The femoral ring is the superior opening of the femoral canal. Its boundaries are:
medial: lacunar ligament
anterior: medial part of the inguinal ligament
lateral: femoral vein within the intermediate compartment of the femoral sheath
posterior: pectineal ligament overlying the pectineus and...
The term kissing carotids refers to tortuous and elongated vessels which touch in the midline. They can be be found in:
within the pituitary fossa
within sphenoid sinuses
within sphenoid bones
The significance of kissing carotids is two-fold:
may mimic int...
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...
The coronary arteries arise from the coronary sinuses immediately distal (superior) to the aortic valve and supply the myocardium with oxygenated blood. They branch and encircle the heart to cover its surface with a lacy network resembling perhaps a slightly crooked crown.
Nutcracker syndrome is a vascular compression disorder and refers to the compression of the left renal vein between the superior mesenteric artery (SMA) and aorta. This can lead to renal venous hypertension, resulting in rupture of thin-walled veins into the collecting system with resultant haem...
Ischaemic stroke results from a sudden cessation of adequate amounts of blood reaching parts of the brain. Ischaemic strokes can be divided according to territory affected or mechanism.
Stroke is the second most common cause of morbidity worldwide (after myocardial infarction) and...
Rotational vertebral artery occlusion syndrome, also known as Bow Hunter's syndrome, is a rare form of vertebrobasilar insufficiency secondary to dynamic compression of the usually-dominant vertebral artery.
It has many predisposing aetiologies, but is most often due to large osteophytes, atla...
Pulmonary embolism (PE) refers to embolic occlusion of the pulmonary arterial system. The majority of cases result from thrombotic occlusion, and therefore the condition is frequently termed pulmonary thrombo-embolism which is what this article mainly covers.
Other embolic sources include:
Duplication of the inferior vena cava is a relatively rare vascular anomaly, but this caval abnormality needs to be recognised, especially in association with renal anomalies like crossed fused ectopia or circumaortic renal collar 1-2.
The incidence of inferior vena caval duplicat...
Minimal aortic injuries are traumatic aortic lesions that usually involve the intima and are recognised more frequently due to the use of high-resolution imaging.
Minimal aortic injuries account for 10-28% of all blunt traumatic aortic injuries 1,6,7. The proportion of this type o...
A left-sided superior vena cava (SVC) is the most common congenital venous anomaly in the chest, and in a minority of cases can result in a right-to-left shunt 3-4.
A left-sided SVC is seen in 0.3-0.5% of the normal population and in ~5% of those with congenital heart disease 3. I...
The inferolateral trunk, along with the meningohypophyseal trunk, is a branch of the C4 segment of the internal carotid artery. It is identified in up to 80% of dissection specimens but is less frequently seen on imaging.
It is also referred to as the artery to the inferior cavernous sinus, ari...
The bronchial veins are counterparts to the bronchial arteries and drain the bronchi, hilar structures and the mid-portion of the oesophagus.
There is typically a single bronchial vein at each hilum, formed from the superficial bronchial veins with deep bronchial veins draining i...
Central nervous system (CNS) vasculitides represent a heterogeneous group of inflammatory diseases affecting the walls of blood vessels in the brain, spinal cord, and the meninges.
Please refer to the article on vasculitis for a general discussion of that entity.
The aim of this article will ...
Phlegmasia cerulea dolens (Greek: "inflamed blue oedema") is an uncommon complication of deep venous thrombosis, which results from extensive thrombotic occlusion of the major and collateral veins of an extremity (usually the legs).
It is characterised by severe pain, swe...
The transverse sinus is one of the dural venous sinuses and drains the superior sagittal sinus, the occipital sinus and the straight sinus, and empties into the sigmoid sinus which in turn reaches the jugular bulb.
The two transverse sinuses arise at the confluence of the three aforementioned s...
Syphilitic aortitis is a form of aortitis which occurs due to syphilis. It usually occurs in tertiary syphilis often 10-30 years after initial infection.
progression into a luetic aneurysm
aortic valvular insufficiency
coronary ostial involvement with coronary ostial stenosis
Thoracic aortic aneurysms are relatively uncommon compared to abdominal aortic aneurysms. There is a wide range of causes, and the ascending aorta is most commonly affected. CTA and MRA are the modalities of choice to image this condition.
