Central nervous system - Carotid an vertebral dissection

Question 1

Principle of disease regarding Carotid and Vertebral dissection

Answer 1

• Most frequent cause of stroke in patient <45 years old ( 20%)
• History associated with dissection include -:
  o Sudden neck movement
  o Trauma
  o Coughing
  o Minor fall
• Pathological lesion – intramural hemorrhage within the media of the arterial wall. This can be local or spread circumferentially and occlude the vessel.
• Distal embolization and platelet aggregation further complicate the condition.
• Timing of the CNS symptoms can be days to years

Question 2

What are the clinical presentations of Carotid dissection?

Answer 2

Classical triad -:
1) Unilateral headache – severe retro- orbital pain / throbbing headache with no history of cluster headache. – 50%
2) ipsilateral partial Horner’s syndrome
3) contra lateral hemispheric findings – aphasia, neglect, visual disturbance or hemi paresis
Warning symptoms – TIA, amaurosis fugax, syncope, episodic light headedness
- Factors associated with worse prognosis
o Old age
o Occlusive disease on angiography
o Stroke is the initial presentation

Question 3

What are the clinical presentations of the vertebral dissection

Answer 3

• less common
• relative young patient with
• severe unilateral posterior headache (67%) and
• neurological findings – weakness of arm , C5 or C6 nerve root
• symptoms rapidly developed i.e. cerebella and brain stem
  o vertigo
  o severe vomiting
  o ataxia
  o diplopia
  o hemi paresis
  o unilateral facial weakness
  o tinnitus
• around 10% died on the first presentation
• Good prognoses if patient survive.

Question 4

What are the diagnostic options employed?

Answer 4

• Angiography - gold standard but invasive
• MRI/MRA – replace angiography as gold standard
  o Dissection and hematoma in vessel wall
  o Irregular vascular margin
  o Filling defect
  o Extravasation of contrast
  o Caliber changes
  o Vascular occlusion
  o Intimal flaps
• Helical CT angiography
  o Similar result to MRI
  o Sensitivity approach 100%
  o Readily available
• US useful initially
  o Abnormal flow pattern >90% of patient with dissection

Question 5

What are the management’s options?

Answer 5

• Medical management
• stroke prevention ( anticoagulation/ Antiplatelet therapy)
• contraindicated if extend intracranial
• 90% of infarcts following dissection if thromboembolic rather than hemodynamic
• Most heal spontaneously
• Surgical management
• Reserved for patients with persistent ischemia despite adequate anticoagulation
• Ligation of the carotid/vertebral artery by-pass procedure or
• Endovascular stenting