Safe, Nonmagnetic Fluidic Actuator for MRI-Guided Interventions

Achievement date: 
2014
Outcome/accomplishment: 

Researchers affiliated with the Center for Compact and Efficient Fluid Power (CCEFP), an NSF-funded Engineering Research Center (ERC) headquartered at the University of Minnesota, have taken a significant step toward using fluid-power solutions for health care. Specifically, the researchers recently invented a fluid-powered actuator for interventions guided by magnetic resonance imaging (MRI).

Impact/benefits: 

Fluid power is an ideal form of robotic actuation inside the scanner’s magnetic field because actuators can be designed free of magnetic and electrical components. However, there are no fluid-power actuators readily available that offer the safety, sterilizability, and precision performance required for medical robotic systems. The CCEFP researchers’ work represents a major movement to overcome this transformational barrier.

 

Explanation/Background: 

MRI offers many benefits to image-guided interventions. These benefits include excellent soft tissue distinction, little to no repositioning of the patient, and zero radiation exposure. However, the closed, narrow bore of a high-field MRI scanner limits clinician access to the patient, so an MRI-compatible robot is essentially required for many potential interventions. With a compact design made possible by additive manufacturing, a first prototype was made (see figure). Employing inchworm-like behavior, the device is intrinsically safe. The linear actuator can advance or retract a needle in small, discrete steps. The device’s pneumatic bellows and pinching mechanism are hermetically sealed for clean performance in sterile environments.