Minor vessels leaving the extracranial internal carotid artery Possible clinical implications

Abstract

The microvascular anatomy of the internal carotid artery (ICA) was studied in a consecutive autopsy material consisting of 72 carotid arteries from 36 individuals. In 13 IC A's from 10 individuals 14 minor arteries with a calibre of 65 to 165 μm were found to leave the extracranial ICA lumen within 31 mm from the base of the skull. These vessels may contribute to the blood supply of the periadventitious sympathetic nerve plexus and explain the occurrence of a Horner's syndrome in disease of the ICA. Perhaps these vessels may also be relevant in the pathophysiology of unilateral deficits of lower cranial nerves with an acute onset.

Key Words:

• internal carotid artery
• vasa nervorum
• rete mirabile
• carotid sympathetic plexus
• lower cranial nerves
• Horner's syndrome
• jugular foramen syndrome
• carotid thrombosis
• dissecting carotid aneurysm