A hybrid tracking system for image-guided spine surgery using a tracked mobile C-arm: a phantom study

Abstract

In recent years, an increasing number of various surgeries are observed utilizing fluoroscopy. The radiation exposure received by patients and medical staff and the surgical guidance in multiple planes frequently necessitate the positioning of a mobile C-arm. Operative navigation enables a mobile C-arm to provide multiplanar surgical guidance and decreases the radiation dose to the patient and operating room personnel. In this study, we propose a video-based tracked mobile C-arm (referred to as a "tracked C-arm system") to position the system. This system defines a reference framework to maintain the video-optical tracker data and computed tomography (CT) or cone-beam CT images' alignment as fine as possible despite patient or tracker movement. By employing our uniquely designed "six-facet" reference marker attached to the spine phantom, registration between the video-optical tracker and the spine phantom is maintained at arbitrary angles of the mobile C-arm. The tracked C-arm system provides a statistically significant improvement (P < 0.001) in target registration error in comparison with the conventional system: 0.80 $\pm $ 0.34 mm versus 1.60 $\pm $ 0.43 mm, respectively. The tracked C-arm system is designed to generate digitally reconstructed radiograph images from the mobile C-arm perspective, with projection error on the order of 0.74 $\pm $ 0.13 mm. Integration of the hybrid tracking system with mobile C-arm guidance has the capability to provide registration, reduce radiation exposure, and improve target registration accuracy.