A high-throughput eight-channel probe head for murine MRI at 9.4 T.
Murine MRI studies are conducted on dedicated MR systems, typically equipped with ultra-high-field magnets (>or=4.7 T; bore size: approximately 12-25 cm), using a single transmit-receive coil (volume or surface coil in linear or quadrature mode) or a transmit-receive coil combination. Here, we report on the design and characterization of an eight-channel volume receive-coil array for murine MRI at 400 MHz. The array was combined with a volume-transmit coil and integrated into one probe head. Therefore, the animal handling is fully decoupled from the radiofrequency setup. Furthermore, fixed tune and match of the coils and a reduced number of connectors minimized the setup time. Optimized preamplifier design was essential for minimizing the noise coupling between the elements. A comprehensive characterization of transmit volume resonator and receive coil array is provided. The performance of the coil array is compared to a quadrature-driven birdcage coil with identical sensitive volume. It is shown that the miniature size of the elements resulted in coil noise domination and therefore reduced signal-to-noise-ratio performance in the center compared to the quadrature birdcage. However, it allowed for 3-fold accelerated imaging of mice in vivo, reducing scan time requirements and thus increasing the number of mice that can be scanned per unit of time.
Lanz
Titus
T
Rapid Biomedical GmbH, Rimpar, Germany. titus.lanz@rapidbiomed.de
Müller
Matthias
M
Barnes
Hannah
H
Neubauer
Stefan
S
Schneider
Jürgen E
JE
D000818:Animals; D007091:Image Processing, Computer-Assisted / Q000295:instrumentation / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000145:classification / Q000295:instrumentation* / Q000379:methods; D051379:Mice; D019047:Phantoms, Imaging