SRT-H: A Hierarchical Framework for Autonomous Surgery via Language Conditioned Imitation Learning

Research on autonomous robotic surgery has largely focused on simple task automation in controlled environments. However, real-world surgical applications require dexterous manipulation over extended time scales while demanding generalization across diverse variations in human tissue. These challenges remain difficult to address using existing logic-based or conventional end-to-end learning strategies. To bridge this gap, we propose a hierarchical framework for dexterous, long-horizon surgical tasks. Our method employs a high-level policy for task planning and a low-level policy for generating task-space controls for the surgical robot. The high-level planner plans tasks using language, producing task-specific or corrective instructions that guide the robot at a coarse level. Leveraging language as a planning modality offers an intuitive and generalizable interface, mirroring how experienced surgeons instruct traineers during procedures. We validate our framework in ex-vivo experiments on a complex minimally invasive procedure, cholecystectomy, and conduct ablative studies to assess key design choices. Our approach achieves a 100% success rate across n=8 different ex-vivo gallbladders, operating fully autonomously without human intervention. The hierarchical approach greatly improves the policy's ability to recover from suboptimal states that are inevitable in the highly dynamic environment of realistic surgical applications. This work represents the first demonstration of step-level autonomy, marking a critical milestone toward autonomous surgical systems for clinical studies. By advancing generalizable autonomy in surgical robotics, our approach brings the field closer to real-world deployment.

Towards Fluorescence-Guided Autonomous Robotic Partial Nephrectomy on Novel Tissue-Mimicking Hydrogel Phantoms

Autonomous robotic systems hold potential for improving renal tumor resection accuracy and patient outcomes. We present a fluorescence-guided robotic system capable of planning and executing incision paths around exophytic renal tumors with a clinically relevant resection margin. Leveraging point cloud observations, the system handles irregular tumor shapes and distinguishes healthy from tumorous tissue based on near-infrared imaging, akin to indocyanine green staining in partial nephrectomy. Tissue-mimicking phantoms are crucial for the development of autonomous robotic surgical systems for interventions where acquiring ex-vivo animal tissue is infeasible, such as cancer of the kidney and renal pelvis. To this end, we propose novel hydrogel-based kidney phantoms with exophytic tumors that mimic the physical and visual behavior of tissue, and are compatible with electrosurgical instruments, a common limitation of silicone-based phantoms. In contrast to previous hydrogel phantoms, we mix the material with near-infrared dye to enable fluorescence-guided tumor segmentation. Autonomous real-world robotic experiments validate our system and phantoms, achieving an average margin accuracy of 1.44 mm in a completion time of 69 sec.