Objectives: The purpose of this in vitro study was to clinically assess the feasibility of a three-dimensional (3D) electromagnetic (EM) navigator, including sensorized catheters and guidewires, to determine any reduction in radiation dose and contrast medium injection.Methods: The study was performed using a navigator prototype developed at the EndoCAS center. The system includes catheters and guidewires simultaneously tracked with an EM localizer (Aurora, Northern Digital, Waterloo, Canada). Tests were performed on a commercial abdominal aortic aneurysm model. Fifteen operators were asked to cannulate renal arteries using the conventional fluoroscopic guidance and the EM navigator without fluoroscopic support. Each trial was video-recorded and analyzed for timing and success of completing the cannulation task by two blinded and independent observers. Performances were also qualitatively evaluated using the Imperial College Endovascular Cannulation Scoring Tool (IC3ST). Moreover, a questionnaire was administered to participants to evaluate the navigator potentialities.Results: Quantitative analysis results show no significant difference between the fluoroscopic and EM guidance regarding the total procedure time (median 2.36 minutes [interquartile range {IQR} = 1.26-4.7) vs. 2.95 min [IQR = 1.35-5.38], respectively; p = .93); number of total hits with catheter/guidewire tip to vessels wall (median 5.50 [IQR = 2.00-10.00] vs. 3.50 [IQR = 2.50-7.00], respectively; p = .65); and number of attempts at cannulation (median 4.0 [IQR = 2.00-5.00] vs. 4.0 [IQR = 2.00-5.00], respectively; p = .72]. Moreover, there was no significant difference between the IC3ST score obtained using the EM navigator and the traditional method (average 22.37 [STD = 7.95] vs. 21.58 [STD = 6.86]; p = .92). Finally, questionnaire results indicate a general agreement concerning the navigator usefulness, which clearly shows the positions of instruments inside the 3D model of the patient's anatomy. Participants also agreed that the navigator can reduce the amount of contrast media delivered to the patient, as well as fluoroscopy time.Conclusions: This work provides proof of concept that simultaneous EM navigation of guidewires and catheters is feasible without the use of live fluoroscopic images. (C) 2013 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

BACKGROUND:Endovascular procedures are nowadays limited by difficulties arising from the use of 2D images and are associated with dangerous X-ray exposure and the injection of nephrotoxic contrast medium.METHODS:An electromagnetic navigator is proposed to guide endovascular procedures with reduced radiation dose and contrast medium injection. Five DOF electromagnetic sensors are calibrated and used to track in real time the positions and orientation of endovascular catheters and guidewires, while intraoperative 3D rotational angiography is used to acquire 3D models of patient anatomy. A preliminary prototype is developed to prove the feasibility of the system using an anthropomorphic phantom.RESULTS:The spatial accuracy of the system was evaluated during 70 targeting trials obtaining an overall accuracy of 1.2 ± 0.3 mm; system usability was positively evaluated by three surgeons.CONCLUSIONS:The strategy proposed to sensorize endovascular instruments paves the way for the development of surgical strategies with reduced radiation dose and contrast medium injection. Further in vitro, animal and clinical experiments are necessary for complete surgical validation.