Magnetic Resonance Imaging‐Compatible Optically Powered Miniature Wireless Modular Lorentz Force Actuators

• Published in: Advanced science Vol. 8; no. 2; pp. 2002948 - n/a
• Main Authors: Mutlu, Senol, Yasa, Oncay, Erin, Onder, Sitti, Metin
• Format: Journal Article
• Language: English
• Published: Germany John Wiley & Sons, Inc 01.01.2021; John Wiley and Sons Inc; Wiley
• Subjects: Electric currents; Lorentz force actuator; Magnetic fields; Magnetic resonance imaging; MRI‐compatible; optical actuation; Photovoltaic cells; Robotics; Scanners; Wire; wireless actuation; MRI‐compatible; optical actuation; magnetic resonance imaging; wireless actuation; Lorentz force actuator
• ISSN: 2198-3844; 2198-3844
• DOI: 10.1002/advs.202002948

Minimally invasive medical procedures under magnetic resonance imaging (MRI) guidance have significant clinical promise. However, this potential has not been fully realized yet due to challenges regarding MRI compatibility and miniaturization of active and precise positioning systems inside MRI scanners, i.e., restrictions on ferromagnetic materials and long conductive cables and limited space around the patient for additional instrumentation. Lorentz force‐based electromagnetic actuators can overcome these challenges with the help of very high, axial, and uniform magnetic fields (3–7 Tesla) of the scanners. Here, a miniature, MRI‐compatible, and optically powered wireless Lorentz force actuator module consisting of a solar cell and a coil with a small volume of 2.5 × 2.5 × 3.0 mm3 is proposed. Many of such actuator modules can be used to create various wireless active structures for future interventional MRI applications, such as positioning needles, markers, or other medical tools on the skin of a patient. As proof‐of‐concept prototypes toward such applications, a single actuator module that bends a flexible beam, four modules that rotate around an axis, and six modules that roll as a sphere are demonstrated inside a 7 Tesla preclinical MRI scanner. Wireless, optically powered, miniature, modular, and magnetic resonance imaging (MRI) compatible Lorentz force actuators are proposed. Single actuator bending a flexible beam, four actuators forming a rotor, and six actuators forming a rolling sphere have been demonstrated inside a 7 Tesla MRI scanner. They can be used in future interventional MRI applications, e.g., positioning biopsy needles on patient's skin.