The term aneurysm is used when the axial d...
Aortitis refers to a general descriptor that involves a broad category of infectious and non-infectious conditions where there is inflammation (i.e. vasculitis) of the aortic wall.
The presentation is non-specific with fever, pain and weight loss.
The Raymond–Roy occlusion classification (RROC) is an angiographic classification scheme for grading the occlusion of endovascularly treated intracranial aneurysms 1. It is also known as the Raymond class, Montreal scale, modified Montreal scale or the Raymond Montreal scale.
class I: complete ...
Congenital coronary artery anomalies (CCAAs) are not common, found only in ~1% (range 0.1-2%) of patients 1,3.The most important finding to look for is the "malignant" course of anomalous coronary artery, namely, does the artery run between big pulsating objects - RVOT and pulmonary artery on on...
The superior anastomotic vein (or vein of Trolard) connects the superior sagittal sinus and the superficial middle cerebral vein (of Sylvius).
Its size is dictated by the relative size of the superficial middle cerebral vein and the anastomotic vein of Labbé. The vein of Trolard is smaller than...
The superficial middle cerebral vein (SMCV) (also known as the Sylvian vein) is one of the superficial cerebral veins. It usually passes along the Sylvian fissure posteroanteriorly, it collects numerous small tubutaries which drain the opercular areas around the lateral sulcus. It curves anterio...
The hepatic veins are three large intraparenchymal veins which drain the liver substance into the inferior vena cava (IVC), named the right hepatic vein, middle hepatic vein and left hepatic vein. The veins are important landmarks, running in between and hence defining the segments of the liver....
The vein of Labbé, also known as inferior anastomotic vein, is part of the superficial venous system of the brain.
The vein of Labbé is the largest channel that crosses the temporal lobe between the Sylvian fissure and the transverse sinus and connects the superficial middle cerebral vein to t...
Budd-Chiari syndrome refers to the clinical picture that occurs when there is partial or complete hepatic venous outflow obstruction. It is characterised on imaging by ascites, caudate hypertrophy, peripheral atrophy, and prominent collateral veins.
Budd-Chiari syndrome is rare. ...
Griesinger sign, named after Wilhelm Griesinger, a German psychiatrist and neurologist (1817-1868) refers to oedema of the postauricular soft tissues overlying the mastoid process as a result of thrombosis of the mastoid emissary vein. It is a complication of acute otomastoiditis and may be asso...
The cremasteric artery is a small branch of the inferior epigastric artery that enters the deep inguinal ring of the inguinal canal and supplies the layers of the spermatic cord and also the skin of the scrotum, including the cremaster muscle.
History and etymology
The word "cremaster" derives...
The testicular arteries (also known as the spermatic arteries) are the long, small-diameter gonadal arteries in the male that supply the testis alongside the cremasteric artery and the artery to the ductus deferens.
As paired structures they arise symmetrically, slightly...
Developmental venous anomaly (DVA), also known as cerebral venous angioma, is a congenital malformation of veins which drain normal brain. They were thought to be rare before cross-sectional imaging but are now recognised as being the most common cerebral vascular malformation, accounting for ~5...
Coronary Artery Disease - Reporting and Data System (CAD-RADSTM) classification is proposed by the Society for Cardiovascular Computed Tomography (SCCT), the American College of Radiology (ACR), and the North American Society for Cardiovascular Imaging (NASCI), last updated in 2016.
Vena cava filter is an endovascular device which is typically placed in the infrarenal inferior vena cava (IVC) to prevent pulmonary embolism in selected patients. This procedure is most often performed by interventional radiologists under fluoroscopic guidance.
Contrast enhanced MR angiography (MRA) is a technique involving 3D spoiled gradient-echo (GE) sequences, with administration of gadolinium-based contrast agents (GBCA). It can be used to assess vascular structures of almost any part of the body. Its key features are:
T1 weighted spoiled gradien...
Cardiac MRI consists of using MRI to study heart anatomy, physiology and pathology.
The main advantages of cardiac MRI in comparison with other techniques are:
better definition of soft tissues
use of different types of sequences improves diagnostic accuracy
no ionising radiation...
