  Medical steerable needles can follow 3D curvilinear trajectories inside body
tissue, enabling them to move around critical anatomical structures and
precisely reach clinically significant targets in a minimally invasive way.
Automating needle steering, with motion planning as a key component, has the
potential to maximize the accuracy, precision, speed, and safety of steerable
needle procedures. In this paper, we introduce the first resolution-optimal
motion planner for steerable needles that offers excellent practical
performance in terms of runtime while simultaneously providing strong
theoretical guarantees on completeness and the global optimality of the motion
plan in finite time. Compared to state-of-the-art steerable needle motion
planners, simulation experiments on realistic scenarios of lung biopsy
demonstrate that our proposed planner is faster in generating higher-quality
plans while incorporating clinically relevant cost functions. This indicates
that the theoretical guarantees of the proposed planner have a practical impact
on the motion plan quality, which is valuable for computing motion plans that
minimize patient trauma.
