High-resolution 3D Maps of Left Atrial Displacements using an Unsupervised Image Registration Neural Network

Christoforos Galazis, Anil Anthony Bharath, Marta Varela

Keywords: Left Atrial, Image Registration Neural Network, Displacement Field Vector

TL;DR: An image registration pipeline to extract plausible displacement field vectors from high-resolution 3D left atrium MRI scans

Abstract: Functional analysis of the left atrium (LA) plays an increasingly important role in the prognosis and diagnosis of cardiovascular diseases. Echocardiography-based measurements of LA dimensions and strains are useful biomarkers, but they provide an incomplete picture of atrial deformations. High-resolution dynamic magnetic resonance images (Cine MRI) offer the opportunity to examine LA motion and deformation in 3D, at higher spatial resolution and with full LA coverage. However, there are no dedicated tools to automatically characterise LA motion in 3D. Thus, we propose a tool that automatically segments the LA and extracts the displacement fields across the cardiac cycle. The pipeline is able to accurately track the LA wall across the cardiac cycle with an average Hausdorff distance of $2.51 \pm 1.3~mm$ and Dice score of $0.96 \pm 0.02$.