An Arc of Buhler aneurysm is a rare pathology that can occur in an arc of Buhler. It can occur in association with stenoses of celiac axis. This is considered a true aneurysm. Transcatheter embolization has been successfully tried as the management technique.
On imaging ...
The arc of Riolan, also known as the mesenteric meandering artery (of Moskowitz) or central anastomotic mesenteric artery, is an arterioarterial anastomosis between the superior and inferior mesenteric arteries.
It is an inconstant artery that connects the proximal superior mesen...
The peri-articular arterial anastomosis of the elbow consists of several arteries that supply the elbow joint and its supporting structures. It functions to allow blood to flow around the elbow joint no mater which position the joint is in. The arteries that contribute include:
from the brachi...
Arterial dissection occurs when blood enters the media through a tear or ulcer in the intima and tracks along the media, forming a second blood-filled channel within the wall. The normal lumen lined by intima is called the true lumen and the blood-filled channel in the media is called the false ...
In patients with a left ventricular assist device (LVAD), spectral Doppler waveforms are altered due to continuous flow provided by the pump in the device:
waveforms are monophasic with a constant antegrade flow and no flow below the baseline.
the waveform is typically parvus-tardus with a slo...
The arteries of the head and neck are branches of the common carotid and subclavian arteries.
common carotid artery
internal carotid artery (segments)
persistent stapedial artery
The arterial supply of the lower limbs is via vessels arising from the external iliac artery.
The common femoral artery (CFA) is the direct continuation of the external iliac artery. It begins at the level of the inguinal ligament. It terminates as it gives off the profunda femoris and continu...
The arterial supply of the upper limb is derived from the subclavian artery. The right subclavian artery originates from the brachiocephalic artery, which is the first branch of the aortic arch. The left subclavian artery originates directly from the aortic arch, being the third branch.
Arterial supply to the foot can be divided into plantar and dorsal components.
Plantar arterial supply
Medial plantar artery
branch off the posterior tibial artery
smaller caliber vessel
supplies the medial side of the foot, abductor hallucis and flexor digitorum brevis.
provides the arter...
The arterial supply to the hand is comprised of a complex vascular network formed from the branches and distal continuations of the radial and ulnar arteries. This rich vascular network can be divided into palmar and dorsal components.
Palmar arterial supply
The palmar arterial supply can be d...
Arteriosclerosis is defined by thickening and loss of elasticity of the arterial walls.
There are three patterns (arteriosclerosis is used as a generic term for all patterns above):
atherosclerosis: large and medium-sized arteries
Mönckeberg medial calcific sclerosis: muscular arteries
Arteriovenous access is required for haemodialysis in renal failure patients. The upper limb is generally preferred as a site, however, lower limb access can also be obtained. Ultrasound is the preferred modality for evaluation of the vessels prior to creating an access.
An arteriovenous fistula (AVF) is an abnormal connection between an adjacent artery and vein. Unlike an arteriovenous malformation (AVM), these are frequently acquired lesions, rather than developmental abnormalities.
Arteriovenous fistulas have a number of etiologies. They can be ia...
Arteriovenous malformations (AVMs) are characterized by an abnormal leash of vessels allowing for arteriovenous shunting. They can occur anywhere in the body but have a predilection towards the head and neck. There is a direct arteriovenous communication with no intervening capillary bed. They ...
The artery of Adamkiewicz, also known as the great anterior radiculomedullary artery or arteria radicularis anterior magna, is the name given to the dominant thoracolumbar segmental artery that supplies the spinal cord.
The artery of Adamkiewicz has a variable origin but ...
The artery of Percheron is a rare variant of the posterior cerebral circulation characterized by a solitary arterial trunk that supplies blood to the paramedian thalami and the rostral midbrain bilaterally. From the original classification of arterial patterns at the origin of the paramedian art...
Artery of Percheron territory infarct is rare, on account of the relative rarity of the artery of Percheron, and presents with a variety of signs and symptoms collectively termed the paramedian thalamic syndrome. It is a type of posterior circulation infarction.
On imaging, it is classically ch...
The artery to the ductus deferens (deferential or vesiculodeferential artery) is a branch of the superior vesical artery, which in turns arises from the internal iliac artery via the umbilical artery.
origin: superior vesical artery
main branch: no named branches
The ascending aorta is the first part of the aorta, and begins at the aortic valve, located obliquely just to the left of the midline at the level of the the third intercostal space. It terminates as it exits the fibrous pericardium where it becomes the aortic arch, in the plane of Ludwig, a hor...
Dilatation of the ascending aorta is a common finding in the elderly but unusual in younger patients.
