Fusion of Biplane Fluoroscopy With Fiber Bragg Grating for 3D Catheter Shape Reconstruction

Nowadays, navigating therapeutic catheters takes place under 2D fluoroscopic imaging. This requires considerable training of the clinician and exposes him/her to X-ray radiation. Researchers have increasingly investigated alternative sensing techniques. In this respect, Fiber Bragg Grating (FBG)-based shape sensing is gaining popularity. This letter proposes two approaches to fuse FBG with fluoroscropy, improve the understanding of the 3-dimensional shape while reducing fluoroscopy use. This letter proposes two FBG-fluoroscopy fusion approaches that combine fluoroscopy and FBG measurements. A comparison is performed between 3D shape reconstructions based on biplane fluoroscopy, rigidly fused multi-core FBG and dynamically fused FBG shape reconstruction. To verify the performance of the different approaches experiments were performed with custom made catheter in a CathLab on 3D printed tubes with known ground truth shape. The experiments showed overall acceptable errors for the targeted application with a maximum below 2 mm. The error of shape reconstruction through biplane fluoroscopy, rigid and dynamic fusion were found to be $1.51\pm 0.04$  mm, $1.77\pm 0.29$  mm and $1.47\pm 0.15$  mm, respectively. Thus, FBG-fluoroscopy fusion offers comparable results to fluoroscopy and may substantially reduce the radiation dose through optimal acquisition frequency.