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.
More than 200 results
Article
Top of the basilar syndrome
Top of the basilar syndrome, also known as rostral brainstem infarction, occurs when there is thromboembolic occlusion of the top of the basilar artery. This results in bilateral thalamic ischemia due to occlusion of perforator vessels.
Clinical presentation
Clinically, top of the basilar synd...
Article
Facial artery
The facial artery is one of the external carotid artery branches and supplies blood to the structures of the face.
Summary
origin: branch of the external carotid artery a little above the level of the lingual artery, in the carotid triangle of the neck
course: passes deep to the posterior bel...
Article
Right hepatic artery
The right hepatic artery (RHA) is formed when the proper hepatic artery (PHA) bifurcates. The hepatic arteries provide 25% of the blood supply and 50% of the oxygen supply to the liver.
Gross anatomy
The proper hepatic artery bifurcates into the right and left hepatic arteries at or before rea...
Article
Congenital absence of the internal carotid artery
Congenital absence of the internal carotid artery (ICA) is a rare anomaly that occurs in less than 0.01% of the population. It encompasses agenesis, aplasia, and hypoplasia 1.
The most common type of collateral flow is through the circle of Willis, through the anterior communicating artery (ACo...
Article
Angular artery (facial artery branch)
The angular artery is the terminal branch of the facial artery.
It becomes the angular artery after the lateral nasal artery branch from the facial artery. It courses superiorly along the lateral border of the external nose to the medial canthus. It is accompanied by the angular vein, which dra...
Article
Left anterior descending artery
The left anterior descending (LAD) artery, also known as the anterior interventricular branch, is one of the two branches of the left coronary artery (the other branch being the circumflex (Cx) artery).
Terminology
The left anterior descending artery is often given the sobriquet, the widow-mak...
Article
Angular vein
The angular vein drains the anterior region of the scalp 1. It is formed by the union of the supratrochlear and supraorbital veins and becomes the facial vein 1,2,3.
Gross anatomy
The angular vein forms at the medial canthus as the supratrochlear and supraorbital veins unite 1,2. The angular v...
Article
Abdominal and pelvic anatomy
Abdominal and pelvic anatomy encompasses the anatomy of all structures of the abdominal and pelvic cavities.
This anatomy section promotes the use of the Terminologia Anatomica, the international standard of anatomical nomenclature.
Article
Williams syndrome
Williams syndrome (WS), sometimes called Williams-Beuren syndrome, is characterized by some or all of the following features:
craniofacial dysmorphism (e.g. elfin facies)
oral abnormalities
short stature (50% of cases)
mild to moderate intellectual disability
supravalvular aortic stenosis ...
Article
Telangiectasias
A telangiectasia commonly refers to a group of abnormally prominent capillaries that occur close to a mucosal surface. Rarely they are also referred to denote vascular malformations at other non-mucosal sites (e.g. capillary telangiectasias of the brain) 1.
Associations
There are numerous cond...
Article
Crescent sign of arterial dissection
The crescent sign refers to the high signal crescent seen in the wall of a vessel when dissected. This may be seen both on T1 or T2 sequences depending on the age of the blood (see aging blood on MRI). It is classically referred to in internal carotid artery dissection.
It should not be confuse...
Article
Calcarine artery
The calcarine artery, named according to its course in the calcarine fissure, is a branch of the posterior cerebral artery, usually from the P3 segment. It may also arise from the parieto-occipital artery or posterior temporal branches. It courses deep in the fissure, giving branches both to the...
Article
Persistent proatlantal intersegmental artery
The proatlantal intersegmental artery is also known as the type I proatlantal artery, and is one of the persistent carotid-vertebrobasilar anastomoses. It arises from the internal carotid artery (similar to the persistent hypoglossal artery) but instead of heading for the hypoglossal canal, it j...
Article
Acute abdominal pain
Acute abdominal pain is a common acute presentation in clinical practice. It encompasses a very broad range of possible etiologies and diagnoses, and imaging is routinely employed as the primary investigative tool in its modern management.
Terminology
A subgroup of patients with acute abdomina...
Article
Acquired aortic conditions
Acquired aortic conditions include:
aortic dissection
aortic rupture/transection
ascending aortic aneurysm
aortitis
thoracic aortic injury
abdominal aortic aneurysm
inflammatory abdominal aortic aneurysm
Article
Ovarian vein thrombosis
Ovarian vein thrombosis (actually most often thrombophlebitis) occurs most commonly in postpartum patients and can result in pulmonary emboli. A presentation is usually with acute pelvic pain in the postpartum period, then termed puerperal ovarian vein thrombosis or postpartum ovarian vein throm...
Article
Tulip bulb sign
The tulip bulb sign refers to the characteristic appearance of annuloaortic ectasia as seen on CT angiography.
There is symmetric dilatation of the three sinuses of Valsalva, with extension into the ascending aorta and effacement of the sinotubular junction.
It is seen especially in Marfan sy...
Article
Inferior rectal artery
The inferior rectal artery arises from the internal pudendal artery and supplies the lower anal canal including the external anal sphincter.
Summary
origin: from internal pudendal artery, just after it enters the pudendal canal
course: runs anteromedially through the ischioanal fossa to reach...
Article
Pulmonary artery pseudoaneurysm
Pulmonary artery pseudoaneurysm refers to a pseudoaneurysm arising from the pulmonary arteries.
Pathology
A pseudoaneurysm results from a tear or disruption of all three layers of the vessel wall. Extravasated blood is contained by compressed extravascular tissue or a clot, which makes up the ...
Article
Arteriosclerosis
Arteriosclerosis is defined by thickening and loss of elasticity of the arterial walls.
There are three patterns of arteriosclerosis:
atherosclerosis: large and medium-sized arteries
Mönckeberg medial calcific sclerosis: muscular arteries
arteriolosclerosis: small arteries and arterioles
At...