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
Phase contrast imaging is an MRI technique that can be used to visualise moving fluid. It is typically used for MR venography as a non-IV-contrast requiring technique.
Spins that are moving in the same direction as a magnetic field gradient develop a phase shift that is proportional to the vel...
Microvascular obstruction (MVO), also known as no reflow phenomenon, is an established complication encountered in coronary angioplasty for prolonged acute myocardial infarction.
The phenomenon results from obstruction of the myocardial microcirculation, which is composed of vessel...
The ophthalmic artery (OA) is a branch off the C6 segment of the internal carotid artery (ICA).
OA arises medial to the anterior clinoid process as the ICA exits the cavernous sinus. It originates from the antero- or supero-medial surface of the ICA.
OA passes in...
Terson syndrome refers to vitreous haemorrhage associated with subarachnoid haemorrhage, however some authors include retinal haemorrhage as well. The syndrome is a poor prognostic marker in patients with subarachnoid haemorrhage.
Terson syndrome has been reported to occur in 13-5...
Cervical aortic arch is a rare aortic arch anomaly characterised by an elongated, high-lying aortic arch extending at or above the level of the medial ends of the clavicles.
Patients with cervical aortic arch are usually asymptomatic. Symptomatic patients may present with...
Portal vein thrombosis may be seen in a variety of clinical contexts, and when acute can be a life-threatening condition. It is a major cause of non-cirrhotic presinusoidal portal hypertension. Portal vein thrombus may be either bland and/or malignant (i.e. tumour thrombus), and it is a critical...
The Mickey Mouse sign is said to represent the normal anatomy of the common femoral artery, common femoral vein and great saphenous vein on ultrasound at the level just inferior the inguinal crease.
Mickey Mouse appearance
The diaphragm is the dome-shaped muscle that separates the thoracic cavity from the abdominal cavity, enclosing the inferior thoracic aperture.
The muscular fibres of the diaphragm originate around the circumference of the inferior thorax and converge to a common insertion point ...
The floating viscera sign is an angiographic sign that occurs when there is visualisation of branches of the abdominal aorta (e.g. coeliac axis, superior mesenteric artery, and renal arteries) during aortography with little or no visualisation of the aortic lumen.
it indicates the presence of a...
The floating aorta sign refers to displacement of the abdominal aorta away from the vertebral column.
It is a radiographic/CT sign of retroperitoneal masses.
On lateral lumbar spine radiographs, the expected location of the posterior aortic wall is expected to be ≤10 mm ...
The jejunal and ileal branches of the superior mesenteric artery are variable in number.
They pass in the two layers of the mesentery to the jejunum and ileum and progressively divide and join in a series of anastomosing arcades. From the arcades, straight arteries (also known as the vasa recta...
The right coronary artery (RCA) is one of the two main coronary arteries that supply the heart with oxygenated blood.
It is a branch of the ascending aorta, with its normal origin in the right aortic sinus, just superior to the aortic valve
The RCA courses to th...
The conus artery is a small early branch off the right coronary artery (RCA) circulation.
The artery has a variable distribution, but usually supplies a region of the anterior interventricular septum and the conus of the main pulmonary artery (hence its name).
Double aortic arch is the most common symptomatic type of the aortic arch variant. It may account for up to 50-60% of vascular rings.
Double aortic arch is mostly diagnosed in childhood due to of symptoms related to oesophageal and/or tracheal obstruction. Respiratory sym...
Central venous catheters (CVC) or lines (CVL) refer to a wide range of central venous access devices but can broadly be divided into four categories. They may be inserted by medical, surgical, anaesthetic/ITU, or radiology specialists.
peripherally inserted central catheters (PI...
Pulmonary arterial calcification is the phenomenon which is usually seen in the setting of advanced pulmonary hypertension. It can however be uncommonly present in those without pulmonary hypertension.
The general mechanism in the vast majority is thought to be from high end pulmonar...
Renal artery stenosis (RAS) refers to a narrowing of a renal artery. When the process occurs slowly, it leads to secondary hypertension. Acute renal artery stenosis does not lead to hypersecretion of renin.
When the stenosis occurs slowly, collateral vessels form and supply the kidne...
