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arXiv · 2408.13699

SeeBelow: Sub-dermal 3D Reconstruction of Tumors with Surgical Robotic Palpation and Tactile Exploration

Raghava Uppuluri·Abhinaba Bhattacharjee·Sohel Anwar·Yu She
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Abstract

Surgical scene understanding in Robot-assisted Minimally Invasive Surgery (RMIS) is highly reliant on visual cues and lacks tactile perception. Force-modulated surgical palpation with tactile feedback is necessary for localization, geometry/depth estimation, and dexterous exploration of abnormal stiff inclusions in subsurface tissue layers. Prior works explored surface-level tissue abnormalities or single layered tissue-tumor embeddings with more than 300 palpations for dense 2D stiffness mapping. Our approach focuses on 3D reconstructions of sub-dermal tumor surface profiles in multi-layered tissue (skin-fat-muscle) using a visually-guided novel tactile navigation policy. A robotic palpation probe with tri-axial force sensing was leveraged for tactile exploration of the phantom. From a surface mesh of the surgical region initialized from a depth camera, the policy explores a surgeon's region of interest through palpation, sampled from bayesian optimization. Each palpation includes contour following using a contact-safe impedance controller to trace the sub-dermal tumor geometry, until the underlying tumor-tissue boundary is reached. Projections of these contour following palpation trajectories allows 3D reconstruction of the subdermal tumor surface profile in less than 100 palpations. Our approach generates high-fidelity 3D surface reconstructions of rigid tumor embeddings in tissue layers with isotropic elasticities, although soft tumor geometries are yet to be explored.

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Raghava Uppuluri, Abhinaba Bhattacharjee, Sohel Anwar, Yu She. 2024-08-25. SeeBelow: Sub-dermal 3D Reconstruction of Tumors with Surgical Robotic Palpation and Tactile Exploration. https://arxiv.org/abs/2408.13699

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