Articles

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16,791 results found
Article

Intrinsic muscles of the larynx

The intrinsic muscles of the larynx can be considered in two groups: muscles that control the inlet of the larynx muscles that move the vocal ligaments Gross anatomy Muscles of the inlet aryepiglottic muscle: lies within the aryepiglottic fold, runs from the side of the epiglottis and inser...
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False vocal cords

The false vocal cords (vestibular folds, ventricular folds, ventricular bands) are paired shelf-like structures located within the supraglottic larynx that divide the laryngeal vestibule above from the laryngeal ventricle below. They function to protect the airway and play very little if any par...
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Rima vestibuli

The rima vestibuli is the V-shaped space formed between the false vocal cords, which allows the passage of air through the larynx. It is larger and located superior to the rima glottidis. It should not be confused for the laryngeal vestibule, which is the entire open space of the supraglottis b...
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Rima glottidis

The rima glottidis is the V-shaped opening formed between the true vocal cords, which permits the passage of air through the larynx. Abduction or adduction of the vocal cords can open or close the rima glottidis. The rima glottidis constitutes part of the glottic region of the larynx. It should...
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Fetal posterior cerebral artery

A fetal (origin of the) posterior cerebral artery is a common variant in the posterior cerebral circulation, estimated to occur in 20-30% of individuals 2. A fetal posterior communicating artery (PCom) describes a situation whereby the PCom is larger than the P1 segment of the posterior cerebra...
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Parapharyngeal space

The parapharyngeal space (PPS), also known as the prestyloid parapharyngeal space, is a deep compartment of the head and neck around which most other suprahyoid fascial spaces are arranged. It consists largely of fat, neurovascular structures, and, in some definitions, the retromandibular part o...
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Sacral nerve stimulator

Sacral nerve stimulators (SNS) are a form of neuromodulation therapy. They are used for urogenital disorders such as urge urinary incontinence and detrusor hyperactivity, and colorectal disorders such as chronic constipation refractory to conventional medical therapy, and fecal incontinence. The...
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Vagal nerve stimulator

Vagal nerve stimulators, or vagus nerve stimulators (VNS), are implantable devices used to treat a number of conditions, although the mechanism of action has not been completely elucidated. Indications Vagal nerve stimulators are indicated in patients with 1-3: drug-refractory epilepsy e.g. ...
Article

Medical abbreviations and acronyms (S)

This article contains a list of commonly used medical abbreviations and acronyms that start with the letter S and may be encountered in medicine and radiology (please keep the main list and any sublists in alphabetic order). A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R ...
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Gallbladder agenesis

Agenesis of the gallbladder describes the rare congenital absence of the gallbladder. Epidemiology overall incidence is estimated at <0.1% (range 0.04-0.1%) gender:  reported 3:1 female predominance of symptomatic cases equivalent gender distribution in autopsy cases Associations Gallblad...
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Testicular descent

Testicular descent occurs after the fourth month of fetal life. The testes are derived from the gonadal ridge medial to the mesonephric ridge of the intermediate cell mass.  The gubernaculum, a fibrous structure connecting the gonad to the inguinoscrotal fold, shortens which migrates the gonad ...
Article

Testis

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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Prostate

The prostate gland is the largest accessory gland of the male reproductive system. It typically weighs between 20-40 grams with an average size of 3 x 4 x 2 cm. The prostate is comprised of 70% glandular tissue and 30% fibromuscular or stromal tissue 1-3 and provides ~30% of the volume of semina...
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Vallecula

The epiglottic valleculae are paired small depressions in the oropharynx located either side of the median glossoepiglottic fold, anterior to the epiglottis and posterior to the base of tongue.  They are bounded laterally by the lateral glossoepiglottic folds. It has a function in the pharyngeal...
Article

Groin herniation

Groin hernias (herniae also used) may be congenital or acquired, and represent a large proportion of all abdominal wall hernias. The subtypes based on location are: inguinal hernia (involving the inguinal canal) direct inguinal hernia indirect inguinal hernia: five times commoner than direct...
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Inguinal hernia

Inguinal hernias (herniae also used) is the type of groin herniation (part of the larger group of abdominal wall hernias) that occurs above the inguinal ligament and through the inguinal canal. Epidemiology Inguinal hernias are the commonest type of abdominal wall hernias (up to 80% 3) and are...
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Direct inguinal hernia

A direct inguinal hernia (alternative plural: herniae) is a type of groin herniation, that arises from protrusion of abdominal viscera through a weakness of the posterior wall of the inguinal canal medial to the inferior epigastric vessels, specifically through Hesselbach's triangle. This type ...
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Indirect inguinal hernia

Indirect inguinal hernias (alternative plural: herniae), a type of groin herniation, are the most common type of abdominal hernia. Epidemiology It is five times more common than a direct inguinal hernia, and is seven times more frequent in males, due to the persistence of the processus vaginal...
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Non-medical drug use (radiological manifestations)

Radiological manifestations of non-medical drug use are commonly seen as the non-medical use of drugs is widespread. Epidemiology Interestingly, 2013 reports have suggested a decreasing incidence of reported drug use in the general population over the past decade, but it remains that ~36% of t...
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Ependymal dot-dash sign

The ependymal dot-dash sign has been described as an early MRI imaging feature of multiple sclerosis before other more florid white matter changes (e.g. Dawson's fingers) become evident 1. It has also been suggested as a feature that can be used to distinguish multiple sclerosis from neuromyelit...

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