Carotid artery dissection is a serious condition in which a tear forms in one of the two main carotid arteries in the neck, allowing blood to enter the artery wall and separate its layers (dissection). This separation can lead to the formation of a blood clot, narrowing of the artery, and restricted blood flow to the brain, potentially resulting in stroke. Symptoms vary depending on the extent and location of the dissection and may include a sudden, severe headache, neck or facial pain, vision changes, a drooping eyelid (

Horner's syndrome Horner's syndrome, also known as oculosympathetic paresis, is a combination of symptoms that arises when a group of nerves known as the sympathetic trunk is damaged. The signs and symptoms occur on the same side (ipsilateral) as it is a lesion ...

), and stroke-like symptoms such as weakness or numbness on one side of the body, difficulty speaking, or loss of coordination. Carotid artery dissection can occur spontaneously or be triggered by trauma, including minor injuries, certain medical conditions, or activities that involve neck movement. It is a leading cause of

stroke Stroke is a medical condition in which poor cerebral circulation, blood flow to a part of the brain causes cell death. There are two main types of stroke: brain ischemia, ischemic, due to lack of blood flow, and intracranial hemorrhage, hemor ...

in young and middle-aged adults. The condition is typically diagnosed through imaging studies, such as

ultrasound Ultrasound is sound with frequency, frequencies greater than 20 Hertz, kilohertz. This frequency is the approximate upper audible hearing range, limit of human hearing in healthy young adults. The physical principles of acoustic waves apply ...

magnetic resonance imaging Magnetic resonance imaging (MRI) is a medical imaging technique used in radiology to generate pictures of the anatomy and the physiological processes inside the body. MRI scanners use strong magnetic fields, magnetic field gradients, and ...

(MRI),

magnetic resonance angiography Magnetic resonance angiography (MRA) is a group of techniques based on magnetic resonance imaging (MRI) to image blood vessels. Magnetic resonance angiography is used to generate images of arteries (and less commonly veins) in order to evaluate ...

(MRA), or

computed tomography angiography Computed tomography angiography (also called CT angiography or CTA) is a computed tomography technique used for angiography—the visualization of arteries and veins—throughout the human body. Using contrast injected into the blood vessels, im ...

(CTA), which help visualize the blood vessels and detect abnormalities. Management of carotid artery dissection depends on the severity and symptoms. Treatment options often include medications like

anticoagulant An anticoagulant, commonly known as a blood thinner, is a chemical substance that prevents or reduces the coagulation of blood, prolonging the clotting time. Some occur naturally in blood-eating animals, such as leeches and mosquitoes, which ...

s or

antiplatelet An antiplatelet drug (antiaggregant), also known as a platelet agglutination inhibitor or platelet aggregation inhibitor, is a member of a class of pharmaceuticals that decrease platelet aggregation and inhibit thrombus formation. They are effectiv ...

agents to prevent blood clot formation and reduce the risk of stroke. In more severe cases, surgical or endovascular interventions, such as stenting or angioplasty, may be required to restore proper blood flow. Early detection and treatment are crucial for improving outcomes, though the prognosis can vary based on the extent of the dissection and the presence of complications.

Description

Carotid artery dissection (or cervical artery dissection) is the separation of the layers within the wall of the carotid arteries, which supply oxygen-rich blood to the brain. It is a significant cause of stroke in younger adults. The carotid arteries are major blood vessels in the neck that branch into smaller vessels called the external and internal carotid arteries. In carotid artery dissection, a tear in the arterial wall allows blood to flow between the layers of the artery, leading to potential narrowing, reduced blood flow, or clot formation, which may cause a stroke.

Signs and symptoms

The signs and symptoms of carotid artery dissection may be divided into

ischemic Ischemia or ischaemia is a restriction in blood supply to any tissue, muscle group, or organ of the body, causing a shortage of oxygen that is needed for cellular metabolism (to keep tissue alive). Ischemia is generally caused by problems ...

and non-ischemic categories: Non-ischemic signs and symptoms: * Neck pain and headache, sometimes escalating in intensity * Decreased pupil size with drooping of the upper eyelid ( Horner syndrome) *

Pulsatile tinnitus Tinnitus is a condition when a person hears a ringing sound or a different variety of sound when no corresponding external sound is present and other people cannot hear it. Nearly everyone experiences faint "normal tinnitus" in a completely ...

