In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy

Xin Liu

will defend his dissertation

A Novel Transmission Mechanism for MRI Compatible Surgery Robot

Abstract

Minimally invasive surgery (MIS) techniques provide reduced patient discomfort, faster healing time, decreased risk of complications, and better overall patient outcomes. Medical imaging guidance is particularly crucial for MIS in which the procedure is performed through small openings in the body which resulting in limited sensory information available to surgeon compared with the open approach. Magnetic Resonance Imaging (MRI) is an intrinsically three-dimensional (3D) modality which offers high contrast and spatial resolution and a plethora of soft tissue contrast mechanisms for assessment of anatomical morphology and function. These benefits, in addition to the fact that it does not require ionizing radiation, make it a desirable methodology for image guided interventions (IGI). An impediment to those advancements, however, is the limited access to patient, especially with the high-field cylindrical magnetic resonance (MR) scanners. To address the limited accessibility and facilitate real-time guidance of IGI, remotely actuated and controlled MRI compatible manipulators have been introduced.

The MRI compatible interventional systems require appropriate forms of actuation. The commonly used electromagnetic actuators by many robotic system, like surgical robots, are, in general, not compatible with the MRI environment owing to their magnetically susceptible materials and electromagnetic components which are MR unsafe. In this work, we propose a novel transmission mechanism, herein referred to as Solid-Media Transmission (SMT), to transmit force from MR unsafe components located outside of the MR environment to the end effectors which are MR safe or MR conditional. We focus on the design, fabrication and control of SMT based actuator and an integrated robotic system that is aimed to perform the task of surgical tool or needle placement. Experimental studies have demonstrated the feasibility and characteristics of the SMT and SMT enabled devices for MRI guided intervention.

Date: Wednesday, September 6, 2017
Time: 10:30 AM
Place: PGH 550
Advisor: Dr. Nikolaos V. Tsekos

Faculty, students, and the general public are invited.