Electromechanical design and construction of a rotating radio-frequency coil system for applications in magnetic resonance.
While recent studies have shown that rotating a single radio-frequency (RF) coil during the acquisition of magnetic resonance (MR) images provides a number of hardware advantages (i.e., requires only one RF channel, avoids coil-coil coupling and facilitates large-scale multinuclear imaging), they did not describe in detail how to build a rotating RF coil system. This paper presents detailed engineering information on the electromechanical design and construction of a MR-compatible RRFC system for human head imaging at 2 T. A custom-made (bladeless) pneumatic Tesla turbine was used to rotate the RF coil at a constant velocity, while an infrared optical encoder measured the selected frequency of rotation. Once the rotating structure was mechanically balanced and the compressed air supply suitably regulated, the maximum frequency of rotation measured ~14.5 Hz with a 2.4% frequency variation over time. MR images of a water phantom and human head were obtained using the rotating RF head coil system.
School of Information Technology and Electrical Engineering, The University of Queensland, Queensland, Australia. trakic@itee.uq.edu.au
Adnan
A
Trakic
Ewald
E
Weber
Bing Keong
BK
Li
Hua
H
Wang
Feng
F
Liu
Craig
C
Engstrom
Stuart
S
Crozier
D001921:Brain / Q000033:anatomy & histology; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006801:Humans; D007089:Image Enhancement / Q000295:instrumentation*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008280:Magnetics / Q000295:instrumentation*; D055617:Micro-Electrical-Mechanical Systems / Q000295:instrumentation*; D011846:Radio Waves; D012399:Rotation; D014159:Transducers