Anomalous vertebral and posterior communicating arteries as a risk factor in instrumentation of the posterior cervical spine

Abstract

We investigated the incidence of anomalies in the vertebral arteries and Circle of Willis with three-dimensional CT angiography in 55 consecutive patients who had undergone an instrumented posterior fusion of the cervical spine. We recorded any peri-operative and post-operative complications. The frequency of congenital anomalies was 30.9%, abnormal vertebral artery blood flow was 58.2% and vertebral artery dominance 40%. The posterior communicating artery was occluded on one side in 41.8% of patients and bilaterally in 38.2%. Variations in the vertebral arteries and Circle of Willis were not significantly related to the presence or absence of posterior communicating arteries. Importantly, 18.2% of patients showed characteristic variations in the Circle of Willis with unilateral vertebral artery stenosis or a dominant vertebral artery, indicating that injury may cause lethal complications. One patient had post-operative cerebellar symptoms due to intra-operative injury of the vertebral artery, and one underwent a different surgical procedure because of insufficient collateral circulation. Pre-operative assessment of the vertebral arteries and Circle of Willis is essential if a posterior spinal fusion with instrumentation is to be carried out safely.

Unilateral and Bilateral Aplasia of the Anterior Cerebral Artery in the Presence of Their Vascular Sources

“…In Serbia, Ješić et al [19] discovered A1 aplasia in 2.9% of the angiograms of 1000 patients with different pathology; however we found 0.51% of (unilateral and bilateral) ACA aplasia in cadavers autopsied due to different reasons and pathology as well. In Japan, Wanibuchi et al [54] discovered 11.1% of A1 aplasia among nine patients with the ACA aneurysms, whereas Uchino et al [47] recorded 50/891 (5.6%) the patients with A1 aplasia suspected to suffer from cerebrovascular disease, while Nagahama et al [34] recorded 3.6% of A1 aplasia among the 55 patients hospitalized because of the instrumentation of the posterior cervical spine. In addition, Uchino et al [47] found a higher frequency of aplasia of the right ACA (31) vs. the left ACA (19) aplasia in Japanese population.…”

Variations of transverse foramina in cervical vertebrae: what happens to the vertebral artery?

“…During anterior corpectomy, excessive lateral body resection is a risk factor for the integrity of the vertebral artery [32], and a duplication or triplication of the foramen, with or without a multiple artery lumen, could disorientate the surgeon. In posterior procedures, such as lateral mass and pedicle screw fixation, there is also a risk of injury [32,33]. An aberrant course of the artery may cause an arterial injury during the screw placement and this may be clinically important if the contralateral artery is hypoplastic (Fig.…”

Delayed bilateral vertebral artery occlusion after cervical spine injury: a case report

“…[8][9][10][11] These cases will result in brain-stem infarction that can be fatal if the vertebral artery is occluded. Therefore, it should be considered that reflow of the vertebral artery has great benefit, and it should not be considered that no issues will occur, although the screws perforated only because the vertebral artery is already occluded.…”