Cervical Artery Dissection

• Thekrayat Khader, B.S.
• Mervat Nasry Wahba, M.D.

Definition

1. Tearing between the layers of the wall of an artery in the neck.

Synonyms

1. Carotid artery dissection

2. Vertebral artery dissection

ICD-10CM CODES
177.71	Dissection of carotid artery
177.74	Dissection of vertebral artery

Epidemiology & Demographics

The most common cervical artery dissection (CAD) is the internal carotid; the vertebral artery is less commonly affected. The tearing of the wall can cause clot formation, leading to stroke, especially in young patients. CAD can happen intracranially (most often) or extracranially (rare but worse prognosis).

Incidence

The average annual incidence rate for CAD is reported at 2.6 per 100,000 population; however, the true incidence is likely higher because many cases have self-limited clinical symptoms and remain undiagnosed.

Prevalence

Prevalence may reach 15% in the young adult stroke population.

Predominant Sex and Age

Carotid artery dissections are most commonly found in young adults. The mean age for extracranial internal carotid artery dissection is 40 years. Intracranial dissections are more common in those aged 20 to 30 years.

Genetics

Marfan syndrome, type IV Ehlers-Danlos syndrome, cystic medial necrosis, and the 677TT genotype of the 5,10-methylenetetrahydrofolate reductase gene (MTHFR 677TT) have been reported in association with CAD.

Risk Factors

1. •

   Seasonality: 58% more patients experience a cervical artery dissection during autumn (October)

2. •

   Vascular factors: hyperhomocysteinemia is strongly associated with CAD, especially if homocysteine levels are >12 micromols/L

3. •

   Chiropractic manipulations are often listed as risk factors, although evidence is lacking

4. •

   Major cervical trauma: hyperextension or rotation of the neck

5. •

   Although evidence is less strong, infection and migraine may also predispose to CAD, as well.

6. •

   Arterial wall intrinsic factors, such as arteriopathies, may predispose to arterial dissection after trivial trauma. Angiographic evidence of fibromuscular dysplasia has been noted in 10%-15% of patients.

Physical Findings & Clinical Presentation

A young adult with nuchal rigidity, neck pain, and severe occipital headache after minor head or neck trauma is a common presentation. Focal neurologic symptoms follow as a result of ischemia and may include:

1. •

   Ipsilateral facial pain and numbness: most common focal neurologic complaints

2. •

   Contralateral loss of pain and temperature sensation in the trunk and limbs

3. •

   Loss of taste, hiccups, vertigo, dysphagia, and unilateral hearing loss may also occur

4. •

   In contrast to younger patients, those over 60 rarely report mechanical triggers or pain

Pathophysiology

Arterial wall tears happen either spontaneously or as a result of minor trauma. The tear allows arterial blood under pressure to leak into the wall, creating either a hematoma or a false lumen. Sometimes the tear is subintimal, whereas other times it is subadventitial. Subintimal tears usually result in stenosis of the arterial lumen, whereas subadventitial dissection tends to cause arterial dilation.

Etiology

1. Cervical artery dissections may be spontaneous or traumatic. The majority of cases involve minor trauma.

    

Diagnosis

1. •

   Ultrasonography: safe and accurate; however, it has a 31% false negative result in patients with CAD presenting with Horner syndrome.

2. •

   CT angiography (Fig. 1)

   

3. •

   Conventional angiography

4. •

   MRA (Fig. 2) is the gold standard for diagnosis

   

Differential Diagnosis

1. •

   Cervical spine fracture

2. •

   Cluster headache

3. •

   Subarachnoid hemorrhage

4. •

   Hypoglycemia

5. •

   Stroke/TIA

6. •

   Migraine headache

7. •

   Other neck trauma

Workup

1. Labs not usually required except for determination of renal status for contrast use and coagulation panel. Obtaining blood products may also be necessary in cases of planned surgical intervention (type and cross/match).

2. Imaging studies such as ultrasound, conventional angiography, CT angiogram, or magnetic resonance angiography (MRA) give the ultimate diagnosis. The high false-negative rate in ultrasound limits its utility, and the high complication rate and unavailability of conventional angiography limit its widespread use.

Treatment/Management

1. •

   Cervical spine immobilization is the first step in the setting of any neck trauma.

2. •

   Initial noncontrast CT of the cervical spine should be ordered to rule out fracture if suspected; if negative, follow up with CT angiography or MRA.

3. •

   Anticoagulation therapy should be performed if there is no contraindication or high risk. First one must rule out intracranial hemorrhage and other bleeding source in trauma patients. Anticoagulation with heparin followed by warfarin is generally accepted as sufficient management for prevention of thromboembolic events.

4. •

   In the case of contraindications to anticoagulation therapy, antiplatelet therapy may be used.

5. •

   Do not use anticoagulation or antiplatelet therapy in a pregnant patient without an OB consultation.

Nonpharmacologic Therapy

Operative endovascular management with angioplasty or stent placement is only utilized in select patients. Criteria include:

1. •

   Persistent ischemic symptoms despite adequate anticoagulation

2. •

   Contraindication to anticoagulant therapy

3. •

   An iatrogenic dissection developing during an intravascular procedure

4. •

   Significantly compromised cerebral blood flow

Surgery has limited use in CAD, although surgical consultation is recommended.

Disposition

1. •

   Traumatic dissections: Admit to trauma unit with vascular service input.

2. •

   Spontaneous dissections: Admit to stroke service and potentially refer to vascular if endovascular intervention is recommended.

Referral

1. Vascular surgery

Complications

1. •

   Occlusion leading to ischemic stroke

2. •

   Thrombosis and embolization leading to TIAs

3. •

   Subarachnoid hemorrhage if the dissection is intracranial

4. •

   Pseudoaneurysm formation

Pearls & Considerations

1. In young patients with stroke-like symptoms or acute onset neck pain or headache, consider cervical artery dissection.

Suggested Readings

• C.A. Blum, et al.: Cervical artery dissection: a review of the epidemiology, pathophysiology, treatment, and outcome. Arch Neurosci. 2 (4):e26670 2015 26478890

• S. Debette, et al.: Cervical-artery dissections: predisposing factors, diagnosis and outcome. Lancet Neurol. 8 (7):668–678 2009 19539238

• Life in the Fast Lane Medical Blog: lifeinthefastlane.com/ccc/cervical-artery-dissection/

• C. Traenka, et al.: Cervical artery dissection patients ≥60 years: often painless, few mechanical triggers. Neurology. 88:1313–1320 2017 28258079