IN-VIVO H-1 MRS CHOLINE - CORRELATION WITH IN-VITRO CHEMISTRY HISTOLOGY

We correlated the in vivo H-1 Magnetic Resonance Spectroscopy (MRS) co ncentration of the choline peak (CHO) with in vitrochemical measures o f choline-containing compounds and a histological grade of cellularity in 18 patients with neoplastic and infectious brain lesions. Gas-chro matography-mass-spectrometry (GCMS) was used to measure the concentrat ions of free choline (Cho), glycerophosphocholine (GPCho), phosphochol ine (PCho) and phosphatidylcholine (PtdCho) from biopsies in the same area where MRS was performed. Cellular density, free Cho, PCho and GPC ho were the strongest determinants of H-1 MRS CHO while PtdCho was not . Just as the H-1 MRS 2.0 peak reflects both the concentration of n-ac etyl-1-aspartate and neuronal density, the H-1 MRS 3.2 peak reflects t he concentration of water-soluble choline-containing compounds and cel lular density.