The characteristics of patients with type 1: intraforaminal vertebral artery anomalies

Abstract

In a previous study, intraforaminal anomalies were found to occur at a rate of 7.6%. This increases the risk of injury to this vessel if the surgeon is unaware of such abnormalities preoperatively. The aim of our retrospective study was to identify patient factors that may predict anomalous intraforaminal vertebral arteries. Patient records were obtained from a previous study. In that study, the records of each consecutive patient who underwent cervical spine magnetic resonance imaging (MRI) for axial neck pain, radiculopathy, or myelopathy between January 2007 and January 2008 were reviewed. The social and medical histories of each patient were evaluated with respect to the presence or absence of an aberrant vertebral artery. We reviewed the medical records of the 250 patients whose MRIs were reviewed in the previous study. Seven patients were excluded for incomplete records. Chi-square and Fisher's exact tests were performed to compare the normal vertebral artery anatomy patients to the aberrant patients. The medical records of 19 patients with aberrant vertebral arteries and 224 patients with normal vertebral arteries were reviewed. The aberrant group was significantly older than the normal group (P=.00015). The only diagnostic condition that represented a statistically significant difference between the 2 groups was incidence of cancer. A relationship may exist between patient age, cancer, and medialization of the vertebral artery. The mechanism of this possible relationship is unclear. Although aberrant vertebral arteries are rare, a surgeon should have raised suspicion of this possibility in patients with a history of cancer.