In adults, an ascending aortic diameter greater than 4 cm is considered to indicate dilatation 4. Aneurysmal dilatation is considered when the ascending aortic diameter reaches or ex...
Ascending aortic aneurysms are the most common subtype of thoracic aortic aneurysms and may be true or false injuries.
Ascending aortic aneurysms represent 60% of thoracic aortic aneurysms.
Typically ascending aortic aneurysms are an incidental finding an...
The ascending cervical artery is 1 of the 4 branches of the thyrocervical trunk (off the first part of the subclavian artery).
It is a small artery that ascends medial to the phrenic nerve on the prevertebral fascia. It contributes many small spinal branches into the intervertebral foramina of ...
The ascending lumbar communicant vein is a communication between the left ascending lumbar vein and the left renal vein. Because of its retroperitoneal location, when dilated, it may be mistaken for a lymph node on non-contrast studies with thick collimation.
The image shows the left renal vein...
The ascending lumbar vein is a paired structure which forms a part of the venous drainage of the lumbar vertebral column.
location: near midline on the side of the vertebral column in the lumbar region
origin and termination: continuation of the lateral sacral veins; joins the subcost...
The ascending pharyngeal artery, the smallest branch of the external carotid artery, is a long, slender vessel, deeply seated in the neck, beneath the other branches of the external carotid and under the stylopharyngeus.
origin: a branch of the external carotid artery
The axillary artery represents the continuation of the subclavian artery and is a major artery of the upper limb.
origin: continuation of the subclavian artery as it passes under the midpoint of the clavicle on the outer edge of the first rib
termination: continues as the brachial ar...
Useful mnemonics to remember the branches of the axillary artery are:
S AL SAP
Screw the lawyer, save a patient!
S AL SAP
The gap between the 'S' and the 'AL' to emphasize that 'S' is 1st part and 'AL' are 2nd part
S: superior thoracic artery (from 1st part)
A: acromiothoracic (...
The axillary vein is one of the major veins of the upper limb. It is formed by the union of the paired brachial veins and the basilic vein and contributes to the drainage of the axilla, arm and superolateral chest wall.
origin: formed by the union of the paired brachial veins and the b...
An azygos anterior cerebral artery is uncommon to rare variant of the circle of Willis where the two A1 segments of the anterior cerebral artery (ACA) join to form a single trunk. As a result, there is no anterior communicating artery. This organization is similar to that seen in lower primates ...
An azygos arch valve refers to a venous valve at the site of the azygos arch. They are considered common and are more frequently seen at CT when high contrast material injection rates and right arm injections are used 2. They can be of various sizes and shapes, and many of them show features of ...
Azygos continuation of the inferior vena cava (also known as absence of the hepatic segment of the IVC with azygos continuation) is an uncommon vascular anomaly and is a cause of a dilated azygos vein.
Azygos continuation of the IVC has a prevalence ~1.5% (range 0.2-3%) 1.
The azygos vein is a unilateral vessel that ascends in the thorax to the right side of the vertebral column, carrying deoxygenated blood from the posterior chest and abdominal walls. It forms part of the azygos venous system.
Spelling it "azygous" when referring to the vein is inco...
The azygos (venous) system is a collective term given to the H-shaped configuration of the azygos, hemiazygos, accessory hemiazygos veins and left superior intercostal vein.
It is responsible for draining the thoracic wall and upper lumbar region via the lumbar veins and posterior intercostal v...
Balloon-occluded retrograde transvenous obliteration (BRTO) is a technique used by interventional radiologists in the treatment of gastric varices, particularly those with prominent infra-diaphragmatic portosystemic venous shunts (e.g. gastro-renal and gastro-caval shunts).
The technique is mor...
Barrow caroticocavernous fistula classification divides caroticocavernous fistulas into direct (type A) or indirect (types B-D). This classification was proposed by Barrow et al. in 1985 1 and at the time of writing (mid 2016) remains the most widely used system for describing caroticocavernous ...
Basal ganglia hemorrhage is a common form of intracerebral hemorrhage, and usually as a result of poorly controlled long-standing hypertension. The stigmata of chronic hypertensive encephalopathy are often present (see cerebral microhemorrhages).
Other sites of hypertensive hemorrhages are the ...
The basal veins, also known as the veins of Rosenthal, are paired, paramedian veins which originate on the medial surface of the temporal lobe and run posteriorly and medially. It passes lateral to the midbrain through the ambient cistern to drain into the vein of Galen with the internal cerebra...
The basilar artery is part of the posterior cerebral circulation. It artery arises from the confluence of the left and right vertebral arteries at the base of the pons as they rise towards the base of the brain.
origin: vertebral artery confluence
course: ventral to pons in the pontin...
