An inductively coupled, doubly tuned resonator for in vivo nuclear magnetic resonance spectroscopy

We present a coil designed for in vivo P-31 and H-1 nuclear magnetic resona nce spectroscopy which consists of a doubly tuned resonator inductively cou pled to separate H-1 and P-31 feed coils. The advantages of the resonator i nclude the ability to H-1 shim over the same volume from which P-31 spectra are extracted by using a single sample coil, elimination of coupling probl ems between separate H-1 and P-31 coils, ease of design and tuning over con ventional double-tuned coils, and reduced match/tune sensitivity to coil lo ading, which is important in in vivo applications. We have used this coil t o collect phosphorus spectra from the in situ heart of the western painted turtle (Chrysemys picta bellii) at 2 T. The total heart volume was less tha n 1 mL and acquisition time was just under 10 min. (C) 1999 American Instit ute of Physics. [S0034-6748(99)01708-6].