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arXiv · 2506.15876

Tree-based adaptive finite element methods for deformable image registration

Nicolás A. Barnafi·Alberto F. Martın·Ricardo Ruiz-Baier
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Abstract

In this work we propose an adaptive Finite Element Method (FEM) formulation for the Deformable Image Registration problem (DIR) together with a residual-based a posteriori error estimator, whose efficiency and reliability are theoretically established. This estimator is used to guide Adaptive Mesh Refinement and coarsening (AMR). The nonlinear Euler-Lagrange equations associated with the minimisation of the relevant functional are solved with a pseudo time-stepping fixed-point scheme which is further accelerated using Anderson Acceleration (AA). The efficient implementation of these solvers relies on an efficient adaptive mesh data structure based on forests-of-octrees endowed with space-filling-curves. Several numerical results illustrate the performance of the proposed methods applied to adaptive DIR in application-oriented problems.

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Nicolás A. Barnafi, Alberto F. Martın, Ricardo Ruiz-Baier. 2025-06-18. Tree-based adaptive finite element methods for deformable image registration. https://arxiv.org/abs/2506.15876

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