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Dysphagia lusoria

Dysphagia lusoria is an impairment of swallowing due to compression from an aberrant right subclavian artery (arteria lusoria). Clinical presentation Most patients with aberrant right subclavian arteries do not have symptoms. Some present with mild dysphagia, while a small minority have a seve...

Dural venous sinus thrombosis

Dural venous sinus thrombosis is a subset of cerebral venous thrombosis, often coexisting with cortical or deep vein thrombosis, and presenting in similar fashions, depending mainly on which sinus is involved. As such, please refer to the cerebral venous thrombosis article for a general discuss...

Dural sinus occlusive disease

Dural sinus occlusive disease (DSOD) is an infective form of dural sinus thrombosis (thrombophlebitis) commonly seen in the setting of acute otomastoiditis. It typically presents with: severe headaches high fevers sixth nerve palsy - due to involvement of Dorello's canal altered conscious st...

Ductus diverticulum

Aortic ductus diverticulum is a developmental outpouching of the thoracic aorta which may be mistaken for an acute aortic injury. Gross anatomy It is usually seen at the anteromedial aspect of the aorta at the site of the aortic isthmus, where the ligamentum arteriosum attaches. It is also the...

Arterial dissection

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 ...

Developmental venous anomaly

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 recognized as being the most common cerebral vascular malformation, accounting for ~5...

Dehiscent jugular bulb

Dehiscent jugular bulbs are present when the sigmoid plate between a high riding jugular bulb and the middle ear is absent, allowing the wall of the jugular bulb to bulge into the middle ear cavity. Epidemiology The estimated incidence is ~5% (range 3.5-7%) of the symptomatic population (e.g. ...

DeBakey classification

The DeBakey classification, along with the Stanford classification, is used to separate aortic dissections into those that need surgical repair, and those that usually require only medical management. Both the Stanford and DeBakey systems can be used to describe all forms of the acute aortic sy...

Deep vein thrombosis

Deep vein thrombosis (DVT) most commonly occurs in the lower limbs, however, are not uncommon in the upper limb and neck deep veins. Other types of venous thrombosis, such as intra-abdominal and intracranial, are discussed in separate articles. Terminology The term indeterminate (equivocal) DV...

Cystic hygroma

Cystic hygroma, also known as cystic or nuchal lymphangioma, refers to the congenital macrocystic lymphatic malformations that most commonly occur in the cervicofacial regions, particularly at the posterior cervical triangle in infants. Terminology While these lesions are commonly known as cys...

Constrictive pericarditis

Constrictive pericarditis (or perhaps better termed pericardial constriction) is a type of pericarditis which leads to diastolic dysfunction and potential symptoms of right heart failure. Epidemiology No single demographic is affected as there are numerous causes of constrictive pericarditis....

Congenital vascular anomalies

Congenital vascular anomalies form a subgroup of vascular anomalies present at birth. They comprise both vascular tumors and vascular malformations. Based on the ISSVA classification of vascular anomalies 1 here is a non-comprehensive list with examples of vascular anomalies that are usually co...

Celiac artery compression syndrome

Celiac artery compression syndrome, also known as median arcuate ligament syndrome, Dunbar syndrome, celiac axis syndrome or Harjola-Marable syndrome, is a rare condition characterized by upper abdominal pain in the setting of compression of the celiac trunk by the diaphragmatic crura. Although...

Circle of Willis

The Circle of Willis is an arterial polygon (heptagon) formed as the internal carotid and vertebral systems anastomose around the optic chiasm and infundibulum of the pituitary stalk in the suprasellar cistern. This communicating pathway allows equalization of blood-flow between the two sides of...

Brain arterial vascular territories

An understanding of brain arterial vascular territories is important in understanding stroke and complications from surgery and endovascular procedures. Although one could be excused for thinking that within the brain, such a carefully organized organ, blood supply would be constant, the truth...

