Philippe Gailloud1, Ayushi Gautam2, Justin Caplan3. 1. Division of Interventional Neuroradiology, The Johns Hopkins Hospital, 1800 E Orleans Street, Baltimore, MD, 21287, USA. phg@jhmi.edu. 2. Division of Interventional Neuroradiology, The Johns Hopkins Hospital, 1800 E Orleans Street, Baltimore, MD, 21287, USA. 3. Department of Neurosurgery, The Johns Hopkins Hospital, 1800 E Orleans Street, Baltimore, MD, 21287, USA.
Abstract
PURPOSE: To report a case of unilateral segmental agenesis of the vertebral artery (VA). METHODS: We describe the angiographic and MRI features of a segmental VA agenesis (C2 segment). RESULTS: VA agenesis is caused by the absence of the anastomotic connection normally linking two adjacent intersegmental arteries; in the reported observation, a paravertebral extraforaminal anastomosis replaced the C2 segment normally joining the 1st and 2nd cervical intersegmental arteries through the C2 transverse foramen. CONCLUSION: We present an observation of segmental VA agenesis. This variant is consistent with the developmental history of the VA. It appears exceptional but is more likely underappreciated.
PURPOSE: To report a case of unilateral segmental agenesis of the vertebral artery (VA). METHODS: We describe the angiographic and MRI features of a segmental VA agenesis (C2 segment). RESULTS: VA agenesis is caused by the absence of the anastomotic connection normally linking two adjacent intersegmental arteries; in the reported observation, a paravertebral extraforaminal anastomosis replaced the C2 segment normally joining the 1st and 2nd cervical intersegmental arteries through the C2 transverse foramen. CONCLUSION: We present an observation of segmental VA agenesis. This variant is consistent with the developmental history of the VA. It appears exceptional but is more likely underappreciated.