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Tsuyoshi Matsuda

Publications and source records attributed to Tsuyoshi Matsuda.

22 records · Page 2Linked to original sources
PubMed2002

Differentiation of prostate cancer from benign prostate hypertrophy using dual-echo dynamic contrast MR imaging.

OBJECTIVE: To investigate the usefulness of dynamic contrast magnetic resonance (MR) imaging in the differentiation of prostate cancer (PC) from benign prostate hypertrophy (BPH). MATERIALS AND METHODS: Eleven PC patients and 13 BPH patients were entered into the analysis. The mean gradient (MG) was calculated from the T2* term-eliminated time-signal intensity curve obtained from dynamic contrast MR data, and the MG of PC and that of BPH were compared. RESULTS: The MG of PC was significantly higher than that of BPH. When the threshold value was set to 1.88% per s for discriminating PC from BPH, the sensitivity, specificity, and accuracy were 100, 85, and 92%, respectively. CONCLUSION: The MG, which is derived from the T2* term-eliminated time-signal intensity curve, may be a useful index for differentiating PC from BPH.

Adult↗
PubMed2002

Measurement of the vascularity and vascular leakage of gliomas by double-echo dynamic magnetic resonance imaging: a preliminary study.

RATIONALE AND OBJECTIVE: To evaluate the vascularity and vascular leakage of well-enhanced gliomas by double-echo dynamic magnetic resonance (MR) imaging. MATERIALS AND METHODS: Eight patients with glioblastoma multiforme (GBM) and two patients with juvenile pilocytic astrocytoma (JPA) were studied. Double-echo dynamic MR imaging was utilized to separate the T2* shortening effect and the T1 shortening effect. The former was represented by the vascularity index, and the latter was represented by the leakage index. These indexes were compared with histopathologic data. RESULTS: The mean vascularity index of the GBM was higher than that of the JPA (mean +/- SD, 3.48 +/- 1.57 [GBM] versus 0.51 +/- 0.29 [JPA]), and the mean leakage index of the JPA was higher than that of the GBM (1.35 +/- 0.87 [JPA] versus 0.27 +/- 0.15 [GBM]). Abundant vascularity was noted in the tight interstitial space in the pathologic specimen of GBM. Conversely, sparse vasculature was observed in the wide interstitial space in the pathologic specimen of JPA. CONCLUSION: This method may enable better characterization of grade in well-enhanced glioma by providing the information on the vascularity and leakage indexes.

Adult↗
PubMedDate not supplied

H(2) (15)0 positron emission tomography validation of semiquantitative prostate blood flow determined by double-echo dynamic MRI: a preliminary study.

PURPOSE: Information regarding prostate blood flow as determined by positron emission tomography (PET) with H 0 may provide useful information about tumor diagnosis; however, PET requires a cyclotron for the production of an extremely short half-life (2 minutes) tracer. Therefore, the aim of this study was to propose a complementary index for blood flow as determined by MRI to validate the results and compare them with PET, especially for prostate tissue. METHODS: Six consecutive patients with prostate disease were studied. The two semiquantitative indices for tumor blood flow were calculated from the time-concentration curve measured from double-echo MR images. The theory of nondiffusible tracers by means of indicator dilution theory was applied to MR data. The relative regional blood flow (rrBF) was calculated as the ratio of the relative regional blood volume to relative regional mean transit time. Another proposed index was the maximum height of the time-concentration curve. PET studies were also performed, and absolute blood flow values were calculated for each subject. These indices calculated from different modalities were then compared. RESULTS: A significant correlation was found between the rrBF and the absolute blood flow as determined by PET (r = 0.69, p < 0.005). A significant correlation was also found between the maximum height of the time-concentration curve and the absolute blood flow (r = 0.85, p < 0.0001). CONCLUSIONS: The semiquantitative tumor blood flow indices measured with MRI have a good correlation with the corresponding measurements by PET; therefore, these indices may provide useful information about tumor diagnosis in clinical settings.

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