Planning Nonlinear Access Paths for Temporal Bone Surgery

TL;DR

This paper introduces fast, accurate nonlinear path planning methods for temporal bone surgery, improving safety and outcomes by optimizing trajectories around sensitive structures using advanced motion planning algorithms.

Contribution

The paper presents novel k-RRT-Connect algorithms tailored for nonlinear surgical path planning in SE(3), outperforming existing methods in accuracy and computational efficiency.

Findings

k-RRT-Connect outperforms state-of-the-art methods in real patient data

Algorithms achieve faster planning times suitable for intra-operative use

Demonstrated improved safety margins in simulated surgical trajectories

Abstract

Purpose: Interventions at the otobasis operate in the narrow region of the temporal bone where several highly sensitive organs define obstacles with minimal clearance for surgical instruments. Nonlinear trajectories for potential minimally-invasive interventions can provide larger distances to risk structures and optimized orientations of surgical instruments, thus improving clinical outcomes when compared to existing linear approaches. In this paper, we present fast and accurate planning methods for such nonlinear access paths. Methods: We define a specific motion planning problem in SE(3) = R3 x SO(3) with notable constraints in computation time and goal pose that reflect the requirements of temporal bone surgery.We then present k-RRT-Connect: two suitable motion planners based on bidirectional Rapidly-exploring Random Trees (RRT) to solve this problem efficiently. Results: The benefits of k-RRT-Connect are demonstrated on real CT data of patients. Their general performance is shown on a large set of realistic synthetic anatomies. We also show that these new algorithms outperform state of the art methods based on circular arcs or Bezier-Splines when applied to this specific problem. Conclusion: With this work we demonstrate that pre- and intra-operative planning of nonlinear access paths is possible for minimally-invasive surgeries at the otobasis.