Ischemic signs and symptoms: * Temporary vision loss * Ischemic stroke

Causes

Dissection in ultrasound Dissection may occur after direct

physical trauma Injury is physiology, physiological damage to the living tissue of any organism, whether Injury in humans, in humans, Injury in animals, in other animals, or Injury in plants, in plants. Injuries can be caused in many ways, including mechanic ...

traffic collision A traffic collision, also known as a motor vehicle collision, or car crash, occurs when a vehicle collides with another vehicle, pedestrian, animal, road debris, or other moving or stationary obstruction, such as a tree, pole or building. Tr ...

strangulation Strangling or strangulation is compression of the neck that may lead to unconsciousness or death by causing an increasingly hypoxic state in the brain by restricting the flow of oxygen through the trachea. Fatal strangulation typically occurs ...

, or any phenomenon that causes hyperextension of the neck. They can also happen spontaneously. The causes of carotid artery dissection can be broadly categorized into two classes: spontaneous or traumatic. Dissection may occur after direct

, or any phenomenon that causes hyperextension of the neck. They can also happen spontaneously.

Spontaneous

Once considered uncommon, spontaneous carotid artery dissection is an increasingly recognized cause of stroke that preferentially affects the middle-aged. The incidence of spontaneous carotid artery dissection is low, and incidence rates for internal carotid artery dissection have been reported to be around 2.6 to 2.9 incidents per 100,000. Though the incidence is low, it is the cause of the vast majority of strokes in young people. Observational studies and case reports published since the early 1980s show that patients with spontaneous internal carotid artery dissection may also have a history of stroke in their family and/or hereditary connective tissue disorders, such as

Marfan syndrome Marfan syndrome (MFS) is a multi-systemic genetic disorder that affects the connective tissue. Those with the condition tend to be tall and thin, with dolichostenomelia, long arms, legs, Arachnodactyly, fingers, and toes. They also typically ha ...

, Ehlers-Danlos syndrome,

autosomal dominant polycystic kidney disease Autosomal dominant polycystic kidney disease (ADPKD) is one of the most common, life-threatening Genetic disorder, inherited human disorders and the most common hereditary kidney disease. It is associated with large interfamilial and intrafamilia ...

pseudoxanthoma elasticum Pseudoxanthoma elasticum (PXE) is a genetic disease that causes mineralization of elastic fibers in some tissues. The most common problems arise in the skin and eyes, and later in blood vessels in the form of premature atherosclerosis. PXE is cau ...

, fibromuscular dysplasia, and

osteogenesis imperfecta Osteogenesis imperfecta (; OI), colloquially known as brittle bone disease, is a group of genetic disorders that all result in bones that bone fracture, break easily. The range of symptoms—on the skeleton as well as on the body's other Or ...

type I. IgG4-related disease involving the carotid artery has also been observed as a cause. However, although an association with connective tissue disorders does exist, most people with spontaneous arterial dissections do not have associated connective tissue disorders. Also, the reports on the prevalence of hereditary connective tissue diseases in people with spontaneous dissections are highly variable, ranging from 0% to 0.6% in one study to 5% to 18% in another study. There is increasing evidence that internal carotid artery dissection can also be associated with the styloid process (known as Eagle syndrome when the elongated styloid process causes symptoms).

Traumatic

Carotid artery dissection is thought to be more commonly caused by severe violent trauma to the head and/or neck. An estimated 0.67% of patients admitted to the hospital after major motor vehicle accidents were found to have blunt carotid injury, including intimal dissections, pseudoaneurysms, thromboses, or fistulas. Of these, 76% had intimal dissections, pseudoaneurysms, or a combination of the two. Sports-related activities such as surfing and

Jiu-Jitsu Jujutsu ( , or ), also known as jiu-jitsu and ju-jitsu (both ), is a Japanese martial art and a system of close combat that can be used in a defensive or offensive manner to kill or subdue one or more weaponless or armed and armored opponent ...

have been reported as causes of carotid artery dissection. The probable mechanism of injury for most internal carotid injuries is rapid deceleration, with resultant hyperextension and rotation of the neck, which stretches the internal carotid artery over the upper

cervical vertebrae In tetrapods, cervical vertebrae (: vertebra) are the vertebrae of the neck, immediately below the skull. Truncal vertebrae (divided into thoracic and lumbar vertebrae in mammals) lie caudal (toward the tail) of cervical vertebrae. In saurop ...

