Hadas Ziso: novel robots for neurosurgery

Hadas Ziso

Hadas Ziso is a doctoral student in the Faculty of Mechanical engineering at the Technion and winner of the Levi Eshkol Prize for 2013. “I began my academic path in the Faculty of Biomedical Engineering,” says Ziso, “where I earned my B.Sc. and M.Sc. My research, advised by Prof. Eitan Kimel, examined the treatment of cancerous tumors using ultrasound and microbubbles. I then worked for several years in the medical sector, until my return to the university as a doctoral student, advised by Prof. Moshe Shoham (head of the medical robotics lab) and Prof. Menashe Zaaroor (head of the Department of Neurosurgery at Rambam Medical Center).”

“My research involves the development of a novel robot for minimally invasive neurosurgery. This robotic system is unique for several reasons: first, the treatment will be executed automatically, under the supervision of the surgeon, according to a treatment plan based on CT/MRI scans and combined with real-time detection of the cancerous tissue. Second, the robotic system will conduct the surgery via a ~4 mm keyhole in the skull and will be able to treat tumors up to 6 cm in diameter.

The robot is equipped with a mechanism of a rigid external needle and a semi-flexible inner needle that gives the system three-dimensional freedom of movement. The external needle moves vertically and rotates, while the inner needle moves laterally. One of the main technological challenges of this project, apart from the miniaturization of the detection and therapeutic tools, is the development of a needle mechanism that can turn a sharp corner. The inner needle will have to endure a 90-degree curvature in the opening of the external needle, and still be strong enough to bear lateral loads. It must be straight upon exit, in order to accurately move the attached detection and therapeutic tools to the planned destination. A few mechanisms that met these requirements were investigated, including thin-wall tube buckling, magnetic bead chain, Nitinol wire and a tensegrity mast.

The two diagnostic and therapeutic methods that meet the system specifications, both clinically and mechanically, and are currently under evaluation are: tumor detection using 5-ALA fluorescence spectroscopy or electrical impedance measurements; and the tumor will be treated with Laser ablation or high-frequency RF ablation, in which radio wave energy vaporizes the tissue. The various detection techniques will be evaluated in clinical trials in-vitro and the therapies will be evaluated in pre-clinical trials.”