Dissection of the intracranial internal carotid artery producing isolated oculomotor nerve palsy with sparing of pupil.

Dissection of the internal carotid artery usually occurs in the cervical segment, but rarely may involve the artery in the intracranial course (1). The clinical course of intracranial dissection is often catastrophic, with rapid onset of profound neurological deficit, as a result of middle and/or anterior cerebral artery involvement. When this occurs the mortality rate is generally considered high. We describe a case of intracranial internal carotid artery dissection following trivial trauma presented with an isolated painful pupillary sparing oculomotor nerve palsy.