Carotid artery–hypoglossal nerve relationships in the neck: an anatomical work

Abstract

The relationship between the hypoglossal nerve and the carotid bifurcation is quite variable, and this explains the vulnerability of the nerve during carotid endarterectomy. The sternocleidomastoid artery is a good landmark for identifying the hypoglossal nerve. If there is exact anatomical knowledge about the relationship between the sternocleidomastoid artery and the hypoglossal nerve, the incidence of nerve injuries during carotid endarterectomy can be minimized.

The Unusual Origin of the Sternocleidomastoid Artery from the Lingual Artery

“…Among those injuries, hypoglossal nerve injuries were most common7). Even though the HN has various running courses in the neck, different landmarks have been proposed to recognize the level of the HN1-3,5,12,13,17,20). Characteristic vascular loop crossing over the HN is mainly made by the OA itself or the SCM artery originated from the OA.…”

“…Characteristic vascular loop crossing over the HN is mainly made by the OA itself or the SCM artery originated from the OA. The SCM artery as well as the occipital artery plays a role as a good landmark for the identification of the HN but the origin site of the SCM artery is not always consistent13). Antonius et al and Luis BF et al reported that the blood supply to the SCM muscle can be categorized into 3 parts : upper, middle, and lower8,11).…”

“…In 10% to 20% of cases, the LA shares a common trunk with the facial artery, typical from 4 branches : suprahyoid branch, dorsal lingual branch, deep lingual branch, and sublingual artery14). The LA also has various levels on the ECA13): average distance from the carotid bifurcation to the lingual artery was 9.99±6.60 mm on the right side and 12.63±8.36 mm on the left side. In total, 4 cases showed that the lingual artery was level with or lower than the carotid bifurcation13).…”

“…The LA also has various levels on the ECA13): average distance from the carotid bifurcation to the lingual artery was 9.99±6.60 mm on the right side and 12.63±8.36 mm on the left side. In total, 4 cases showed that the lingual artery was level with or lower than the carotid bifurcation13). In general, the LA is not a limiting factor in exposing the carotid bifurcation during carotid neck surgery.…”

“…Extracranial hypoglossal nerve injuries were not uncommon and occurred in 2-17% of cases7). The sternocleidomastoid (SCM) artery plays a role to identify the hypoglossal nerve during carotid neck surgery but its origin sites are various13). The aims of our research are to describe the SCM artery originated from the lingual artery and to review its clinical importance.…”