Superconducting single and phased-array probes for clinical and research MRI

• Published in: IEEE transactions on applied superconductivity Vol. 13; no. 2; pp. 1050 - 1055
• Main Authors: Wosik, J., Lei-Ming Xie, Nesteruk, K., Lian Xue, Bankson, J.A., Hazle, J.D.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: New York, NY IEEE 01-06-2003; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Applied sciences; Design; Design. Technologies. Operation analysis. Testing; Electrical engineering. Electrical power engineering; Electromagnets; Electronics; Exact sciences and technology; Integrated circuits; Magnetic noise; Magnetic resonance imaging; Microelectronic fabrication (materials and surfaces technology); Noise; Phased arrays; Probes; R&D; Research & development; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Signal to noise ratio; Superconducting coils; Superconducting device noise; Superconducting devices; Superconductivity; Temperature; Various equipment and components; Yttrium barium copper oxide; Patterning; magnetic resonance imaging; rf resonators; Cooling; Thermal management (packaging); Noise reduction; Phased array; High temperature superconductors; Phased array antenna; Experimental study; Nuclear magnetic resonance imaging; Superconducting coils; Microelectronic fabrication; partial parallel imaging; Cooling system; Parallel processing; Thermal noise; Radio receivers; Comparative study; Gain; High temperature superconductor; Room temperature; Signal to noise ratio
• ISSN: 1051-8223; 1558-2515
• DOI: 10.1109/TASC.2003.814148

Significant improvement of the signal-to-noise ratio (SNR) for magnetic resonance imaging (MRI) applications, in which the thermal noise of the rf receiver probe dominates the system noise can be achieved by cooling down a normal metal probe or by using superconductors. In this work, the SNR enhancement expected from using superconductors for single coil and/or phased array designs are calculated, discussed and compared with some experimental results. We also report on the design and fabrication of a 63.8 MHz probe (1.5 Tesla) consisting of patterned, copper or YBCO films deposited on both sides on a 5 cm LaAlO/sub 3/ substrate. The unloaded Q of the normal metal probe at room temperature and at 77 K was about 400 and 1000, respectively, while the YBCO probe exhibited a Q of 40 000 at 77 K. Five-cm diameter probes cooled to 77 K were superior to their identically designed room temperature equivalents, and provided SNR gains at 1.5 Tesla of 3 and 2 times for YBCO and cooled normal metal, respectively. The application of superconducting coils in conjunction with recently developed techniques for significant reduction of MRI acquisition times by using parallel processing with phased array probes is discussed.