cs.CVSep 13, 2026

S3-Tracker: Self-Supervised Surgical Tissue Tracking With Contrastive Random Walks

Authors: Jiaming Zhang, Zijian Wu, Mehran Armand, Septimiu Salcudean

Organizations: Department of Computer Science, Johns Hopkins University · Robotics and Control Laboratory, The University of British Columbia · The Institute for Integrative and Innovative Research, University of Arkansas

Abstract

Robust point tracking in endoscopic videos is essential for computer-assisted intervention and autonomous robotic surgery, enabling continuous registration between intraoperative video and preoperative imaging despite soft tissue deformation. However, supervised tracking methods depend on large annotated datasets, while surgical conditions make reliable trajectory annotation challenging. We propose a self-supervised Track-Any-Point approach that learns from unlabeled surgical videos by establishing global pixel correspondences and inferring point trajectories through contrastive random walks. Trained without annotations, our method achieves performance comparable to existing semi-supervised approaches while implicitly handling tissue deformation. These findings demonstrate the feasibility of self-supervised point tracking in surgical environments and its potential to reduce reliance on annotated data.

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