Eagle Syndrome and Internal Carotid Artery Dissection: Description of Five Cases Treated in Two Italian Institutions and Review of the Literature.

Eagle syndrome is a rare pattern of symptoms (0.16% of the general population) due to the conflict with adjacent anatomical structures by an elongated styloid process or a calcified stylohyoid ligament; 2 variants of this condition have been described in the literature, classical and vascular. The classical form is caused by compression of the glossopharyngeal nerve and the surrounding structures from an abnormal stylohyoid apparatus, causing odynophagia and neck pain and is usually treated by an otorhinolaryngologist. The vascular form, determined by the conflict between the osteoligamentous malformation and the extracranial carotid artery, can cause neurological symptoms due to the compression of the vessel or in some cases the dissection of the carotid artery itself. However, an elongated styloid process occurs in about 4% of the general population, and the most recent literature shows that the vascular form of Eagle syndrome could be an underestimated cause of carotid artery dissection (CAD) and should be considered in the differential diagnosis of this condition. In addition to the literature many different treatment options for this condition are reported, either medical and/or surgical, but an ideal approach has not yet been fully identified. We report 5 cases of internal CAD due to the vascular variant of Eagle syndrome treated in 2 different Italian institutions (Department of Vascular and Endovascular Surgery, Galliera Hospital, Genoa and Department of Vascular Surgery, Santi Filippo e Nicola Hospital, Avezzano, L'Aquila) and a careful and analytical review of the available literature on this topic.