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arXiv · 2011.14298

A method for large diffeomorphic registration via broken geodesics

Alphin J. Thottupattu·Jayanthi Sivaswamy·Venkateswaran P. Krishnan
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Abstract

Anatomical variabilities seen in longitudinal data or inter-subject data is usually described by the underlying deformation, captured by non-rigid registration of these images. Stationary Velocity Field (SVF) based non-rigid registration algorithms are widely used for registration. SVF based methods form a metric-free framework which captures a finite dimensional submanifold of deformations embedded in the infinite dimensional smooth manifold of diffeomorphisms. However, these methods cover only a limited degree of deformations. In this paper, we address this limitation and define an approximate metric space for the manifold of diffeomorphisms $\mathcal{G}$. We propose a method to break down the large deformation into finite compositions of small deformations. This results in a broken geodesic path on $\mathcal{G}$ and its length now forms an approximate registration metric. We illustrate the method using a simple, intensity-based, log-demon implementation. Validation results of the proposed method show that it can capture large and complex deformations while producing qualitatively better results than the state-of-the-art methods. The results also demonstrate that the proposed registration metric is a good indicator of the degree of deformation.

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Alphin J. Thottupattu, Jayanthi Sivaswamy, Venkateswaran P. Krishnan. 2020-11-29. A method for large diffeomorphic registration via broken geodesics. https://arxiv.org/abs/2011.14298

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