Vertebral Artery Dissection

Aka: Vertebral Artery Dissection, Vertebral Dissection, Vertebrobasilar Dissection

1. See Also
   1. Cerebrovascular Accident of Vertebral Artery
   2. Vertebral Artery Injury in Blunt Neck Trauma
2. Epidemiology
   1. Incidence: 1 to 1.5 per 100,000
   2. Cerebroarterial Dissections (Carotid Artery and Vertebral Artery) are uncommon (<2%) causes of Ischemic CVA
   3. Age
      1. Younger patients account for up to 25% of Vertebral Dissection related Ischemic CVA
      2. Peak Incidence age 50-60 years
   4. Gender
      1. Women are affected at a younger age than men
3. Pathophysiology
   1. Vertebral Artery media tear (middle muscular, arterial layer) allowing blood intrusion into arterial wall
      1. Resulting intramural thrombus occludes vessel with risk of CVA
4. Causes
   1. See Vertebral Artery Injury in Blunt Neck Trauma
   2. 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
   3. Hypertension or rotation of the neck (esp. if sudden)
      1. Yoga
      2. Painting ceiling
      3. Coughing, Sneezing or Vomiting
      4. Procedural Sedation
   4. Chiropractic Manipulation (1 in 20,000 Spinal Manipulations)
      1. Hufnagel (1999) Neurol 246: 683-88 [PubMed]
   5. Respiratory infection
      1. Autumn peak in dissection Incidence also may suggest infectious contributing factors
   6. Other possible risk factors
      1. Coronary Artery Disease Risk Factors
      2. Migraine Headache
5. Types
   1. Ischemic Vertebral Artery Dissection
      1. Resulting cerebral ischemia or infarction
      2. Many dissections heal spontaneously and occluded vessels may be compensated by opposite Vertebral Artery
   2. Rupture of Intradural Vertebral Artery dissecting aneurysm (hemorrhagic)
      1. Subarachnoid Hemorrhage
      2. Unstable with high risk of recurrent bleeding (70% of cases, most within first week, and mortality 47%)
6. Findings
   1. Extracranial Vertebral Artery Dissection (primarily at C1-2)
      1. Occipitocervical region severe pain
      2. Vertebrobasilar Ischemia or Infarction Symptom
         1. Dizziness
         2. Vertigo
         3. Diplopia
         4. Ataxia
         5. Dysarthria
      3. Vertebrobasilar Infarction
         1. Cerebellar infarction
         2. Wallenberg Syndrome
         3. Spinal Cord Infarction
   2. Intracranial Vertebral Artery Dissection
      1. Subarachnoid Hemorrhage in 50% of cases
      2. High rebleeding rate, poor prognosis, high mortality
      3. Responsible for up to 10% of non-Traumatic Subarachnoid Hemorrhage
      4. May be minor in some cases
7. Imaging
   1. MR Angiogram
      1. Has largely replaced CT Angiogram as gold standard, with similar efficacy
   2. CT Angiogram
      1. As with MRA, CT angiogram has high Test Sensitivity
8. Prognosis
   1. Extracranial Vertebral Artery Dissection
      1. No deficit 50%
      2. Mild deficit 21%
      3. Moderate to severe deficit 25%
      4. Mortality 4%
   2. Intracranial Vertebral Artery Dissection
      1. Associated with severe neurologic deficits
9. Management
   1. Anticoagulation (unless contraindicated, e.g. Hemorrhage)
      1. Intravenous Heparin, then
      2. Oral Anticoagulant
   2. Surgical interventions
      1. Endovascular procedures
      2. Vascular ot Neurosurgery
10. References
    1. Park (2008) J Korean Neurosurg Soc 44:109-15 [PubMed]