Actuation Mechanisms Used in MRI-Compatible Robotic Surgeries: A Review

Abstract

There has been increasing use of robotic surgery over the years, as it has evolved as an improvement over minimally invasive surgery (MIS), where a surgeon can use a tele-manipulator to operate on a patient. Magnetic resonance imaging (MRI) has become the leading form of image acquisition due to its ability to produce high resolution images during robotically assisted MIS. However, the MRI scanner places conditions on the robots that allow only certain compatible actuation methods used in the robotic system to negate large interference that hinders the image quality. The current review focused on the four main MRI-compatible actuation mechanisms: hydraulic, pneumatic, piezoelectric, and shape memory alloy. This review mainly discussed signal-to-noise ratio (SNR) reduction, performance, and limitations from the recent publications on MRI-compatible robotic surgeries. Favorable MRI compatibility with low SNR reduction, performance, and simple implementation was observed to be the most important characteristics of a proper actuation mechanism for MRI robotic surgeries. After reviewing each approach, it was concluded that shape memory alloy, despite having a form of limitation, demonstrated to be more favorable compared to other actuation methods because of factors such as low cost, negligible SNR reduction, and high-power output for medical interventions