Basilar artery aneurysms are less common than anterior circulation aneurysms, and rupture less frequently, but their critical location necessitates careful evaluation.
may present as a lobulated hyperattenuating structure anterior to the mid brain
rupture of a basil...
Basilar artery fenestration (or more simply, basilar fenestration) is the most common intracranial arterial fenestration. It refers to duplication of a portion of the artery, thought to occur due to failed fusion of plexiform primitive longitudinal neural arteries 4. Its reported prevalence is h...
Basilar artery hypoplasia is a rare vascular anomaly of the basilar artery.
Basilar artery hypoplasia is usually accompanied by one or more fo the following:
persistent carotid-vertebrobasilar anastomoses
hypoplastic V4 segments of the vertebral arteries
The basilar venous plexus lies between the endosteal and visceral layers of the dura on the inner surface of the clivus. It connects the:
inferior petrosal sinuses
superior petrosal sinuses
internal vertebral venous plexus
marginal sinus (around the...
The basilic vein, along with the cephalic vein, is one of the primary superficial veins that drain the upper limb 1. It courses through both the forearm and arm, and contributes to the formation of the axillary vein.
origin: ulnar aspect of the superficial venous network of the dorsum ...
Batson venous plexus, also known as Batson veins, are a network of veins with no valves that connect deep pelvic veins draining the bladder, prostate, and rectum to the internal vertebral venous plexus 1. These veins are important because they are believed to provide a route for spread of pelvic...
The beak sign of arterial dissection is the acute angle formed at the edge of the false lumen in aortic dissection in axial cross-section. It is formed by the borders of the outer aortic wall and the intimal flap, and may be partially thrombosed (blunted beak). It is a reliable characteristic wh...
The Biffl scale or grade illustrates the spectrum of blunt cerebrovascular injury (BCVI) seen on angiography (both CTA and DSA). Some authors refer to the grading scale as the Denver scale, which is not to be confused with the Denver criteria, a series of clinical indications and risk factors fo...
Bland thrombus is a term used to describe any non-malignant venous thrombus (e.g. a "normal" DVT). However the term is most often used in the context of malignancy, to differentiate non-malignant clot from the malignant form, as management of the two may differ; of course they often coexist.
Blooming or color bleed artifact occurs when the color signal indicating blood flow extends beyond its true boundaries, spreading into adjacent regions with no actual flow.
This artifact mainly affects the portion of the image distal to the vessel and the transducers. It is somewhat similar to ...
Blue rubber bleb nevus syndrome (BRBNS) or Bean syndrome, is a rare sporadic syndrome characterized by multifocal venous anomalies. Patients often have multiple soft blue skin lesions associated with multiple bowel venous malformations, which could lead to lower gastrointestinal bleeding.
Blunt cerebrovascular injury (BCVI) is an uncommon but serious consequence of blunt trauma to the head and neck.
It is often part of multi-trauma with a significant series of blunt trauma CTA reporting an incidence of approximately 1% 3. A large systematic review and meta-analysis...
The Borden classification of dural arteriovenous fistulas (DAVF) groups these lesions into three types based upon the site of venous drainage and the presence or absence of cortical venous drainage. It was first proposed in 1995 1. At the time of writing (July 2016), it is probably less popular ...
Bouthillier et al. described (in 1996) 1 a seven segment internal carotid artery (ICA) classification system. It remains the most widely used system for describing ICA segments at the time of writing (mid-2016).
There are a few other classifications systems including those proposed by Fisher (1...
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.
A bovine arch is apparent in ~15% (range 8-25%) of the population and is more common in individuals of African descent. ...
The brachial artery is the main supply of arterial blood to the arm, forearm and hand.
origin: continuation of the axillary artery distal to teres major
location: medial upper arm
supply: muscles of the arm, forearm and hand
main branches: profunda brachii
terminal branches: radia...
The brachial vein is a component of the deep venous system of the upper limb. After forming from the radial and ulnar veins1, the brachial vein travels from the cubital fossa superiorly to become the axillary vein.
origin: union of the ulnar and radial veins in the cubital fossa1
The brachiocephalic trunk (BCT) is a major vessel that supplies the head, neck and right arm. The BCT has previously been known as the innominate artery.
The BCT is the first of the three main branches of the aortic arch, which originates from the upward convexity. It measures 4...
Brachiocephalic trunk pseudoaneurysms are rare.
The brachiocephalic trunk is the second most common site of chest vascular injury. Pseudoaneurysms can measure up to 4-5 cm in length with a diameter of 1.2 cm.
