Device For Remotely Tuning and Matching MRI/NMR Coils

Device For Remotely Tuning and
Matching MRI/NMR Coils
The University of Florida is seeking companies interested in commercializing a device for
remotely tuning the frequency and matching the impedance of a radio frequency coil used
in nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI). The problems
associated with tuning and matching NMR/MRI radio frequency (RF) coils have been addressed
in many different ways. The current methods include placing a lumped circuit of tuning and
matching capacitors in close proximity to the RF coil. However these current approaches suffer
from stray capacitances and tuning/matching inefficiencies that lead to instability. Also, current
designs require manual manipulation to adjust frequency and impedance which is not always
possible due to limited space. Our researchers have developed a technique and apparatus, using
a matching and tuning circuit, which eliminates stray capacitances and allows remote frequency/impedance
adjustments thus eliminating major tuning difficulties.
Applications
Device for optimizing performance adjustments made remotely to medical imaging systems,
high field research magnets, and commercial MRI/NMR systems
Advantages
t Eliminates stray capacitances, decreasing the pos-
sibility of misleading results and providing a market
advantage as most reliable MRI/NMR design
t Enables remote adjustment frequency and imped-
ance, simplifying operation and reducing costs that
are associated with training
t Decreases required setup time, reducing costs that
are associated with implementation
t Improves data quality, decreasing data acquisition
time and increasing number of patient studies that
can be conducted per day

Technology
This approach uses a combination of NMR coil reactance and cable impedance, all grounded to
create a purely resistive match and eliminate stray capacitances. This circuit, called the matching
tuning (M-T) box circuit, greatly improves tuning/matching efficiency, and is especially effective
at high fields with varying sample loads, and where space considerations are paramount. It also
allows for enhanced frequency and impedance adjustments to be made remotely when space for
accessing the mechanical matching components is limited or not available.
The Inventors
Melvin Daniel Clark, Ph.D., is a senior engineer at the McKnight Brain Institute at the
University of Florida. He designs, builds and tests radio frequency coils for the many NMR and
MRI high-field research magnets at the University of Florida and the National High Field Magnet
Laboratory at Florida State University. Prior to joining the University of Florida, Clark was
a research engineer with the Bioscience Division, Los Alamos National Laboratory, a research
engineer at the University of Alabama Center for Nuclear Magnetic Resonance, an avionic engineer
at the Hayes International Aircraft Corp in Birmingham, Ala., and a research and design
engineer at the Spacecraft Incorporated in Huntsville, Ala.
John R. Forder, Ph.D., is an associate professor of Radiology at the McKnight Brain Institute
at the University of Florida. He received his B.A. in Biology from the University of Vermont and
his Ph.D. in Pharmacology from the University of Michigan.
Contact:
Elizabeth Garami
University of Florida
Office of Technology Licensing
(352) 392-8929 • egarami@ufl.edu
UF #12303 Patent Pending