Single Image Estimation of Cell Migration Direction by Deep Circular Regression
Lennart Bruns, Lucas Lamparter, Milos Galic, Xiaoyi Jiang
TL;DR
This work tackles estimating cell migration direction from a single image (SIECMD) using deep circular regression to respect angular data. It systematically evaluates encoding, activation, and loss configurations with a probing CNN, selects circle encoding with activation $\varphi_{sigmoid2d}$ and loss $\delta_{dist}^2$, and then fine-tunes EfficientNetV2 with ImageNet pretraining, incorporating test-time augmentation. On NIH3T3, U373, and MS3T3 datasets, the method achieves mean angular deviations of approximately $17^\circ$ on NIH3T3 and U373 and around $30^\circ$ on MS3T3, significantly outperforming Nishimoto2019's $30^\circ$–$34^\circ$ results. The work enables high-throughput, tracking-free analyses in cell migration and points to future extensions to more datasets and real-world workflows.
Abstract
In this paper, we address the problem of estimating the migration direction of cells based on a single image. A solution to this problem lays the foundation for a variety of applications that were previously not possible. To our knowledge, there is only one related work that employs a classification CNN with four classes (quadrants). However, this approach does not allow for detailed directional resolution. We tackle the single image estimation problem using deep circular regression, with a particular focus on cycle-sensitive methods. On two common datasets, we achieve a mean estimation error of $\sim\!17^\circ$, representing a significant improvement over previous work, which reported estimation error of $30^\circ$ and $34^\circ$, respectively.
