Articles
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16,918 results
Article
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...
Article
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...
Article
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...
Article
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...
Article
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...
Article
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...
Article
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 ...
Article
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...
Article
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...
Article
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...
Article
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-...
Article
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 ...
Article
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.
...
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,...
Article
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 ...
Article
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-...
Article
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...
Article
Whirlpool sign (testicular torsion)
The whirlpool sign of the spermatic cord is a direct sign of testicular torsion, both complete and incomplete (i.e. <360°). It is considered to be the most specific and sensitive sign for testicular torsion.
Terminology
The term whirlpool sign is used in other contexts: see whirlpool sign (dis...
Article
Testicular torsion
Testicular torsion occurs when a testis torts on the spermatic cord resulting in the cutting off of blood supply. The most common symptom is acute testicular pain and the most common underlying cause, a bell-clapper deformity. The diagnosis is often made clinically but if it is in doubt, an ultr...
Article
Tarlov cyst
Tarlov cysts, also called perineural cysts, are CSF-filled dilatations of the nerve root sheath at the dorsal root ganglion (posterior nerve root sheath). These are type II spinal meningeal cysts that are, by definition, extradural but contain neural tissue.
Most Tarlov cysts are asymptomatic, ...