Real-Time 3D Instrument Tip Tracking Using 2D X-ray Fluoroscopy with Vessel Deformation Correction under Free Breathing

Accurate localization of the instrument tip within the hepatic vein is crucial for the success of transjugular intrahepatic portosystemic shunt (TIPS) procedures. Real-time tracking of the instrument tip in X-ray images is greatly influenced by vessel deformation due to patient's pose variation, respiratory motion, and puncture manipulation, frequently resulting in failed punctures. We propose a novel framework called deformable instrument tip tracking (DITT) to obtain the real-time tip positioning within the 3D deformable vasculature. First, we introduce a pose alignment module to improve the rigid matching between the preoperative vessel centerline and the intraoperative instrument centerline, in which the accurate matching of 3D/2D centerline features is implemented with an adaptive point sampling strategy. Second, a respiration compensation module using monoplane X-ray image sequences is constructed and provides the motion prior to predict intraoperative liver movement. Third, a deformation correction module is proposed to rectify the vessel deformation during procedures, in which a manifold regularization and the maximum likelihood-based acceleration are introduced to obtain the accurate and fast deformation learning. Experimental results on simulated and clinical datasets show an average tracking error of 1.59 0.57 mm and 1.67 0.54 mm, respectively. Our framework can track the tip in 3D vessel and dynamically overlap the branch roadmapping onto X-ray images to provide real-time guidance. Accurate and fast (43ms per frame) tip tracking with the proposed framework possesses a good potential for improving the outcomes of TIPS treatment and minimizes the usage of contrast agent.