Hong Kong researchers design soft robot for microsurgery
The system was designed by Dr Kwok Ka Wai of the Department of Mechanical Engineering, University of Hong Kong and Dr Jason Chan of the Faculty of Medicine, Chinese University of Hong Kong. Dr Kwok is a Croucher scholar (Croucher Fellowship, Harvard University and University of Georgia, 2013).
Image-guided laser ablation is a minimally invasive approach for the treatment of head and neck cancers. Robotic systems can help surgeons to achieve more precise results, however, traditional robots with metallic components cannot be used within magnetic resonance imaging (MRI) machines due to the strong magnetic field.
The hydraulically actuated soft robotic manipulator designed by Kwok and Chan allows safe and accurate laser ablation while utilising MRI for real-time and precise monitoring of tissue ablation margin and thermal diffusion.
The device has a diameter of less than 12 millimetres and weighs 100 grammes. It has five degrees of freedom of movement and is 3D printed with both soft and hard structures to improve stiffness and responsiveness.
The system produces zero electromagnetic interference, enabling the operator to precisely monitor the interaction between laser and tissue in real time. In addition, the system designed by Kwok and Chan adopted machine learning to improve accuracy. The system performed with a tracking error of less than 0.2 millimetres during validation tests.
Next Kwok and Chan plan to make the device smaller. “Through miniaturisation it will be possible for the robot to access more confined sites such as the nasal cavity and sinus cavity. We will also implement some specific image sequences so that images can be fed back more quickly back to the robot” said Kwok.
“The system enabled direct exposure of the ablation laser to the target lesion, without the need for positioning patients with extreme neck extension to accommodate rigid laser micromanipulators. Together with MRI guidance, clinicians could give intuitive and precise feedback of the ablation process, which is critical for function preservation of surrounding structures” said Chan, commenting on the performance of the system in testing.
The team’s research was published in Science Robotics.
To view Kwok’s Croucher profile, please click here.