Articles

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16,918 results
Article

Gallbladder

The gallbladder is a pear-shaped musculomembranous sac located along the undersurface of the liver. It functions to accumulate and concentrate bile between meals. Gross anatomy The normal adult gallbladder measures from 7-10 cm in length and 3-4 cm in transverse diameter 6. It communicates wit...
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Perivertebral space

The perivertebral space is one of the deep compartments of the head and neck and includes the prevertebral space and paraspinal space. Gross anatomy The perivertebral space is a cylinder of soft tissue lying posterior to the retropharyngeal space and danger space surrounded by the prevertebral...
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Calcific tendinitis of the longus colli muscle

Calcific tendinitis of the longus colli muscles is an inflammatory/granulomatous response to the deposition of calcium hydroxyapatite crystals in the tendons of the longus colli muscle. It is sometimes more generically known as calcific prevertebral tendinitis or, less accurately, as retropharyn...
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Pleural effusion

Pleural effusions are abnormal accumulations of fluid within the pleural space. They may result from a variety of pathological processes which overwhelm the pleura's ability to reabsorb fluid. Terminology "Pleural effusion" is commonly used as a catch-all term to describe any abnormal accumula...
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Yellow nail syndrome

Yellow nail syndrome is a rare disorder principally affecting the lymphatic system. Epidemiology It is a rare disease with an approximate incidence of less than one million/year 8. There may be a slightly increased female predilection 5. While clinical onset varies from birth to late adult lif...
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Chylothorax

A chylothorax (plural: chylothoraces), also known as chylopleura, chylous hydrothorax or chylous pleurisy 13, refers to the presence of chylous fluid in the pleural space often as a result of obstruction or disruption to the thoracic duct. It may be congenital or acquired. Epidemiology Associa...
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Intestinal lymphangiectasia

Intestinal lymphangiectasia is a condition characterized by dilated intestinal lacteals causing loss of lymph into the lumen of the small intestine. This can result in hypoproteinemia, hypogammaglobulinemia, hypoalbuminemia and lymphopenia.  Epidemiology It may present in either children or ad...
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Stomach

The stomach is a muscular organ that lies between the esophagus and duodenum in the upper abdomen. It lies on the left side of the abdominal cavity caudal to the diaphragm at the level of T10. Gross anatomy The stomach ("normal" empty volume 45 mL) is divided into distinct regions: cardia: th...
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OK sign test

The OK sign test is a clinical test to evaluate for potential injury of the anterior interosseous nerve. Gross anatomy The anterior interosseous nerve (roots C8-T1) is a branch off the median nerve (roots C6-T1), arising just after the median nerve passes through the two heads of the pronator ...
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Caudothalamic groove

The caudothalamic groove is an important landmark when performing neonatal cranial ultrasound. Gross anatomy As the name suggests, it is located between the caudate nucleus and thalamus and is a shallow groove projecting from the floor of the lateral ventricle. It is approximately at the level...
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Frontal lobe

The frontal lobe is by far the largest of the four lobes of the cerebrum (other lobes: parietal lobe, temporal lobe, and occipital lobe), and is responsible for many of the functions which produce voluntary and purposeful action. Gross anatomy The frontal lobe is the largest lobe accounting fo...
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Cerebral microhemorrhage

Cerebral microhemorrhages, or cerebral microbleeds, are small focal intracerebral hemorrhages, often only visible on susceptibility-sensitive MRI sequences. Pathology Common etiologies cardiac bypass for surgery 15,31 cavernous malformations 1,8 especially Zabramski classification type IV m...
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Hepatic encephalopathy

Hepatic encephalopathy, also known as acute hyperammonemic encephalopathy or portosystemic encephalopathy, refers to a spectrum of neuropsychiatric abnormalities occurring in patients with liver dysfunction and portal hypertension. It results from exposure of the brain to excessive amounts of am...
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Multiple system atrophy cerebellar type (MSA-C)

Multiple system atrophy cerebellar type (MSA-C), previously known as olivopontocerebellar degeneration, is a neurodegenerative disease, and one of the clinical phenotypes of multiple systemic atrophy (MSA). Terminology The prevailing thought is that that olivopontocerebellar degeneration, Shy-...
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Mature cystic ovarian teratoma

Ovarian dermoid cyst and mature cystic ovarian teratoma are terms often used interchangeably to refer to the most common ovarian neoplasm. These slow-growing tumors contain elements from multiple germ cell layers and can be assessed with ultrasound or MRI.  Terminology Although they have very ...
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Floating balls sign

The floating balls sign refers to the appearance of multiple mobile globules/spherules of solid, usually fatty, tissue within an adnexal cyst. It is pathognomonic for ovarian mature cystic teratoma 1,2.  Terminology Alternative names include the meatballs 3, truffle sign 4, and boba sign 13. ...
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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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Gastropericardial fistula

Gastropericardial fistulas are rare abnormal communications between the stomach and the pericardial sac. This is a life-threatening condition that can lead to impaired cardiac function, sepsis and eventually death. Clinical presentation Patients with gastropericardial fistula may present with ...
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Gibbus deformity

A gibbus deformity is a short-segment structural thoracolumbar kyphosis resulting in sharp angulation. Pathology Etiology There are a number of causes which can be divided into congenital and acquired. Congenital achondroplasia cretinism (congenital hypothyroidism) Apert syndrome Coffin-...
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Scoliosis

Scoliosis (plural: scolioses) is defined as an abnormal lateral curvature of the spine. It is quite common in young individuals and is often idiopathic and asymptomatic. In some cases, however, it is the result of underlying structural or neurological abnormalities. Terminology Early onset sco...

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