Internal Trapping of a Symptomatic Unruptured Giant Vertebral Artery Aneurysm Using the Coiling-in-bridging-stent Technique: A Case Report

Objective: We report a patient in whom a devised stent-assisted internal trapping was effective to eliminate the mass effect of a symptomatic giant vertebral artery (VA) aneurysm. Case Presentation: A 63-year-old female. Detailed examination of gait disorder showed a brainstem-compressing, nonthrombotic, giant, fusiform aneurysm at an area distal to the posterior inferior cerebellar artery (PICA) bifurcation of the left VA. Endovascular internal trapping was planned, but the exacerbation of mass effects related to the coils inserted into the aneurysm cavity was concerned. Thus, before the usual internal trapping procedure, a self-expanding stent was deployed across the aneurysm to limit the coils in the stent during the internal trapping procedure. Six months later, the aneurysm decreased markedly in size with a complete relief of neurological symptom. Conclusion: Our devised stent-assisted internal trapping method, coiling-in bridging-stent technique, was successful to exclude a symptomatic giant VA aneurysm from the circulation with a minimum amount of coil in the aneurysm cavity. With this method, marked decrease in size could be expected since coils would not interfere with the shrinkage of the aneurysm. This method would be useful in giant cerebral aneurysms which need endovascular internal trapping.