The right pulmonary artery (RPA) is one of the branches of the pulmonary trunk, branching at the level of the transthoracic plane of Ludwig. It is longer than the left pulmonary artery and courses perpendicularly away from the pulmonary trunk and left pulmonary artery, between the superior vena ...
The left pulmonary artery (LPA) is one of the branches of the pulmonary trunk, branching at the level of the transthoracic plane of Ludwig. It is shorter than the right pulmonary artery and represents a direct posterior continuation of the pulmonary trunk. It arches posterosuperiorly over the su...
Coeliac artery compression syndrome is also known as coeliac axis syndrome, median arcuate ligament syndrome and Dunbar syndrome. It is characterised by upper abdominal angina secondary to compression of the coeliac trunk by the diaphragmatic crurae.
The median arcuate ligament is th...
The empty delta sign is a CT sign of dural venous sinus thrombosis of the superior sagittal sinus, where contrast outlines a triangular filling defect (thrombus). It is only described with CECT-scan or MRI, not with NECT nor non-contrast MRI.
The exact mechanism for this appearance i...
The ulnar artery is a terminal branch of the brachial artery, arising at the proximal aspect of the forearm. Along with the radial artery, it is one of the main arteries of the forearm.
origin: terminal branch of the brachial artery
location: inferior aspect of the cubital fossa
The "dog leg" sign is a secondary angiographic sign on popliteal angiography, which demonstrates an irregular lumen of the popliteal artery with acute bend in the course of the popliteal artery. It is characteristically seen in popliteal artery aneurysms with mural thrombus.
It is an important ...
Hereditary haemorrhagic telangiectasia (HHT), also known as Osler-Weber-Rendu syndrome, is a rare inherited disorder characterised by abnormal blood vessel formation in the skin, mucous membranes, and organs including the lungs, liver, and central nervous system.
Umbilical venous catheters are commonly used in the neonatal period for vascular access and should be carefully assessed for position on all neonatal films.
An umbilical venous catheter generally passes directly superiorly and remains relatively anterior in the abdomen. It passes thr...
Tear drop sign of the superior mesenteric vein (SMV) is one of the important signs in the staging of pancreatic adenocarcinoma. Its importance lies in its diagnosis as well as prognostic significance. This sign is used in assessing the resectability of pancreatic cancer.
Acute occlusion of the basilar artery may cause brainstem or thalamic ischaemia or infarction. It is a true neuro-interventional emergency and, if not treated early, brainstem infarction results in rapid deterioration in the level of consciousness and ultimately death.
A hepatic lymphangioma is a rare benign condition that corresponds to focally dilated lymphatic channels in the liver.
Most cases are asymptomatic.
A lymphangioma is a benign lesion that can occur at almost any location in the body. Hepatic involvement is les...
Polymyalgia rheumatica (PMR) is a common inflammatory condition typically affecting elderly people. It is a multisystem disorder but usually affects the musculoskeletal system.
It can manifest in various ways, which are best discussed in the separate articles below:
polymyalgia rheumatica: mus...
Pericardial calcification usually occurs in patients with a history of pericarditis.
previous trauma or prior pericarditis
later sequelae of rheumatic heart disease
malignant pericardial involvement (e.g. mediastinal teratoma)
On chest radiography, location of...
Getting a film with traumatic aortic injury in the exam is one of the many exam set-pieces that can be prepared for.
This is one of the cases you should look and not speak for 10 seconds as there tends to be a lot of findings on the film of patients with traumatic aortic injury.
The disappearing basal ganglia sign is one of the early signs of a middle cerebral artery (MCA) infarction. It is defined as the loss of delineation of the basal ganglia, due to blurring of their grey-white matter interface and hypoattenuation, consequent to cytotoxic oedema at the time of an is...
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...
Isolated unilateral absence of the pulmonary artery (IUAPA) is the congenital absence of the left or right pulmonary artery. When found in combination with other congenital vascular abnormalities it is known as unilateral absence of the pulmonary artery (UAPA).
Pinch-off syndrome is a spontaneous catheter fracture, which is seen as a complication of subclavian venous catheterisation.
It is a known complication of central venous catheterisation with a much-reduced incidence in current practice and is generally considered to be rare.
