Evaluation of an electromagnetic 3D navigation system to facilitate endovascular tasks: a feasibility study.

INTRODUCTION

We describe a novel approach to arterial cannulation using the StealthStation(®) Guidance System (Medtronic, USA). This uses electromagnetic technology to track the guidewire, displaying a 3D image of the vessel and guidewire.

METHODS

The study was performed on a 'bench top' simulation model called the Cannulation Suite comprising of a silicone aortic arch model and simulated fluoroscopy. The accuracy of the StealthStation(®) was assessed. 16 participants of varying experience in performing endovascular procedures (novices: 6 participants, ≤5 procedures performed; intermediate: 5 participants, 6-50 procedures performed; experts: 5 participants, >50 procedures performed) underwent a standardised training session in cannulating the left subclavian artery on the model with the conventional method (i.e. with fluoroscopy) and with the StealthStation(®). Each participant was then assessed on cannulating the left subclavian artery using the conventional method and with the StealthStation(®). Performance was video-recorded. The subjects then completed a structured questionnaire assessing the StealthStation(®).

RESULTS

The StealthStation(®) was accurate to less than 1 mm [mean (SD) target registration error 0.56 mm (0.91)]. Every participant was able to complete the cannulation task with a significantly lower use of fluoroscopy with the navigation system compared with the conventional method [median 0 s (IQR 0-2) vs median 14 s (IQR 10-19), respectively; p = <0.001]. There was no significant difference between the StealthStation(®) and conventional method for: total procedure time [median 17 s (IQR 9-53) vs median 21 s (IQR 11-32), respectively; p=0.53]; total guidewire hits to the vessel wall [median 0 (IQR 0-1) vs median 0 (IQR 0-1), respectively; p=0.86]; catheter hits to the vessel wall [median 0.5 (IQR 0-2) vs median 0.5 (IQR 0-1), respectively; p=0.13]; and cannulation performance on the global rating scale [median score, 39/40 (IQR 28-39) vs 38/40 (IQR 33-40), respectively; p=0.40]. The intra-class correlation coefficient for agreement between video-assessors for all scores was 0.99. 88% strongly agreed that the StealthStation(®) can potentially decrease exposure of the patient to contrast and radiation.

CONCLUSION

Arterial cannulation is feasible with the StealthStation(®).