External standard method for the in vivo quantification of choline‐containing compounds in breast tumors by proton MR spectroscopy at 1.5 Tesla

Quantification of choline-containing compounds observed with (1)H MRS of breast tumors is of interest since such compounds have been linked to malignancy. Experiments were performed at 1.5 T with an external standard containing phosphocholine for calibration. In phantom studies, good precision was achieved after correction for T(1)/T(2) effects. T(2) values for choline were estimated for two breast cancer patients. A choline concentration of 2.0 mM was calculated for a third patient, a result comparable to in vitro findings. Magn Reson Med 46:189-192, 2001.