EchoTracker: Advancing Myocardial Point Tracking in Echocardiography
Md Abulkalam Azad, Artem Chernyshov, John Nyberg, Ingrid Tveten, Lasse Lovstakken, Håvard Dalen, Bjørnar Grenne, Andreas Østvik
TL;DR
EchoTracker addresses the challenges of long-range myocardial tissue tracking in echocardiography by introducing a two-stage coarse-to-fine, TAP-inspired framework that jointly leverages coarse trajectory initialization and iterative refinement using multi-scale cost volumes. The method uses a lightweight pruned 2D encoder for coarse features, followed by a fine-stage with local multicrop-pyramid feature extraction and a 1D ResNet to update trajectories, enabling robust tracking across the cardiac cycle. Empirical results on four GE Vivid E95 datasets show EchoTracker outperforms state-of-the-art point-tracking methods in technical metrics and yields a 25% relative improvement in global longitudinal strain (GLS) measurements in a clinical test–retest setting. This approach offers a pathway to improved diagnostic and prognostic value in echocardiography and is made available as open-source code.
Abstract
Tissue tracking in echocardiography is challenging due to the complex cardiac motion and the inherent nature of ultrasound acquisitions. Although optical flow methods are considered state-of-the-art (SOTA), they struggle with long-range tracking, noise occlusions, and drift throughout the cardiac cycle. Recently, novel learning-based point tracking techniques have been introduced to tackle some of these issues. In this paper, we build upon these techniques and introduce EchoTracker, a two-fold coarse-to-fine model that facilitates the tracking of queried points on a tissue surface across ultrasound image sequences. The architecture contains a preliminary coarse initialization of the trajectories, followed by reinforcement iterations based on fine-grained appearance changes. It is efficient, light, and can run on mid-range GPUs. Experiments demonstrate that the model outperforms SOTA methods, with an average position accuracy of 67% and a median trajectory error of 2.86 pixels. Furthermore, we show a relative improvement of 25% when using our model to calculate the global longitudinal strain (GLS) in a clinical test-retest dataset compared to other methods. This implies that learning-based point tracking can potentially improve performance and yield a higher diagnostic and prognostic value for clinical measurements than current techniques. Our source code is available at: https://github.com/riponazad/echotracker/.