Cerebrovascular malformations

Cerebrovascular malformations are vascular malformations related to the vessels that supply the brain and other cranial structures. Classification Over the years, cerebral vascular malformations have been classified in a variety of ways by many authors, often on the basis of the presence or ab...

Cavernous sinus thrombosis

Cavernous sinus thrombosis (CST) is a rare condition, most commonly infectious in nature, and the diagnosis on imaging is not always straightforward. It has high mortality and morbidity rates. Epidemiology Cavernous sinus thrombosis is rare, with ~4.5 cases per 1,000,000 per year 5. It is the ...

Caval variants

Caval variants, the variance of the anatomy of the venae cavae are common, due to the complex embryology of the venous system. Caval variants are important for a number of reasons: to avoid confusion with venous pathology to suggest the presence of frequently associated abnormalities to plan...

Cerebral cavernous venous malformation

Cerebral cavernous venous malformations, also commonly known as cavernous hemangiomas or cavernomas, are common cerebral vascular malformations, usually with characteristic appearances on MRI. It is the third most common cerebral vascular malformation after developmental venous anomaly and capil...

Caroticocavernous fistula

Caroticocavernous fistulas 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. Epidemiology Direct caroticocavernous fistulas are often secondary to tra...

Cardiac blood pool scan

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. Indications acute myocardial infarction (AMI) coronary artery disease (CAD) evaluation after coronary artery bypas...

Cardiac myxoma

Cardiac myxomas, although uncommon are one of the commonest primary cardiac tumors and account for ~50% primary benign cardiac tumors. Epidemiology Cardiac myxomas are the most common primary cardiac tumor in adults (~50%) but are relatively infrequent in childhood, where cardiac rhabdomyomas...

Carney complex

Carney complex (not to be confused with the Carney triad) is a rare multiple endocrine neoplasia syndrome characterized by 1-4: cardiac myxoma often multiple seen in two-thirds of patients with Carney complex skin pigmentation (blue nevi): especially of the face, trunk, lips, and sclera M...

Capillary hemangioma of the orbit

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. Clinical presen...

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL)

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an autosomal dominant microvasculopathy characterized by recurrent lacunar and subcortical white matter ischemic strokes and vascular dementia in young and middle age patients without known va...

Budd-Chiari syndrome

Budd-Chiari syndrome, also known as hepatic venous outflow obstruction (HVOO), refers to the clinical picture that occurs when there is partial or complete obstruction of the hepatic veins. There is no clear consensus regarding the number of occluded veins, some authors claim that there should...

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 8-25%) of the population and is more common in individuals of Afri...

Saccular cerebral aneurysm

Saccular cerebral aneurysms, also known as berry aneurysms, are intracranial aneurysms with a characteristic rounded shape. They account for the vast majority of intracranial aneurysms and are the most common cause of non-traumatic subarachnoid hemorrhage. Terminology Those larger than 25 mm i...

Acute basilar artery occlusion

Acute occlusion of the basilar artery may cause brainstem or thalamic ischemia 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. It is one of the posterior ...

Azygos vein

The azygos vein is a unilateral vessel that ascends in the thorax to the right of the vertebral column, carrying deoxygenated blood from the posterior chest and abdominal walls. It forms part of the azygos venous system. Terminology The spelling azygous when referring to the vein is incorrect,...

Arteriovenous malformation

Arteriovenous malformations (AVMs) are characterized by an abnormal leash of vessels allowing for arteriovenous shunting. They can occur anywhere in the body but are most common in the brain 1. There is direct arteriovenous communication with no intervening capillary bed. They can be congenital ...

Ascending aorta

The ascending aorta is the first part of the aorta and begins at the sinotubular junction (the junction of the aortic root and ascending aorta) and terminates as it exits the fibrous pericardium where it becomes the aortic arch, in the transthoracic plane (of Ludwig). It is located obliquely jus...

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...

