@article{oai:nagoya.repo.nii.ac.jp:00017479, author = {Matsushima, Shigeru and Sasaki, Fumio and Uchiyama, Yukio and Fuwa, Nobukazu and Andoh, Manabu and Maeda, Hisatochi and Kinosada, Yasutomi}, issue = {1}, journal = {放射線医学物理 = Japanese journal of medical physics}, month = {Mar}, note = {Magnetization transfer ratios (MTRs) of tissues with different characteristics were investigated. Cross-relaxation 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 MnCl2 solution with various concentrations of gelatin and MnCl2. 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 MnCl2 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.}, pages = {1--8}, title = {Tissue characterization by magnetization transfer ratio : Evaluate of the MTRs in breast tunors, globus pallidus and nasopharyngeal tumors}, volume = {17}, year = {1997} }