Carotid artery dissection after treadmill running.

The case is presented of carotid artery dissection causing Horner's syndrome in a 25 year old woman after treadmill running. She presented with characteristic eye signs and mild pain. Early diagnosis and treatment was associated with no long term, serious complications. It is now recognised that carotid artery dissection is more common than previously thought. Better imaging of the carotid artery has facilitated the diagnosis, and it is now essential to rule out this potentially fatal condition in patients presenting with postganglionic Horner's syndrome. It is accepted that relatively trivial trauma can cause a carotid artery dissection, and many sporting activities may place young, fit, healthy people at risk.