1997 年 17 巻 1 号 p. 1-8
Magnetization transfer ratios (MTRs) of tissues with different characteristics were investigated. Crossrelaxation rates of solutions with different protein concentrations were studied. We evaluated the MTRs of female breast tumors, the globus pallidus, and nasopharyngeal tumors, and assessed the usefulness of MTRs in determining tissue characteristics.
In phantom studies, we measured MTRs using gelatin and MnC12 solution with various concentrations of gelatin and MnC12. MTRs were measured using pairs of images obtained by conventional SPGR sequence and MT - prepared SPGR sequence. MTRs, defined as the percentage of signal loss between unsaturated and saturated images, were calculated using the equation (Mo - Ms) /Mo, where Mo is the measured signal intensity on the conventional SPGR images, and Ms is the measured signal intensity on the MT - prepared SPGR images. We investigated relationships between pathological findings and MTRs of breast tumors, between liver function and MTRs of globus pallidus, and between the DNA index and MTRs of nasopharyngeal tumors.
MTRs increased with increased gelatin concentration, but decreased as the MnC1 2 concentration increased. MTRs of breast carcinoma were higher than those of benign tumors. MTRs of globus pallidus showed a correlation with liver function (ChE: r = 0.79, PT: r = 0.75, ICGR15: r 0.98). MTRs of aneuploid nasopharyngeal tumors had high MTRs. MTR is a good indicator of protein concentration and could be a new and useful parameter for tissue characterization.