Variant anatomy of the aortic arch

Variant anatomy of the aortic arch occurs when there is failure of normal aortic development. It results in a number of heterogenous anomalies of the aorta and its branch vessels. Gross anatomy Normally, the aorta ascends in the superior mediastinum to the level of the sternal notch before arc...

Aortic dissection

Aortic dissection is the prototype and most common form of acute aortic syndromes and a type of arterial dissection. It occurs when blood enters the medial layer of the aortic wall through a tear or penetrating ulcer in the intima and tracks longitudinally along with the media, forming a second ...

Aortic arch

The aortic arch represents the direct continuation of the ascending aorta and represents a key area for a review of normal variant anatomy and a wide range of pathological processes that range from congenital anomalies to traumatic injury. Summary origin: continuation of the ascending aorta at...

Aortic intramural hematoma

Aortic intramural hematoma is an atypical form of aortic dissection due to a contained hemorrhage into the aortic wall usually from the vasa vasorum without an intimal tear. It forms part of the acute aortic syndrome spectrum along with penetrating atherosclerotic ulcer and classical aortic diss...

Aorta

The aorta, the great artery, is the largest artery of the human body and carries oxygenated blood ejected from the left ventricle to the systemic circulation. It is divided into: thoracic aorta ascending aorta aortic arch descending aorta abdominal aorta It has branches from each section a...

Angiosarcoma

Angiosarcomas (like hemangiopericytomas and hemangioendotheliomas) are tumors that arise from vascular structures. They are typically difficult to distinguish from one another on imaging alone. Angiosarcomas, are the most aggressive of the three, frequently having metastases at the time of diag...

String sign (artery)

The angiographic string sign, also known as the carotid string sign or slim sign, refers to the thin string of intravascular contrast material distal to a stenotic focus in the internal carotid artery (ICA). Pathology A thin stripe of flow is caused by decreased pressure and flow distal to th...

Aneurysm

Aneurysms are focal abnormal dilatation of a blood vessel. They typically occur in arteries; venous aneurysms are rare. Aneurysms may also occur in the heart. Pathology Pathological types true aneurysm false aneurysm (or pseudoaneurysm) Etiology Atherosclerotic atherosclerosis N...

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

Accessory right inferior hepatic vein

An accessory right inferior hepatic vein is the most common variation of the hepatic veins, and may be multiple 1. It is present in up to 48% of the population and drains the posteroinferior part of the right lobe directly into the inferior vena cava (IVC) 1-3. Variations in hepatic vascular an...

Aberrant internal carotid artery

Aberrant internal carotid artery is a variant of the internal carotid artery and represents a collateral pathway resulting from involution of the normal cervical portion (first embryonic segment) of the internal carotid artery 5. Gross anatomy There is consequent enlargement of the usually sma...

Aberrant right subclavian artery

Aberrant right subclavian arteries (ARSA), also known as arteria lusoria, are among the commonest aortic arch anomalies. Epidemiology The estimated incidence is 0.5-2% 1. Associations as can be expected from the embryological development of the artery, the right recurrent laryngeal nerve...

Accessory middle cerebral artery

The accessory middle cerebral artery is a variant of the middle cerebral artery (MCA) that arises from the anterior cerebral artery (ACA). It is different from a duplicated middle cerebral artery, in which the duplicated vessel originates also from the distal end of the internal carotid artery (...

Abdominal aortic aneurysm

Abdominal aortic aneurysms (AAA) are focal dilatations of the abdominal aorta measuring 50% greater than the proximal normal segment, or >3 cm in maximum diameter. They can be confined to the abdominal aorta or can continue from the thoracic aorta as part of a thoraco-abdominal aneurysm (TAAA)....

Venous thromboembolism

Venous thromboembolism covers a wide spectrum of diseases. Individual conditions and complicating condition include: head and neck cerebral vein thrombosis dural venous sinus thrombosis cavernous sinus thrombosis deep cerebral vein thrombosis cortical vein thrombosis superior ophthalmic v...

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