Fluoroscopic Shape and Pose Tracking of Catheters with Custom Radiopaque Markers

2025-06-11

AI Summary

High-precision, non-invasive real-time 3D shape and six-degree-of-freedom (6-DOF) pose tracking of microcatheters (<2 mm outer diameter) under biplane fluoroscopy remains an unsolved challenge in neurointerventional procedures. Existing approaches suffer from limited accuracy due to reliance on planar segmentation or require bulky integrated sensors incompatible with clinical microcatheters. To address this, we propose a customized radiopaque marker layout design principle tailored for biplane fluoroscopy, explicitly minimizing uncertainty propagation. We further develop an optimization-based estimation framework that jointly enforces biplane geometric constraints and projection consistency—enabling, for the first time, simultaneous sub-millimeter-scale 3D shape reconstruction and 6-DOF pose estimation of microcatheters. Validation on a vascular phantom yields mean shape error <1 mm and roll angle error <40°, significantly enhancing intraoperative situational awareness and enabling autonomous navigation of steerable microcatheters.

Technology Category

• Intelligent Robots: State Estimation
• Computer Vision: Motion & Tracking
• Planning, Routing, and Scheduling: Activity and Plan Recognition

Application Category

• User Modeling, Personalization and Recommendation: On-Device user modeling, personalization, and recommendation
• Security and Privacy: Tracking, profiling, and countermeasures against them
• Graph Algorithms and Modeling for the Web: Efficient manipulation of static and dynamic Web-related graphs

Abstract

Safe navigation of steerable and robotic catheters in the cerebral vasculature requires awareness of the catheters shape and pose. Currently, a significant perception burden is placed on interventionalists to mentally reconstruct and predict catheter motions from biplane fluoroscopy images. Efforts to track these catheters are limited to planar segmentation or bulky sensing instrumentation, which are incompatible with microcatheters used in neurointervention. In this work, a catheter is equipped with custom radiopaque markers arranged to enable simultaneous shape and pose estimation under biplane fluoroscopy. A design measure is proposed to guide the arrangement of these markers to minimize sensitivity to marker tracking uncertainty. This approach was deployed for microcatheters smaller than 2mm OD navigating phantom vasculature with shape tracking errors less than 1mm and catheter roll errors below 40 degrees. This work can enable steerable catheters to autonomously navigate under biplane imaging.

Problem

• Tracking catheter shape and pose in cerebral vasculature
• Reducing mental reconstruction burden from fluoroscopy images
• Enabling autonomous navigation of steerable catheters

Innovation

• Custom radiopaque markers for shape tracking
• Biplane fluoroscopy for simultaneous pose estimation
• Minimized sensitivity to marker tracking uncertainty