How useful is the 3-dimensional, surgeon's perspective-adjusted visualisation of the vessel anatomy during aneurysm surgery? A prospective clinical trial.

We hypothesized that neuronavigational 3-dimensional display of vessel and aneurysm anatomy, which is adjusted to the actual surgeon's view, could be helpful during the critical steps of aneurysm treatment. A total number of 32 patients with 42 aneurysms entered this prospective clinical trial. With a neuronavigational system, a 3-dimensional image of the arterial vascular anatomy was generated by autosegmentation of a computerized tomography (CT) angiographic data set. The 3-dimensional image was then adjusted to the surgeon's perspective by rotation. The neurosurgeon linked the 3-dimensional image information with the vascular structures in his surgical field by a neuronavigational pointer. He had the opportunity to further rotate the image with the displayed pointer for visualization of hidden structures. After operation, the neurosurgeon had to define with which expectations neuronavigation was applied and to evaluate if these expectations were fulfilled. The expectations with which the neurosurgeon used neuronavigation were to localize the aneurysm (n = 24), to understand the branching anatomy (n = 18), to visualize hidden structures (n = 8), to evaluate the projection of the aneurysm dome (n = 5) and to tailor the approach (n = 2). In 5 of the 42 aneurysms that were either very small or located in close vicinity to the skull base, the neurosurgeon's expectations were not fulfilled. A favorable outcome was achieved in 29 of the 32 patients (91%). Neuronavigational 3-dimensional display of the vessel anatomy was considered useful by the vascular neurosurgeon. Possibly, this technique has the potential to improve operative results by reduction of the surgical trauma and avoidance of intraoperative complications.