, producing an intimal tear. After such an injury, the patient may remain asymptomatic, have a hemispheric transient ischemic event, or have a stroke. Artery dissection has also been reported in association with some forms of neck manipulation. There is significant controversy about the level of risk of stroke from neck manipulation. It may be that manipulation can cause dissection, or it may be that the dissection is already present in some people who seek manipulative treatment.

Pathophysiology

Arterial dissection of the carotid arteries is a condition that arises when a small tear forms in the innermost lining of the arterial wall, known as the

tunica intima The tunica intima (Neo-Latin "inner coat"), or intima for short, is the innermost tunica (biology), tunica (layer) of an artery or vein. It is made up of one layer of endothelium, endothelial cells (and macrophages in areas of disturbed blood flo ...

. This tear allows blood to enter the space between the inner and outer layers of the vessel, leading to either narrowing (

stenosis Stenosis () is the abnormal narrowing of a blood vessel or other tubular organ or structure such as foramina and canals. It is also sometimes called a stricture (as in urethral stricture). ''Stricture'' as a term is usually used when narrowing ...

) or complete occlusion. Notably, the stenosis in the early stages of arterial dissection is a dynamic process, and some occlusions can quickly transition back to stenosis. When complete occlusion occurs, it can result in ischemia, a condition characterized by insufficient blood supply to a particular area. In cases of complete occlusion, symptoms may not always be evident due to the presence of

collateral circulation Collateral circulation is the alternate Circulatory system, circulation around a blocked blood vessel, artery or vein via another path, such as nearby minor vessels. It may occur via preexisting vascular redundancy (analogous to redundancy (engi ...

, which helps to adequately perfuse the brain. However, complications can arise when blood clots develop at the site of the tear and subsequently break off, forming

emboli An embolism is the lodging of an embolus, a blockage-causing piece of material, inside a blood vessel. The embolus may be a blood clot (thrombus), a fat globule (fat embolism), a bubble of air or other gas ( gas embolism), amniotic fluid (amnio ...

. These emboli can then travel through the arteries and reach the brain, where they may block the blood supply. This blockage leads to an ischemic stroke, also known as a

cerebral infarction Cerebral infarction, also known as an ischemic stroke, is the pathologic process that results in an area of necrotic tissue in the brain (cerebral infarct). In mid to high income countries, a stroke is the main reason for disability among peo ...

. It is believed that blood clots or emboli originating from the dissection are responsible for causing infarctions in the majority of cases involving strokes in the presence of carotid artery dissection. Cerebral infarction, as a result of carotid artery dissection, can cause irreversible damage to the brain. Studies have demonstrated a significant number of patients with dissections go on to experience full blown strokes, often some time after the original dissection event. This emphasizes the serious and potentially life-altering consequences associated with this condition.

Treatment

The goal of treatment is to prevent the development of an actual stroke or limit the continuation of neurologic deficits should a stroke occur after dissection. Treatments include observation, anti-platelet agents,

anticoagulation An anticoagulant, commonly known as a blood thinner, is a chemical substance that prevents or reduces the coagulation of blood, prolonging the clotting time. Some occur naturally in blood-eating animals, such as leeches and mosquitoes, which h ...

stent In medicine, a stent is a tube usually constructed of a metallic alloy or a polymer. It is inserted into the Lumen (anatomy), lumen (hollow space) of an anatomic vessel or duct to keep the passageway open. Stenting refers to the placement of ...

implantation, carotid

endarterectomy Endarterectomy is a surgical procedure to remove the atheromatous ''plaque'' material, or blockage, in the lining of an artery constricted by the buildup of deposits. It is carried out by separating the plaque from the arterial wall. It was firs ...

, and carotid artery ligation.

Epidemiology

Carotid dissections events can occur at any age. They tend to occur more often in younger individuals under 50. Such events are slightly more common in men than in women. Spontaneous internal carotid artery dissection is a rare event with an incidence rate of approximately 2.6 to 2.9 per 100,000 individuals. However, such events account for ~5% to ~22% of strokes in patients under the age of 45 years.

References

External links

{{Vascular diseases Diseases of the aorta Vascular diseases Medical emergencies