TRADITIONAL POSTER - ismrm

Poster Sessions
1499. A 4-Element Receive Array with Integrated Preamplifiers for Mouse Brain Imaging in a 14T Vertical
Bore Scanner
Stephen Dodd 1 , Herman Douglas Morris 2 , Joseph Murphy-Boesch 1 , Hellmut Merkle 1 , Alan Koretsky 1
1 Laboratory of Functional and Molecular Imaging, NINDS, National Institutes of Health, Bethesda, MD, United States; 2 Mouse
Imaging Facility, National Institutes of Health, Bethesda, MD, United States
In order to take advantage of the sensitivity that high fields offer we have developed and describe here a 4-element receive-only array design for parallel
imaging of the mouse brain at 14 T. To achieve the necessary decoupling between array elements we designed and built small, low noise and low input
impedance preamplifiers which can fit in the limited diameter of the vertical bore magnet.
Double Tuned RF Coils
Hall B Wednesday 13:30-15:30
1500. A Nested Dual Frequency Birdcage/Stripline Coil for Sodium/Proton Brain Imaging at 7T
Graham C. Wiggins 1 , Ryan Brown 1 , Lazar Fleysher 1 , Bei Zhang 1 , Bernd Stoeckel 2 , Matilde Inglese 1,3 ,
Daniel K. Sodickson 1
1 Radiology, Center for Biomedical Imaging, NYU School of Medicine, New York, NY, United States; 2 Siemens Medical Solutions
USA Inc., New York, NY, United States; 3 Neurology , NYU Medical Center, New York, NY, United States
The design of a novel dual frequency coil for 7T sodium/proton brain imaging is discussed. The nested coil utilized a high-pass birdcage for sodium
detection and an eight-channel stripline array for proton detection. This design showed minimal interaction between the sodium and proton coils, allowing
independent tuning at both frequencies. The proton striplines partially shielded the sodium birdcage, resulting in only an 8% SNR loss compared to that of
the isolated birdcage, while transmit efficiency was reduced by 20%. The proton stripline coil provided adequate sensitivity for anatomical imaging and B0
shimming.
1501. Double Tuned 31P/1H Elliptical Transceiver Phased Array for the Human Brain Studies at 7 T
Nikolai I. Avdievich 1 , Jullie W. Pan 1 , Hoby P. Hetherington 1
1 Neurosurgery, Yale University, New Haven, CT, United States
The improved SNR at 7T provides significant advantages for both 1H and X nuclei (31P, 13C etc). At 7T, transceiver phased arrays improve B1
homogeneity, transmit efficiency, and peripheral SNR compare to volume coils. Therefore, double tuned transceiver arrays may provide substantial
advantages over conventional double tuned volume head coils. However, they are substantially more complicated than single tuned arrays since all coils
must be decoupled at both frequencies. We have developed a 16-element (8 elements per frequency) 31P/1H 7T transceiver phased head array. The double
tuned transceiver array improved both B1 homogeneity and efficiency in comparison to the TEM.
1502. Single-Input Double-Tuned Birdcage Coil with Identical B1 Field Profile for 1H and 19F Imaging
Lingzhi Hu 1 , Frank D. Hockett 1 , Junjie Chen 1 , Gregory M. Lanza 1 , Samuel A. Wickline 1
1 Washington University School of Medicine, St. Louis, MO, United States
Based on coupled-resonator model, we have designed a single-input double-tuned birdcage working at both 1H and 19F frequencies on 4.7T MRI scanner.
The good matching property and homogeneity of B1 field have been testified by S11 and S21 measurement and in vivo demonstration. To achieve the
highest sensitivity, we have also integrated an active decoupled surface coil with the double-tuned birdcage and increased the local SNR by over 10 folds. As
the standard birdcage structure is preserved, the sensitivity profile of this new double-tuned birdcage is inherently identical at 1H and 19F resonant
frequencies.
1503. High SNR Dual Tuned Sodium/Proton Knee Coil
Ronald D. Watkins 1 , Ernesto Staroswiecki 1,2 , Neal Bangerter 3 , Brian Hargreaves 1 , Garry Gold 1
1 Radiology, Stanford University, Stanford, CA, United States; 2 Electrical Engineering, Stanford University, Stanford, CA, United
States; 3 Electrical and Computer Engineering, Brigham Young University, Provo, UT, United States
Preliminary results from a dual tuned 23Na sodium 1H proton knee coil are presented. A multiple ring birdcage design has been employed providing high
sensitivity and uniformity to both nuclei without the need for frequency traps. Both coil sections are circularly polarized quadrature coils with direct drive
cable connections. Cables are routed to a common potential node avoiding the need for baluns and avoiding parasitic cable loops. Registered images are
presented for both sodium and proton acquisitions, avoiding the need to change the RF coil during the study
1504. Design and Construction of a Heteronuclear 1H and 31P Double Tuned Coil for Breast Imaging and
Spectroscopy
Sergei Obruchkov 1 , Kenneth Bradshaw 2 , Michael D. Noseworthy 3
1 Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, ON, Canada; 2 Sentinelle Medical, Toronto, ON,
Canada; 3 Electrical and Computer Engineering, McMaster University, Hamilton, ON, Canada
Dual tuned surface coil (31P and 1H) was designed and build to have high performance parameters for both channels. The coil was build to integrate into a
Sentinelle Vanguard table for 3T Signa GE system. The ability to transmit on both channels simultaneously makes it possible to perform decoupling using
the same coil. 1H imaging and 31P spectroscopy was demonstrated on the above coil.