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arXiv · 2206.10616

Bioelectric Registration of Electromagnetic Tracking and Preoperative Volume Data

Abstract

For minimally invasive endovascular surgery, the localization of catheters and guidewires inside the human body is essential. Electromagnetic (EM) tracking is one technology that allows localizing such surgical instruments. For localizing intra-operatively EM-tracked instruments with respect to preoperative volume data, it is necessary to bring pre- and intraoperative imaging into the same coordinate frame. In most existing solutions, such registration requires additional interactions, modifying the procedure's original workflow. We propose a new method taking advantage of Bioelectric signals to initialize and register preoperative volumes to the EM tracking system without significantly changing the interventional workflow. We envision the most natural use-case of our concept in cardiac electrophysiology (EP) procedures, in which EP catheters are already equipped with all the necessary sensing, including electric sensing for the measurement of electrophysiological signals and EM tracking for catheter localization. We use EP catheters for Bioelectric sensing to detect local features of the vasculature while advancing the catheter inside the human body. Such features can be automatically labeled before the procedure within the preoperative data. The combination of Bioelectric and EM tracking can localize vascular features such as bifurcations and stenosis within the EM tracking space. Mapping them to preoperative data automatically registers patients' CT space to EM tracking. The proposed registration process is entirely based on Bioelectric sensed features, with no need for external markers or other interventional imaging devices.

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Ardit Ramadani, Heiko Maier, Felix Bourier, Christian Meierhofer, Peter Ewert, Heribert Schunkert, Nassir Navab. 2022-06-20. Bioelectric Registration of Electromagnetic Tracking and Preoperative Volume Data. https://arxiv.org/abs/2206.10616

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