Localized proton MR spectroscopy of citrate in vitro and of the human prostate in vivo at 1.5 T.

Citrate is a secretory product of the normal prostate, a lack of citrate in prostate tissue is expected to be pathognomonic for adenocarcinoma. In the present study proton AB-signal characteristics of citrate at low field strength of 1.5 T were investigated by volume selective spectroscopic and theoretical methods. The nonappearance of fast phase modulation of the J-coupled system at low field strength in vivo is verified by measurements of sodium citrate solution. In vivo localized spectroscopy of small volume elements of (2 cm)3 with the double spin-echo method within the prostatic gland provides citrate signal reception even using a Helmholtz coil with 170-mm diameter. Volume selective proton spectra with different echo times are presented which are comparable to spectra acquired by former authors with endorectal coils.