Efficient 3D Scene Reconstruction and Simulation from Sparse Endoscopic Views

Surgical simulation is essential for medical training, enabling practitioners to develop crucial skills in a risk-free environment while improving patient safety and surgical outcomes. However, conventional methods for building simulation environments are cumbersome, time-consuming, and difficult to scale, often resulting in poor details and unrealistic simulations. In this paper, we propose a Gaussian Splatting-based framework to directly reconstruct interactive surgical scenes from endoscopic data while ensuring efficiency, rendering quality, and realism. A key challenge in this data-driven simulation paradigm is the restricted movement of endoscopic cameras, which limits viewpoint diversity. As a result, the Gaussian Splatting representation overfits specific perspectives, leading to reduced geometric accuracy. To address this issue, we introduce a novel virtual camera-based regularization method that adaptively samples virtual viewpoints around the scene and incorporates them into the optimization process to mitigate overfitting. An effective depth-based regularization is applied to both real and virtual views to further refine the scene geometry. To enable fast deformation simulation, we propose a sparse control node-based Material Point Method, which integrates physical properties into the reconstructed scene while significantly reducing computational costs. Experimental results on representative surgical data demonstrate that our method can efficiently reconstruct and simulate surgical scenes from sparse endoscopic views. Notably, our method takes only a few minutes to reconstruct the surgical scene and is able to produce physically plausible deformations in real-time with user-defined interactions.