Hypoglossal artery and its clinical importance

Abstract

The hypoglossal artery is one of the carotid-basilar system anastomoses found in the embryonic period. It can be permanent in adulthood due to the failure of involuting vascular structures such as trigeminal, otic and interseg­mental arteries. Batujeff was the first one to describe this artery. Oertel suggested the name ‘`hypoglossal artery`` because the artery was following the hypoglossal nerve. When we examine its anatomical and clinical aspects, there are two forms of the hypoglossal artery: the embry­onic, or primitive form, is named primitive hypoglossal artery (PHA) and the persistent fetal, or adult form, is named persistent primitive hypoglossal artery (PPHA). When the embryo is 4 mm, PHA emerges as one of the presegmental branches of the dorsal aorta and serves as an anastomosis between the primitive internal carotid ar­tery and the bilateral longitudinal neural arteries. It disappears the embryo reaches a size between 5 and 6-mm, or between 7 and 12 mm, i.e. on the 29th day of gestation. Matsamura and Lindgren are the first to identify PPHA radiologically. There are several hypotheses about the topography of PPHA. In the presence of PPHA, various clinical associations such as, complications of head and neck surgery, aneu­rysms, subarachnoid hemorrhage and several syndromes can be observed.