Robotic system to be used in brain surgery

15 June 2018

An engineering team led by Dr Kwok Ka-wai of the University of Hong Kong has developed a robot to improve the accuracy of brain surgery when used inside a magnetic resonance imaging scanner.

The invention can improve the precision of stereotactic neurosurgery. Traditionally, surgeons use magnetic resonance imaging scanners to locate targets before opening the patient’s skull. But as the skull is opened, brain tissue may shift, so do the targets. Without a real-time update, more time is required to ensure surrounding brain tissue is not damaged during the operation. There is also no currently available technology to record responses to stimulation at certain sites within the brain during the surgery so patients are also required to stay awake under local anaesthesia and interact verbally and physically with the surgeon.

To improve the process, Dr Kwok Ka-wai (Croucher Fellowship 2013) and his colleagues including Mr Lee Kit-hang (Croucher Studentship 2015) of the University of Hong Kong developed a robotic system with three-dimensional tracking markers to monitor the location of targets during surgery.

Traditionally, robots are built using metal components such as electromagnetic motors which cannot be used in MRI environments. The technology developed my Kwok is hydraulic and can be used in a scanner without affecting image quality.

Hydraulic driving robot in a MRI scanner

The robot fits inside a standard magnetic resonance imaging head coil and requires a very small invasive anchorage area. Patients are not required to stay awake and the operation time can be shortened to six hours from the normal eight hours.

“There is still 1.7-millimeter sighting error and we hope to further reduce it to one millimetre,” said Kwok.

The research team will conduct further clinical studies to determine the efficacy of the system. It is believed that the system can also be applied to other interventions requiring MRI guidance, for example, cardiac catheterization, prostate or breast biopsy.

Invited to comment on the development, Dr Chan Tat-ming of the Chinese University of Hong Kong said, "Similar manual operation system has been developed by overseas engineers but electric mortars are used and will interfere MRI scanners. The patient needs to be moved in and out of the scanner throughout the operation.” 

“This new system can spare the unnecessary effort,” added Chan. 

The team received the best conference paper award in the largest international forum for robotics scientists, the IEEE International Conference on Robotics and Automation 2018 in May. winning in all categories including robot vision, cognitive robotics, robot manipulation and unmanned aerial vehicles. 



Dr Ka-Wai Kwok received the B.Eng and M.Phil degrees from Automation and Computer-Aided Engineering, The Chinese University of Hong Kong. In 2011, he completed the PhD training in The Hamlyn Centre for Robotic Surgery, Imperial College London, where he continued research on surgical robotics as a postdoctoral fellow. Dr. Kwok is the recipient of the Croucher Foundation Fellowship 2013, which supported his postdoctoral research jointly hosted by The University of Georgia, and Brigham and Women's Hospital - Harvard Medical School. 

To view Dr Kwok's Croucher profile, please click here

Mr Lee Kit Hang obtained his bachelor’s degree (1st Class Honours) in Mechanical and Automation Engineering, The Chinese University of Hong Kong (CUHK) in 2011, where he already found strong interest in robotics. During his undergraduate study, he also participated in one-year exchange program hosted by Technical University of Denmark (DTU). Lee currently pursue PhD under the co-supervision of Prof. Kam-Yim Sze and Dr. Ka-Wai Kwok. He is also the recipient of Croucher Foundation Research Scholarship 2015 supporting his research studies in the field of image-guided robotic interventional systems. 

To view Mr Lee's Croucher profile, please click here