Enhancing Minimally-Invasive Neurosurgery through the Development of Magnetic-Resonance Compatible Bipolar Cautery and Scissor Tool Tips

Claudia Lutfallah (1,2), Thomas Looi (2), James Drake (1,2)

(1) Institute of Biomaterials and Biomedical Engineering

(2)The Hospital for Sick Children (SickKids)

Many surgical instruments are fabricated from stainless steel, a ferrous metal that when introduced to a magnetic resonance (MR) field, can become a dangerous projectile that accelerates toward the magnet. Stereotaxy is a minimally-invasive neurosurgical technique that uses preoperative magnetic resonance imaging (MRI) to provide neurosurgeons with high resolution images of the brain before performing surgery through a small burr hole in the skull. However, current intraoperative tools lack the ability to update the image of the brain in real-time throughout the procedure because they are limited by MR-compatibility of the surgical instruments. Systems are being developed that allow real-time MRI of the brain during minimally invasive robot-assisted surgery. As systems like these are being developed to increase the accuracy of tool position and location in the brain, the need for MR-compatible surgical instruments is rising. Bipolar cautery and scissor tips are common surgical instruments used to control bleeding when cutting and cauterizing tissue during brain tumour resection. The tool operates using an electrosurgical unit that varies its output waveform to permit cutting and cauterization of tissue depending on the surgeon’s desired application. Traditional bipolar tools have large, flat tips that act as an extension of the surgeon’s hands. These are not practical for minimally-invasive surgery because it would be difficult to navigate the instrument through a small burr hole. The goal of this project is to develop a pair of MR-compatible bipolar cautery and scissor tips that can be used for robotic and manual interventions in minimally-invasive neurosurgery to safely control hemostasis during brain tumour resection.