Articles
Articles are a collaborative effort to provide a single canonical page on all topics relevant to the practice of radiology. As such, articles are written and continuously improved upon by countless contributing members. Our dedicated editors oversee each edit for accuracy and style. Find out more about articles.
3,363 results found
Article
Spiral glenohumeral ligament
The spiral glenohumeral ligament, also termed fasciculus obliquus, ligamentum glenohumerale spirale and spiral GHL, is a focal thickening of the glenohumeral joint capsule, akin to the other glenohumeral ligaments, yet it is not widely recognized 1.
Gross anatomy
The spiral glenohumeral ligam...
Article
Appendix
The appendix or vermiform appendix (plural: appendices) is a blind muscular tube arising from the cecum, the first part of the large bowel.
Gross anatomy
The appendix arises from the posteromedial surface of the cecum, approximately 2-3 cm inferior to the ileocecal valve, where the three longi...
Article
Bovine arch
Bovine arch is the most common variant of the aortic arch and occurs when the brachiocephalic (innominate) artery shares a common origin with the left common carotid artery.
Epidemiology
A bovine arch is present in ~15% (range 8-27%) of the population and is more common in individuals of Afri...
Article
Posterior tibial artery
The posterior tibial artery (PTA) is one of the 2 branches of the tibioperoneal trunk in the lower leg and provides oxygenated blood to the posterior compartments of the leg and plantar surface of the foot. It is accompanied by the posterior tibial vein, along its course.
Summary
origin: tibio...
Article
Persistent hypophyseal canal
Persistent hypophyseal canal, also known as the craniopharyngeal canal when larger than 1.5 mm in diameter, is a rare congenital defect characterized by communication through the central skull base between the nasopharynx and the pituitary fossa.
Terminology
There are a number of terms that r...
Article
Lumbosacral trunk
The lumbosacral trunk is the distal trunk of the lumbar plexus arising from the anterior rami of the L4 and L5 nerve roots which contributes to the sacral plexus.
Gross anatomy
Origin
It arises from anterior rami of L4-L5 roots of the lumbar plexus.
Course
emerges over the medial border of ...
Article
Infrahyoid muscles
The infrahyoid muscles or strap muscles are a group of four paired muscles in the anterior neck below the hyoid bone, within the muscular triangle. They are responsible for depressing the hyoid during swallowing. These muscles can be remembered by the mnemonic "TOSS".
They can be difficult to d...
Article
Pontine arteries
The pontine branches are the small arterial branches of the basilar artery that supply the pons and structures adjacent to the pons.
There are usually 3-5 paired arterial branches which are located in the mid-basilar region between the anterior inferior cerebellar artery and the superior cerebe...
Article
Wilbrand knee (optic radiation)
The Wilbrand knee refers to a small anterior loop of axons from the medial retina passing a short distance into the contralateral prechiasmatic optic nerve after decussating in the optic chiasm. It is said to account for the occurrence of the junctional scotoma caused by lesions at the junction ...
Article
Ligamentum teres of the hip
The ligamentum teres, also known as the ligamentum capitis femoris or round ligament of the hip, is an intra-articular ligament within the medial hip joint.
Gross anatomy
The ligament passes from the transverse ligament and acetabular notch of the acetabulum to the femoral head where it insert...
Article
Agger nasi cells
Agger nasi air cells are the most anterior ethmoidal air cells lying anterolateral and inferior to the frontal recess and anterior and above the attachment of the middle turbinate. They are located within the lacrimal bone and therefore have as lateral relations the orbit, the lacrimal sac and t...
Article
Autonomic nervous system
The autonomic nervous system (ANS) is a subdivision of the peripheral nervous system. The autonomic system provides innervation of the involuntary muscles, i.e. myocardium and smooth muscle, and glands, through which fine control of homeostasis is maintained.
The afferent innervation of the aut...
Article
Parasympathetic nervous system
The parasympathetic nervous system (PaNS/PNS), mediated by the head and neck ganglia and pelvic splanchnic nerves, is a major division of the autonomic nervous system. It is composed of general visceral afferent and efferent axons that allow for involuntary control of bodily functions via severa...
Article
Sympathetic nervous system
The sympathetic nervous system (SNS), mediated by the sympathetic chain (trunk) and ganglia, is a major division of the autonomic nervous system. It is composed of general visceral afferent and efferent axons that allow for involuntary control of bodily functions via the hypothalamus.
The over...
Article
Circumcaval ureter
Circumcaval ureter, also known as retrocaval ureter, is a term used to describe an abnormal course of a ureter that encircles the inferior vena cava. Both of these terms are somewhat misleading, as this configuration is considered a developmental anomaly of the inferior vena cava (IVC).
Clinic...
Article
Persistent primitive trigeminal artery
Persistent primitive trigeminal artery (PPTA) is the most common type of the four persistent carotid-vertebrobasilar anastomoses. It is present in 0.1-0.6% of cerebral angiograms and is usually unilateral.
In utero, the trigeminal artery supplies the basilar artery before the development of the...
Article
Butterfly vertebra
Butterfly vertebra, also sometimes known as a sagittal cleft vertebra or anterior rachischisis, is a type of vertebral anomaly that results from the failure of fusion of the lateral halves of the vertebral body because of persistent notochordal tissue between them.
Pathology
Butterfly vertebra...
Article
Infratemporal fossa
The infratemporal fossa is a complex space of the face that lies posterolateral to the maxillary sinus, below the skull base, and between the pharyngeal sidewall and mandibular ramus. It overlaps with the masticator space and prestyloid parapharyngeal space.
Gross anatomy
The infratemporal fos...
Article
Occipital vertebra
Occipital vertebrae are rare anatomical variants that result from incomplete or aberrant fusion of occipital bone ossification centers. There is a broad spectrum of occipital vertebrae, the more common variants include:
third condyle (condylus tertius)
basilar process
prebasioccipital arch
p...
Article
Posterior ciliary arteries
The posterior ciliary arteries are usually paired branches arising from the ophthalmic artery, one medial and one lateral, each giving off a number of branches that supply the uvea 1.
Close to the optic nerve, are the short posterior ciliary arteries, usually numbering 16-20; these supply the p...