Most common causes are traumatic or iatrogenic injuries.
Treatment and ...
Brachiocephalic veins (BCV), previously the innominate veins are large paired valveless asymmetric veins that drain the head, neck, upper limbs and part of the thorax and mediastinum.
In the root of the neck, the internal jugular and subclavian veins unite to form the bra...
A useful mnemonic to remember the branches of the anterior and posterior divisions of the internal iliac artery is:
I <3 U SUMO SIL which reads as "I love you sumo Sil"
I: internal pudendal artery
I: inferior vesical artery *
I: inferior gluteal artery
U: uterine artery (in femal...
Useful mnemonics to remember the branches of the internal carotid artery is:
A VIP'S COMMA
Calming voices make intra operative surgery pleasurable and almost memorable.
A VIP'S COMMA
A: anterior choroidal artery (C7)
V: Vidian artery (C2)
I: inferolateral trunk (C4)
A useful mnemonic to remember the branches of the internal iliac artery is:
I Love Going Places In My Very Own Underwear!
I: iliolumbar artery
L: lateral sacral artery
G: gluteal (superior and inferior) arteries
P: (internal) pudendal artery
I: inferior vesical (vaginal in female...
A mnemonic for remembering the branches of the maxillary artery is:
DAM I AM Piss Drunk But Stupid Drunk I Prefer, Must Phone Alcoholics Anonymous
D: deep auricular artery
A: anterior tympanic artery
M: middle meningeal artery
I: inferior alveolar artery
A: accessory meningeal ar...
A useful mnemonic to remember the branches of the ophthalmic artery is:
D: dorsal nasal artery
R: (central) retinal artery
M: muscular artery
C: ciliary arteries (long, short and anterior)
L: lacrimal artery
E: ethmoidal arteries (anterior and posterior)
Mnemonics to remember the branches of the anterior division of the internal iliac artery are:
SOI VU MR PIG (it can be remembered as SO fourth (IV) U MR PIG)
Oranges Under Some Ice Might Peel Instantly
SOI VU MR PIG
S: superior vesical artery
O: obturator artery
IV: inferior ves...
Mnemonics for the branches of the external carotid artery abound. A few colourful examples include:
Some American Ladies Found Our Pyramids Most Satisfactory
Some Anatomists Like Freaking Out Poor Medical Students
She Always Likes Friends Over Papa, Sister, and Mama
There are many many many...
Mnemonics to remember the three branches of the posterior division of the internal iliac artery include:
I Love Sex
I Love Sex
I: iliolumbar artery
L: lateral sacral artery
S: superior gluteal artery
P: posterior division of the internal iliac artery
Useful mnemonics to remember the four branches of the thoracoacromial artery are:
CAlifornia Police Department
Cadavers Are Dead People
B: breast (pectoral)
CAlifornia Police Department
Breast aneurysms are a rarely seen cause of a breast mass.
true aneurysm: occurs post trauma and is seen as a slowly enlarging pulsatile mass
false aneurysm / pseudoaneurysm: occurs in acute trauma, post percutaneous biopsy, due to spontaneous hemorrhage secondary to coagulop...
Breast varix is, as the name suggests, varices in the breast that are focally dilated veins in the breast.
If varices are seen bilaterally then a cause for central venous obstruction (superior vena cava syndrome) could be the underlying etiology with the varices being a part of the ...
Bronchial arterial aneurysm refers to any form of aneurysmal dilatation involving any segment of the bronchial artery. The term is sometimes used synonymously with a bronchial arterial pseudoaneurysm 2.
They are a rare entity and are reported in <1% of those who undergo selective ...
The bronchial arteries are the major supply of high-pressure oxygenated blood to the supporting structures of the lung, including the pulmonary arteries, yet they are responsible for only 1% of the lung blood flow overall.
Bronchial artery anatomy is variable, most commonly classified according...
The bronchial veins are counterparts to the bronchial arteries and drain the bronchi, hilar structures and the mid-portion of the esophagus.
There is typically a single bronchial vein at each hilum, formed from the superficial bronchial veins with deep bronchial veins draining in...
The buccinator artery is a small branch from the second part of the maxillary artery. It runs obliquely forward, between the medial pterygoid and the insertion of the temporalis, to the outer surface of the buccinator, to which it is distributed, anastomosing with branches of the facial artery a...
Budd-Chiari syndrome refers to the clinical picture that occurs when there is partial or complete hepatic venous outflow obstruction. It is characterized on imaging by ascites, caudate hypertrophy, peripheral atrophy, and prominent collateral veins.
Budd-Chiari syndrome is rare. ...
