Comparative Study on Electromagnetic Tracking and Fiber Bragg Grating-based Catheter Shape Sensing

Shape sensing of flexible medical devices is receiving increased attention these days as it has the potential to offer clinicians improved guidance and help them to handle flexible instruments more easily during minimal invasive surgeries or interventions. Fiber optic-based shape sensing. e.g. via Fiber-Bragg Gratings (FBGs) is gaining popularity. Despite its high shape-sensing accuracy, fiber optic-based shape sensing methods often still requires extra position sensors, such as electromagnetic tracking (EMT), to localize the reconstructed shape with respect to a global reference frame. This can make the overall system complex and expensive. If EMTs are going to be used anyway, one wonders, if adding more EMTs could lead to an accuracy whereby the FBG can be omitted. This work hereto conducts a comparative study between an EMT-based and FBG-based shape sensing method. A fiber optic-based shape sensing method is implemented and compared with an EMT-only method. Static and dynamic experiments are carried out to verify the accuracy of the proposed method. The proposed EMT-based shape sensing method shows a mean error of approximately 7.1 mm (1.3%) for a sensed shape of 537 mm long catheter while that of the FBG-based method is 1.9 mm (0.45%).