[Painful Horner's syndrome revealing carotid artery dissection : about four cases].

We report four cases of painful Horner's syndrome due to carotid artery dissection. A lesion on oculosympathic pathway causes Horner's syndrome. A painful Horner's syndrome needs a prompt exploration by tomodensitometry or magnetic resonance imaging to exclude carotid artery dissection. Actually, carotid artery dissection leads to stroke or cerebral ischemic symptoms, mainly in the first two weeks. The treatment is based on anticoagulants or antiplatelet agents.