Buerger disease, also known as thromboangiitis obliterans, is a chronic, non-atherosclerotic, inflammatory, thrombotic arteritis found predominantly in young male smokers.
Patients may initially present with nonspecific symptoms such as hand and foot claudication, which e...
The Cabrol shunt or Cabrol fistula, also known as a perigraft-to-right atrial shunt, is a technique used for uncontrolled bleeding following aortic root operations.
The Cabrol shunt is applied when bleeding from an aortic root reconstruction cannot be controlled by traditional means ...
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 th...
Calcified cerebral embolus is an uncommon and often overlooked cause of embolic ischemic stroke.
Although emboli are a common cause of ischemic stroke, calcified cerebral emboli are considered rare. With only a paucity of literature regarding calcified cerebral emboli – only 48 r...
Calciphylaxis, or calcific ureamic arteriolopathy, is a rare condition which manifests as subcutaneous vascular calcification and cutaneous necrosis (small blood vessels of the fat tissue and the skin). Some authors describe as a syndrome of vascular calcification, thrombosis and skin necrosis.
Call-Fleming syndrome, also called Call syndrome, essentially synonymous with the more current term reversible cerebral vasoconstriction syndrome (RCVS), although it is felt to be a subset of the former by some, representing the idiopathic RCVS.
Call-Flemming syndrome is therefore characterize...
The callosomarginal artery, also known as median artery of corpus callosum, is the largest branch of the pericallosal artery. It courses within or posterior to the cingulate sulcus, in parallel orientation to the pericallosal artery. It divides to give two or more cortical branches to supply the...
Calot triangle is a small (potential) triangular space at the porta hepatis of surgical importance as it is dissected during cholecystectomy. Its contents, the cystic artery and cystic duct must be identified before ligation and division to avoid damaging them during the operation.
Capillary hemangiomas of the orbit, also known as strawberry hemangiomas, on account of its coloring, or orbital infantile hemangiomas, are the most common orbital tumors of infancy, and unlike orbital cavernous hemangiomas, they are neoplasms rather than vascular malformations.
The Capps triad refers to the constellation of clinical and imaging findings in patients with spontaneous retropharyngeal hematomas, and consists of:
tracheal and esophageal compression
anterior displacement of the trachea
subcutaneous bruising over the neck and anterior chest
History and et...
A multi-gated (MUGA) cardiac blood pool scan (sometimes just called a MUGA scan) is a common study performed in patients who are receiving potentially cardiotoxic chemotherapy.
acute myocardial infarction (AMI)
coronary artery disease (CAD)
evaluation after coronary artery bypas...
Cardiac MRI consists of using MRI to study heart anatomy, physiology, and pathology.
In comparison to other techniques, cardiac MRI offers:
improved soft tissue definition
protocol can be tailored to likely differential diagnoses
a large number of sequences are available
Cardiac myxomas, although uncommon are one of the commonest primary cardiac tumors and account for ~50% primary benign cardiac tumors.
Cardiac myxomas are the most common primary cardiac tumor in adults but are relatively infrequent in childhood, where cardiac rhabdomyomas are mo...
Cardiac venous malformations (also known as cardiac hemangiomas) consists of a slow flow venous malformation and is composed of numerous non-neoplastic endothelial-lined thin-walled channels with interspersed fat and fibrous septae.
It is important to note that according to newer n...
Carney complex (not to be confused with the Carney triad) is a rare multiple endocrine neoplasia syndrome, which is autosomal dominant and characterized by 1-4:
seen in two-thirds of patients with Carney complex
skin pigmentation (blue naevi): especially of the ...
Caroticocavernous fistulas (CCF) represent abnormal communication between the carotid circulation and the cavernous sinus. They can be classified as direct or indirect which are separate conditions with different etiologies.
Direct CCFs are often secondary to trauma, and as such...
The caroticotympanic branch (tympanic branch) is a small branch from the C2 segment of the internal carotid artery. It is a vestigial remnant of the hyoid artery.
It passes posterolaterally into the middle ear cavity and anastomoses with the inferior tympanic artery (a branch of the external ca...
Carotid arterial stenting (CAS) is a minimally invasive endovascular interventional procedure that can potentially offer the same advantage as surgery (carotid endarterectomy).
Indications for carotid stenting are evolving with endarterectomy trials that evaluate the carotid stenos...
Carotid artery pseudoaneurysms can refer to pseudoaneurysms involving any segment of the carotid arteries:
common carotid artery pseudoaneurysm
internal carotid artery pseudoaneurysm
external carotid artery pseudoaneurysm
As with pseudoaneurysms elsewhere, these lack all three lay...