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Im Sang-Jin Shim Jae-Hyuk Kim Joo-Yeon Baek Hyeon-Man 《Applied magnetic resonance》2020,51(3):255-276
Applied Magnetic Resonance - Total cerebral volume increases very rapidly in childhood, peaking in early teenage years then declining in adolescence. However, most studies quantified only one or... 相似文献
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Proton magnetic resonance spectroscopy (1H MRS) and dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) provide functional information, including vascular volume, vascular permeability and choline (Cho) metabolism. In this study, we applied these two imaging modalities to quantitatively characterize 36 malignant breast lesions in 32 patients and analyzed the correlation between them. Cho concentration was quantified by single-voxel 1H MRS using water as an internal reference. The measured Cho levels ranged from 0.32 to 10.47 mmol/kg, consistent with previously reported values. In 25 mass-type lesions, the Cho concentration was significantly correlated with tumor size (r=.69, P<.0002). In addition, the Cho level was found to be significantly higher in lesions presenting as mass-type lesions compared to non-mass-type diffuse enhancements (P=.035). The enhancement kinetics from tissues covered within each MRS voxel were measured and analyzed with a two-compartmental model to obtain pharmacokinetic parameters Ktrans and kep. A significant correlation was found between the Cho level and the pharmacokinetic parameter kep (r=.62, P<.0001), indicating that tissues with a high Cho level have higher wash-out rates in DCE MRI. The results suggest a correlation between Cho metabolism and angiogenesis activity, which might be explained by the association of Cho with cell replication and angiogenesis required to support tumor growth. 相似文献
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Sang-Young Kim Hyeon-Man Baek Jung-Hoon Lee Dae-Hyun Kim Jin-Young Jung Do-Wan Lee Jung-Whan Min Ji-Yeon Park Seu-Ran Lee Bo-Young Choe 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(1):533-541
In this work, we present the feasibility of using a parallel RF transmit with multiple RF sources imaging method (MultiTransmit imaging) in polymer gel dosimetry. Image quality and B1 field homogeneity was statistically better in the MultiTransmit imaging method than in conventional single source RF transmission imaging method. In particular, the standard uncertainty of R 2 was lower on the MultiTransmit images than on the conventional images. Furthermore, the MultiTransmit measurement showed improved dose resolution. Improved image quality and B1 homogeneity results in reduced dose uncertainty, thereby suggesting the feasibility of MultiTransmit MR imaging in gel dosimetry. 相似文献
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