Professor Ka-Wai Kwok of the Department of Mechanical Engineering and his team worked on the research for the topic “Interactive Multi-Stage Robotic Positioner for Intra-Operative MRI-Guided Stereotactic Neurosurgery”. The research findings were recently published in Advanced Science on December 10, 2023.
Details of the publication:
Interactive Multi-Stage Robotic Positioner for Intra-Operative MRI-Guided Stereotactic Neurosurgery
Zhuoliang He, Jing Dai, Justin Di-Lang Ho, Hon-Sing Tong, Xiaomei Wang, Ge Fang, Liyuan Liang, Chim-Lee Cheung, Ziyan Guo, Hing-Chiu Chang, Iulian Iordachita, Russell H. Taylor, Wai-Sang Poon, Danny Tat-Ming Chan, Ka-Wai Kwok, article in Advanced Science
https://onlinelibrary.wiley.com/doi/10.1002/advs.202305495
Abstract
Magnetic resonance imaging (MRI) demonstrates clear advantages over other imaging modalities in neurosurgery with its ability to delineate critical neurovascular structures and cancerous tissue in high-resolution 3D anatomical roadmaps. However, its application has been limited to interventions performed based on static pre/post-operative imaging, where errors accrue from stereotactic frame setup, image registration, and brain shift. To leverage the powerful intra-operative functions of MRI, e.g., instrument tracking, monitoring of physiological changes and tissue temperature in MRI-guided bilateral stereotactic neurosurgery, a multi-stage robotic positioner is proposed. The system positions cannula/needle instruments using a lightweight (203 g) and compact (Ø97 × 81 mm) skull-mounted structure that fits within most standard imaging head coils. With optimized design in soft robotics, the system operates in two stages: i) manual coarse adjustment performed interactively by the surgeon (workspace of ±30°), ii) automatic fine adjustment with precise (<0.2° orientation error), responsive (1.4 Hz bandwidth), and high-resolution (0.058°) soft robotic positioning. Orientation locking provides sufficient transmission stiffness (4.07 N/mm) for instrument advancement. The system's clinical workflow and accuracy is validated with lab-based (<0.8 mm) and MRI-based testing on skull phantoms (<1.7 mm) and a cadaver subject (<2.2 mm). Custom-made wireless omni-directional tracking markers facilitated robot registration under MRI.