J Korean Soc Magn Reson Med.  2013 Mar;17(1):55-58. 10.13104/jksmrm.2013.17.1.55.

Persistent Proatlantal Artery in Magnetic Resonance Angiography: A Case Report

• Jeon SW
• Chang HW
• Kim MJ
• Cho J

• KMID: 1426753
• DOI: http://doi.org/10.13104/jksmrm.2013.17.1.55

Abstract

Persistent proatlantal artery (PPA) is a rare embryologically remnant carotico-vertebrobasilar anastomoses. There are two types of PPA according to embryological considerations, origin and anatomic course. Type I PPA usually originate from internal carotid artery and not traversing transverse foramen. Type II PPA traverses from external carotid artery to C1 transverse foramen. The PPA is usually found incidentally without clinical symptoms, but can be related to several clinically significant vascular lesions, such as hypoplastic vertebral artery, intracranial arteriovenous malformation and in a case of carotid endarterectomy or external carotid artery embolization. So, thorough understanding of this anomaly is needed and we report a case of type II PPA diagnosed by MR angiography.

Keyword

Proatlantal artery Type II; Carotico-vertebrobasilar anastomosis; Magnetic resonance angiography (MRA)

MeSH Terms

Angiography
Arteries
Carotid Artery, External
Carotid Artery, Internal
Endarterectomy, Carotid
Intracranial Arteriovenous Malformations
Magnetic Resonance Spectroscopy
Magnetics
Magnets
Vertebral Artery

Figure

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  Fig. 1 Contrast-enhanced neck MR angiography. Left oblique view (a) and posterior-anterior view (b) shows Type II proatlantal artery which originate from left proximal ECA (arrow). This artery traverses from left proximal ECA to left vertebral artery ,V3 segment (arrow heads). There is aplasia of left vertebral artery involving V1 and V2 segments.

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  Fig. 2 Brain TOF (time-of flight) MR angiography shows about 2 mm sized small aneurysm of the right paraclinoid internal carotid artery (arrow).

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