A design for a double-tuned birdcage coil for use in an integrated MRI/MRS examination

• Published in: Journal of magnetic resonance (1969) 1990-08, Vol.89 (1), p.41-50
• Main Authors: Isaac, Gamaliel, Schnall, Mitchell D, Lenkinski, Robert E, Vogele, Katherine
• Format: Article
• Language: English
• Subjects: Analytical chemistry; Chemistry; Exact sciences and technology; Spectrometric and optical methods
• ISSN: 0022-2364; 1557-8968
• DOI: 10.1016/0022-2364(90)90160-B

The performance of a new design for a double-tuned birdcage volume coil using multiple-pole tuning elements was evaluated. The relative signal to noise of a double-tuned four-strut extremity coil (22 cm long, 15 cm diameter) was compared with that of two single-tuned extremity coils of the same dimensions. The signal to noise of the double-tuned extremity coil at the 1H frequency was 92 ± 3% of that obtained with the single-tuned proton coil. The signal-to-noise ratio obtained with the double-tuned coil at the 31P frequency was 94 ± 4% of the signal to noise obtained with the single-tuned 31P Coil. The signal-to-noise comparisons between the extremity coils show that the double-tuned design is competitive with single-tuned coils of similar design at both frequencies and may actually make possible images and spectra with superior signal to noise to that obtainable with single-tuned coils in an integrated exam. These preliminary experiments show that this new design has advantages over single-tuned coils for generating spatially localized 31P spectra. This dual capability offers clear advantages for the integration of MRI and MRS in the clinical setting.