Carotid artery dissection due to elongated styloid process: a self-stabbing phenomenon.

Elongated styloid process (ESP) is an anatomical variant that has been described as the cause of Eagle syndrome. Until recently, the styloid process has not been appreciated as a significant contributor to carotid artery dissection (CAD), which is not part of Eagle syndrome. We present a case of a 41-year-old male who presented with acute right middle cerebral artery occlusion and was found to have ESP projecting to and abutting the lateral wall of a dissected right internal carotid artery (ICA). Forced sustained head turning with maximal muscle contraction was the initiating event driving the styloid process into the wall of the ICA in a manner that can be likened to being stabbed with a pointed object. Knowing the association between ESP, Eagle syndrome, and CAD shall lead to increased awareness and appropriate diagnosis and treatment.