Cervical Artery Dissection

Aka: Cervical Artery Dissection, Cervicocerebral Arterial Dissection, Dissecting Aneurysm of Precerebral Artery, Cerebroarterial Dissection, Blunt Vertebral Vascular Injury, Blunt Cerebrovascular Injury

1. See Also
   1. Carotid Artery Dissection
   2. Traumatic Carotid Dissection
   3. Vertebral Artery Dissection
   4. Vertebral Artery Injury in Blunt Neck Trauma
2. Definitions
   1. Cervical Artery Dissection (Cervicocerebral Arterial Dissection)
      1. Extracranial Arterial Dissection includes carotid dissection and Vertebral Dissection
3. Epidemiology
   1. Cervical Artery Dissection (Carotid Artery and Vertebral Artery) are uncommon overall
      1. Overall: <2% of ischemic Cerebrovascular Accidents (2.6 to 2.9 per 100,000)
      2. Young Patients (age <45 years): 10-25% of ischemic Cerebrovascular Accidents
4. Pathophysiology
   1. Vessel intima tear or vasa vasorum rupture
   2. Vessel wall media develops localized bleeding
   3. Blood within vessel wall separates layers resulting in a false lumen
   4. Aneurysm may form if vessel wall Hematoma expands toward adventitia (sub-adventitial dissection)
   5. Vessel lumen may be narrowed if vessel wall expands towards intima
5. Types
   1. Carotid Artery Dissection (most common)
   2. Vertebral Artery Dissection
6. Risk Factors
   1. Genetic Predisposition, Typically Connective Tissue Disorder (spontaneous dissection)
      1. Ehlers-Danlos Syndrome Type IV
      2. Marfan's Syndrome
      3. Autosomal Dominant Polycystic Kidney Disease
      4. Osteogenesis Imperfecta Type 1
   2. Coronary Artery Disease Risk Factors
      1. Hypertension
      2. Atherosclerosis
   3. Other possible risk factors
      1. Migraine Headache with aura
      2. Respiratory infection
         1. Autumn peak in dissection Incidence also may suggest infectious contributing factors
7. Causes
   1. Spontaneous Cervical Artery Dissection
      1. Idiopathic (non-Traumatic)
      2. May be associated with risk factors as above
      3. Average age 44 years (+/- 13 years)
   2. Trauma
      1. See Vertebral Artery Injury in Blunt Neck Trauma
      2. See Traumatic Carotid Dissection
      3. Whiplash
      4. Rollercoasters
      5. Chiropractic Manipulation (1 in 20,000 Spinal Manipulations)
         1. Hufnagel (1999) Neurol 246: 683-88 [PubMed]
      6. Motor Vehicle Accidents (e.g. Seat Belt Sign)
      7. Strangulation Injury
   3. Hyperextension or rotation of the neck (esp. if sudden)
      1. Yoga
      2. Painting ceiling
      3. Coughing, Sneezing or Vomiting
      4. Procedural Sedation
8. Findings
   1. See Carotid Artery Dissection
   2. See Vertebral Artery Dissection
   3. Findings are specific to distribution of dissection
   4. Unilateral Headache (68%)
   5. Neck Pain (39%)
   6. Facial Pain (10%)
9. Differential Diagnosis
   1. See Headache Causes
   2. Subarachnoid Hemorrhage
   3. Cerebral Venous Thrombosis
   4. Reversible Cerebral Vasoconstriction Syndrome (RCBS)
   5. Spontaneous Intracranial Hypotension
   6. Pituitary Apoplexy
   7. Pheochromocytoma
   8. Cerebrovascular Accident
10. Imaging
    1. CT Angiogram Head and Neck
       1. Optimal in Vertebral Artery Dissection
       2. High efficacy when compared with DSA in blunt cervical Trauma
          1. Test Sensitivity: 97.7%
          2. Test Specificity: 100%
          3. Positive Predictive Value: 100%
          4. Negative Predictive Value: 99.3%
          5. Eastman (2006) J Trauma 60(5): 925-9 +PMID:16688051 [PubMed]
       3. Double lumen sign (false and true lumen)
       4. Flame-like taper of vessel lumen
    2. MRI/MRA Head and Neck (T1 axial cervical with fat saturation)
       1. Overall preferred dissection imaging, esp. in Carotid Artery Dissection
       2. Able to identify intramural Hematoma
    3. Digital Subtraction Angiography (DSA)
       1. Considered the gold standard, but invasive and CTA is typically performed instead
11. Complications
    1. Cerebrovascular Infarction (up to 70% of cases)
       1. Mechanisms
          1. Endothelial injury triggers the coagulation cascade with Thromboembolism (85% of cases)
          2. Vessel stenosis with watershed region ischemia
          3. Morel (2012) Stroke 43(5): 1354-61 [PubMed]
       2. May account for up to 20-25% of CVA in young patients <45 years old
       3. Typically occurs in the first 2 weeks of Cervical Artery Dissection
       4. CVA is more common in Vertebral Artery Dissection (esp. extracranial)
       5. Functional independence at 3 months in 75% of Cerebrovascular Accident cases
    2. Cerebral Vessel Stenosis (e.g. Carotid Artery Stenosis)
       1. Initially may be symptomatic
       2. Typically resolves in first 6 months
       3. Not associated with significant increased Cerebrovascular Accident risk after initial dissection
    3. Pseudoaneurysm
       1. Decreased risk of pseudoaneurysm enlargement with Antiplatelet Therapy and Anticoagulation
          1. Pseudoaneurysms completely resolve in 30% of cases
          2. Pseudoaneurysms persist but remain a stable size in 56% despite vessel otherwise healing
       2. Pseudoaneurysms enlarge in 13% cases and may become symptomatic
          1. Nonischemic Symptoms in 14% (Headache, Neck Pain, Cranial Nerve palsy, Horner Syndrome)
          2. Ischemic Symptoms in 3% (typically Transient Ischemic Attack; recurrent CVA is rare)
       3. Pseudoaneurysm risk of future rupture 1% (esp. intracranial vessels lacking external elastic lamina)
          1. Large pseudoaneurysms >10 mm diameter often undergo surgery (clipping or endovascular stent)
    4. Recurrent Cervical Artery Dissection
       1. Occurs in up to 7% of patients within 7 years
12. Management
    1. Consult Neurology and Neurosurgery
    2. Cerebrovascular Accident
       1. Systemic CVA Thrombolysis in acute CVA (<4.5 hours) as in non-dissection acute CVA (consult stroke neuro)
       2. In addition to CVA Thrombolytic Contraindications, Thrombolytics are also avoided in aortic arch involvement
       3. For NIHSS >=6 with persistent deficit, consider intervention (mechanical thrombectomy, Angioplasty, stenting)
    3. Antiplatelet Agents or Anticoagulation
       1. Management is controversial
       2. Aspirin may be as effective as Anticoagulation in Cervical Artery Dissection
          1. Markus (2015) Lancet 14:361-7 +PMID:25684164 [PubMed]
13. References
    1. Hussein and Leiman (2022) Crit Dec Emerg Med 36(8): 4-8
    2. Marcolini and Swaminathan in Herbert (2021) EM:Rap 21(3): 9-11
    3. Blum (2015) Arch Neurosci 2(4) +PMID:26478890 [PubMed]
    4. Shafafy (2017) J Spine Surg 3(20): 217-25 +PMID: 28744503 [PubMed]