Polarization transfer methods can substantially enhance NMR signals from nu
clei of low gamma, which are J-coupled to nuclei of high gamma, but to date
have had limited application for in vivo P-31 MRS studies. They require bo
th accurate flip angles and good localization in order to achieve their pot
ential. Described here is an implementation of the insensitive nuclei enhan
ced by polarization transfer (INEPT) polarization transfer method using seg
mented adiabatic BIR4 RF pulses. Localization uses ISIS, applied to the cou
pled H-1 spins. Detailed analysis is performed to evaluate the specific abs
orption rate power deposition when using surface coils. Polarization transf
er, localization capability, and use with surface coils are demonstrated us
ing suitable test objects. Finally, in vivo data are presented from the liv
er of a normal volunteer in which the signals from the phosphodiester peaks
are substantially enhanced. (C) 2000 Wiley-Liss, Inc.