Basic Lesions
The basic lesion in cervical artery dissection is an intramural haematoma in the vessel wall. This may occur as the result of two mechanisms:
- Haemorrhage from the vasa vasorum (Fig 1). The subsequent intramural haematoma can narrow the vessel lumen or cause an aneurysmal dilatation
- A tear in the intima of the vessel (Fig 2). This gives rise to an intimal flap and subsequent intra-vascular thrombosis
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| Fig 1: Haemorrhage from the vasa vasorum | Fig 2: Tear in the intima of the vessel with a blood clot at the site of the tear |