The vertebral artery: developmental pathology.

The vertebral artery (VA), whose embryogenesis is unique, different from that of any other vessel, is characterised by a great variety of malformations and anomalies. Some of the formers are truly pathological (that is symptomatic); the latter are just either anatomic or angiographic by chance findings. All of them should be kept in mind by the surgeon approaching the deep cervical and cranio-spinal regions, as well as by the interventional radiologist. Width and length anomalies of the VA, tortuosity and kinking, course anomalies, duplication and fenestration, persistence of primitive arteries, anomalies of collateral branches are discussed in the light of a literature review. Other pathologies of the cervical VA (spontaneous aneurysms and arteriovenous fistulae) associated exclusively with genetic diseases as neurofibromatosis type 1 (NF1) and fibro-muscular dysplasia (FMD) are also mentioned.