Amended Intraoperative Neuronavigation; Novel 3-Dimensional Vascular Roadmapping with Superselective Angiographic Reconstructions

Aims: Three-dimensional digital subtraction angiography (3D-DSA) has not been fully utilized for neuronavigation purposes but carries certain advantages over MR or CT angiography. In particular, a superselective 3D-DSA can be done exclusively for a single vascular tree with superior vascular contrast enhancement thereby reducing imaging artifacts (e.g., embolization material) and resulting in a high resolution angio-anatomical profile of the vascular object of interest. When repeated intraoperatively, one can correct for brainshift and update neuronavigation accuracy. We introduce a technique that amends intraoperative vascular roadmapping accuracy by acquiring superselective 3D angiographic reconstructions with vascular object segmentation that can be uploaded in the neuronavigation system.

Methods: A superselective 3D digital subtracted angiography was acquired preoperatively with a wide field of view to include bony elements for accurate merging and registration within the neuronavigation software. Furthermore, a 3D vascular segmentation was done for the object of interest, which was subsequently uploaded into the neuronavigation software. These steps were repeated intraoperatively after acquiring an additional superselective DSA volume, thereby updating the neurovascular roadmap and neuronavigation accuracy (i.e. brainshift correction).

Results: This technique is illustrated in a subject undergoing elective microneurosurgical clipping of an ACOM Aneurysm in a state of the art hybrid neurosurgical operating setting.

Conclusion: Intraoperatively acquired superselective 3D angiographic vascular segmentations can provide an updated neurovascular roadmap by correcting for brainshift, thereby enhancing neuronavigation. This technique may greatly assist in intraoperative surgical re-orientation for deeply located AVM vessels, spinal dural AV fistulas, and peripheral or multiple intracranial aneurysms.