¤EXPERIMENTAL INVESTIGATION ¤ Three-Dimensional Endovascular Navigation With Electromagnetic Tracking: Ex Vivo and In Vivo Accuracy

Purpose: To evaluate the accuracy of a 3-dimensional (3D) navigation system using electromagnetically tracked tools to explore its potential in patients. Methods: The 3D navigation accuracy was quantified on a phantom and in a porcine model using the same setup and vascular interventional suite. A box-shaped phantom with 16 markers was scanned in 5 different positions using computed tomography (CT). The 3D navigation system registered each CT volume in the magnetic field. A tracked needle was pointed at the physical markers, and the spatial distances between the tracked needle positions and the markers were calculated. Contrast-enhanced CT images were acquired from 6 swine. The 3D navigation system registered each CT volume in the magnetic field. An electromagnetically tracked guidewire and catheter were visualized in the 3D image and navigated to 4 specified targets. At each target, the spatial distance between the tracked guidewire tip position and the actual position, verified by a CT control, was calculated. Results: The mean accuracy on the phantom was 1.2860.53 mm, and 90 % of the measured distances were #1.90 mm. The mean accuracy in swine was 4.1861.76 mm, and 90 % of the measured distances were #5.73 mm. Conclusion: This 3D navigation system demonstrates good ex vivo accuracy and is sufficiently accurate in vivo to explore its potential for improved endovascular navigation. J Endovasc Ther. 2011;18:230–240 Key words: electromagnetic tracking, navigation, endovascular aneurysm repair, abdom