title: Diagnosis of a C3 segmental type of vertebral artery by magnetic resonance angiography: report of two cases.
abstract: We report two cases in which the vertebral artery (VA) entered the spinal canal via the intervertebral foramen at the C2-C3 disc level, an extremely rare variation regarded as a C3 segmental type of VA, that we diagnosed by magnetic resonance angiography. The C2 segmental type of VA, in which the VA enters the spinal canal via the C1-C2 intervertebral space, is relatively common. It is important to identify these variations before surgery of the craniovertebral junction or interventional procedures to prevent complications.
authors.affiliation: Department of Diagnostic Radiology, Saitama Medical University International Medical Center, 1397-1 Yamane, Hidaka, Saitama, 350-1298, Japan. auchino@saitama-med.ac.jp.
authors.forename: Akira
authors.initials: A
authors.lastname: Uchino
authors.affiliation: Department of Diagnostic Radiology, Saitama Medical University International Medical Center, 1397-1 Yamane, Hidaka, Saitama, 350-1298, Japan.
authors.forename: Naoko
authors.initials: N
authors.lastname: Saito
authors.affiliation: Department of Neurosurgery, Saitama Medical University International Medical Center, Hidaka, Japan.
authors.forename: Nahoko
authors.initials: N
authors.lastname: Uemiya
authors.affiliation: Department of Trauma and Emergency Acute Medicine, Saitama Medical University International Medical Center, Hidaka, Japan.
authors.forename: Ken-Ichiro
authors.initials: K
authors.lastname: Sonoda
mesh_terms: D000369:Aged, 80 and over; D063405:Anatomic Variation; D005260:Female; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D014711:Vertebral Artery / Q000033:anatomy & histology* / Q000000981:diagnostic imaging
keywords: C3 segmental type of VA; Cerebral arterial variation; Magnetic resonance angiography; Vertebral artery