Corona mortis, Latin for "crown of death", is a common variant vascular anastomosis between the external iliac artery or deep inferior epigastric artery with the obturator artery. It is reported to be present in a third of patients on routine multi-detector CT examination 1, 4.
Knowledge of th...
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)
Cystic hygroma, also known as cystic or nuchal lymphangioma, refers to the cystic variety of congenital lymphangioma which, most commonly, occur in the cervicofacial regions, particularly at the posterior cervical triangle.
They usually occur in the fetal/infantile and paediatri...
The superior thoracic artery is the only branch of the first part of the axillary artery. It is only a small and highly variable artery.
Origin and course
The superior thoracic artery originates from the first part of the axillary artery, just inferior to subclavius. It courses...
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...
Partial anomalous pulmonary venous return (PAPVR), also known as partial anomalous pulmonary venous connection (PAPVC), is a rare congenital cardiovascular condition in which some of the pulmonary veins, but not all, drain into the systemic circulation rather than in the left atrium.
A coronary artery bypass graft (CABG or CAG) is placed during a surgical procedure to increase blood flow to the myocardium due to coronary stenoses, usually caused by coronary artery disease. Arteries or veins can be grafted during this procedure.
Long term outcome of coronary artery bypass gr...
Iliac vein occlusion can be due to the variety of causes including:
catheter dissection injuries
IVC filter insertion
direct tumour invasion
enlarged lymph nodes
Moyamoya syndrome, also termed the moyamoya pattern or phenomenon, is due to numerous conditions that can cause arterial occlusion of the circle of Willis, with resultant collaterals, and appearances reminiscent of moyamoya disease. These conditions include 1-4 :
vessel wall abnormalities
Carotid artery stenosis also referred as extracranial carotid artery stenosis, is usually caused by an atherosclerotic process and is one of the major causes of stroke and transient ischemic attack (TIA) 1.
This article refers to stenosis involving carotid bulb and the proximal segment of inte...
Carotid pacemaker, also known as implantable carotid sinus stimulators, is a device that delivers activation energy through the carotid leads and the leads conduct activation energy to the carotid baroreceptors. This is sometimes offered for drug-resistant hypertension. The baroreceptors send si...
Pulmonary hypertension is defined as a resting mean pulmonary arterial pressure of 25 mmHg or greater at right heart catheterisation, which is a haemodynamic feature that is shared by all types of pulmonary hypertension in the Dana Point classification system. A resting mean pulmonary arterial p...
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...
Lymphedema is the pathologic accumulation of fluid in the soft tissues as the result of impaired lymphatic drainage, with resultant inflammation, adipose tissue hypertrophy, and fibrosis. It can be either primary or secondary, due to surgery or disease processes. The condition can cause disfigur...
The cavernous sinuses are paired dural venous sinuses.
The cavernous sinus (CS) is located on either side of the pituitary fossa and body of the sphenoid bone between the endosteal and meningeal layers of the dura. The normal lateral wall should be either straight or concave.
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...
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 a...
Endoleaks occur when an aneurysmal sac continues to be pressurised despite endoluminal stent placement.
There are five types:
type I: leak at graft ends (inadequate seal) - most common after repair of thoracic aortic aneurysms 4
Ic: iliac occluder
A type III endoleak is a type of endoleak which usually occurs through a defect in the graft. It may be divided into two components.
IIIa: junctional separation of the modular components
IIIb: fractures or holes involving the endograft
It is relatively uncommon and only occurs ...
Endoleaks are characterised by persistent blood flow within the aneurysm sac following endovascular aneurysm repair (EVAR). Normally the aortic stent-graft used for EVAR excludes the aneurysm from the circulation by providing a conduit for blood to bypass the sac.
An endoleak is a...
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 calibre vessel
supplies the medial side of the foot, abductor hallucis and flexor digitorum brevis.
provides the arter...
Rhupus syndrome is a term traditionally used to describe patients uncommonly having the coexistence of
systemic lupus erythematosus (SLE) and
rheumatoid arthritis (RA)
Veins of Sappey are small veins around the falciform ligament that drain the venous blood from the anterior part of the abdominal wall directly into the liver. This flow dilutes the portal perfusion at these sites, causing hepatic pseudolesions.
The superior vein of Sappey drains...