large intestine. It is located within the pelvis and is the continuation of the sigmoid colon after the rectosigmoid junction and continues as the anal canal at the anorectal angle created by puborectalis.  Gross anatomy At the level of the S3 vertebral body,...
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Sigmoid colon

The sigmoid colon is the continuation of the descending colon. Gross anatomy After the distal descending colon has curved medially it enters the pelvis, where it gains a mesentery and is then called the sigmoid colon. It measures approximately 15 cm in length.  It has a "S" (Greek letter sigm...

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