Yang, Xiaoxiao
Kolmogorov-Arnold Networks for Time Series Granger Causality Inference
Liu, Meiliang, Xu, Yunfang, Li, Zijin, Si, Zhengye, Yang, Xiaoxiao, Yang, Xinyue, Zhao, Zhiwen
We introduce Granger Causality Kolmogorov-Arnold Networks (GCKAN), an innovative architecture that extends the recently proposed Kolmogorov-Arnold Networks (KAN) to the domain of causal inference. By extracting base weights from KAN layers and incorporating the sparsity-inducing penalty along with ridge regularization, GCKAN infers the Granger causality from time series while enabling automatic time lag selection. Additionally, we propose an algorithm leveraging time-reversed Granger causality to enhance inference accuracy. The algorithm compares prediction and sparse-inducing losses derived from the original and time-reversed series, automatically selecting the casual relationship with the higher score or integrating the results to mitigate spurious connectivities. Comprehensive experiments conducted on Lorenz-96, gene regulatory networks, fMRI BOLD signals, and VAR datasets demonstrate that the proposed model achieves competitive performance to state-of-the-art methods in inferring Granger causality from nonlinear, high-dimensional, and limited-sample time series.
PDZSeg: Adapting the Foundation Model for Dissection Zone Segmentation with Visual Prompts in Robot-assisted Endoscopic Submucosal Dissection
Xu, Mengya, Mo, Wenjin, Wang, Guankun, Gao, Huxin, Wang, An, Li, Zhen, Yang, Xiaoxiao, Ren, Hongliang
Endoscopic Submucosal Dissection (ESD) is a surgical procedure employed in the treatment of early-stage gastrointestinal cancers [1, 2]. This procedure entails a complex series of dissection maneuvers that require significant skill to determine the dissection zone. In traditional ESD, a transparent cap is employed to retract lesions, which can often obscure the view of the submucosal layer and lead to an incomplete dissection zone. Conversely, our robot-assisted ESD [3] offers better visualization of the submucosal layer, resulting in a more completed dissection zone by utilizing robotic instruments that enable independent control over retraction and dissection. Achieving successful submucosal dissection requires the careful excision of the lesion or mucosal layer along with the complete submucosal layer while ensuring that both the underlying muscular layer and the mucosal surface remain unharmed. If the electric knife inadvertently contacts tissue outside the designated dissection area, it can lead to damage to the muscle layer, increasing the risk of perforations. Such complications not only elevate the surgical risks but can also complicate the patient's recovery. Therefore, it is imperative to maintain a precise dissection zone during endoscopic procedures. Effective guidance can help ensure that surgeons are adept at identifying and adhering to appropriate dissection boundaries and enhance the overall safety of endoscopic submucosal dissection (ESD).
ETSM: Automating Dissection Trajectory Suggestion and Confidence Map-Based Safety Margin Prediction for Robot-assisted Endoscopic Submucosal Dissection
Xu, Mengya, Mo, Wenjin, Wang, Guankun, Gao, Huxin, Wang, An, Bai, Long, Lyu, Chaoyang, Yang, Xiaoxiao, Li, Zhen, Ren, Hongliang
Robot-assisted Endoscopic Submucosal Dissection (ESD) improves the surgical procedure by providing a more comprehensive view through advanced robotic instruments and bimanual operation, thereby enhancing dissection efficiency and accuracy. Accurate prediction of dissection trajectories is crucial for better decision-making, reducing intraoperative errors, and improving surgical training. Nevertheless, predicting these trajectories is challenging due to variable tumor margins and dynamic visual conditions. To address this issue, we create the ESD Trajectory and Confidence Map-based Safety Margin (ETSM) dataset with $1849$ short clips, focusing on submucosal dissection with a dual-arm robotic system. We also introduce a framework that combines optimal dissection trajectory prediction with a confidence map-based safety margin, providing a more secure and intelligent decision-making tool to minimize surgical risks for ESD procedures. Additionally, we propose the Regression-based Confidence Map Prediction Network (RCMNet), which utilizes a regression approach to predict confidence maps for dissection areas, thereby delineating various levels of safety margins. We evaluate our RCMNet using three distinct experimental setups: in-domain evaluation, robustness assessment, and out-of-domain evaluation. Experimental results show that our approach excels in the confidence map-based safety margin prediction task, achieving a mean absolute error (MAE) of only $3.18$. To the best of our knowledge, this is the first study to apply a regression approach for visual guidance concerning delineating varying safety levels of dissection areas. Our approach bridges gaps in current research by improving prediction accuracy and enhancing the safety of the dissection process, showing great clinical significance in practice.
OSSAR: Towards Open-Set Surgical Activity Recognition in Robot-assisted Surgery
Bai, Long, Wang, Guankun, Wang, Jie, Yang, Xiaoxiao, Gao, Huxin, Liang, Xin, Wang, An, Islam, Mobarakol, Ren, Hongliang
In the realm of automated robotic surgery and computer-assisted interventions, understanding robotic surgical activities stands paramount. Existing algorithms dedicated to surgical activity recognition predominantly cater to pre-defined closed-set paradigms, ignoring the challenges of real-world open-set scenarios. Such algorithms often falter in the presence of test samples originating from classes unseen during training phases. To tackle this problem, we introduce an innovative Open-Set Surgical Activity Recognition (OSSAR) framework. Our solution leverages the hyperspherical reciprocal point strategy to enhance the distinction between known and unknown classes in the feature space. Additionally, we address the issue of over-confidence in the closed set by refining model calibration, avoiding misclassification of unknown classes as known ones. To support our assertions, we establish an open-set surgical activity benchmark utilizing the public JIGSAWS dataset. Besides, we also collect a novel dataset on endoscopic submucosal dissection for surgical activity tasks. Extensive comparisons and ablation experiments on these datasets demonstrate the significant outperformance of our method over existing state-of-the-art approaches. Our proposed solution can effectively address the challenges of real-world surgical scenarios. Our code is publicly accessible at https://github.com/longbai1006/OSSAR.