Sports-related activities such as surfing and Jiu-Jitsu have been reported as causes of carotid artery dissection. The probable mechanism of injury for most internal carotid injuries is rapid deceleration, with resultant hyperextension and rotation of the neck, which stretches the internal carotid artery over the upper cervical vertebrae, producing an intimal tear. After such an injury, the patient may remain asymptomatic, have a hemispheric transient ischemic event, or have a stroke.Artery dissection has also been reported in association with some forms of neck manipulation. There is significant controversy about the level of risk of stroke from neck manipulation. It may be that manipulation can cause dissection, or it may be that the dissection is already present in some people who seek manipulative treatment. At this time, conclusive evidence does not exist to support either a strong association between neck manipulation and stroke, or no association. Pathophysiology
Arterial dissection of the carotid arteries occurs when a small tear forms in the innermost lining of the arterial wall (known as the tunica intima). Blood is then able to enter the space between the inner and outer layers of the vessel, causing narrowing (stenosis) or complete occlusion. The stenosis that occurs in the early stages of arterial dissection is a dynamic process and some occlusions can return to stenosis very quickly. When complete occlusion occurs, it may lead to ischaemia. Often, even a complete occlusion is totally asymptomatic because bilateral circulation keeps the brain well perfused.
Nevus of Ito (also known as "Nevus fuscoceruleus acromiodeltoideus") is a skin condition with similar features to the Nevus of Ota, but occurring in a different distribution. : 700

See also
Skin lesion

References


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