Persistent hypoglossal artery versus type I proatlantal artery.

Abstract

I read with great interest the recent article titled ‘‘Left type I proatlantal artery with bilateral aberrant vertebral arteries and a ruptured aneurysm: a case report and review of the literature’’ by Tian et al. [3] published in Surgical and Radiologic Anatomy (2015;37:689–692). The type I proatlantal artery enters into the posterior fossa via the foramen magnum [2]. Reviewing Figs. 1b, c and 2e, I believe that this patient has persistent hypoglossal artery instead of type I proatlantal artery. Because, this anastomotic artery between the internal carotid artery and the vertebrobasilar system runs apparently at higher level than the foramen magnum, probably the hypoglossal canal, indicative of persistent hypoglossal artery [4]. Using the source images of CT angiography, the authors can show that this patient has whether persistent hypoglossal artery or type I proatlantal artery. Please show us the source images of the CT angiography for confirmation. In addition, the arrowheads in Fig. 1d may not indicate the hypoplastic vertebral artery but the deep cervical artery. The term ‘‘aberrant right vertebral artery’’ means anomalous right vertebral artery arising from the aortic arch distal to the left subclavian artery [1].