著者
Kazuki Oyama Fumihito Ichinohe Akira Yamada Yoshihiro Kitoh Yasuo Adachi Hayato Hayashihara Marcel D. Nickel Katsuya Maruyama Yasunari Fujinaga
出版者
Japanese Society for Magnetic Resonance in Medicine
雑誌
Magnetic Resonance in Medical Sciences (ISSN:13473182)
巻号頁・発行日
pp.mp.2022-0035, (Released:2022-08-23)
参考文献数
13
被引用文献数
2

Purpose: The optimal temporal resolution for free-breathing dynamic contrast-enhanced MRI (FBDCE-MRI) of the pancreas has not been determined. This study aimed to evaluate the appropriate temporal resolution to achieve good image quality and to perform pharmacokinetic analysis in FBDCE-MRI of the pancreas using golden-angle radial sparse parallel (GRASP).Methods: Sixteen participants (53 ± 15 years, eight females) undergoing FBDCE-MRI were included in this prospective study. Images were retrospectively reconstructed at four temporal resolutions (1.8, 3.0, 4.8, and 7.8s). Two radiologists (5 years of experience) evaluated the image quality of each reconstructed image by assessing the visualization of the celiac artery (CEA), the common hepatic artery, the splenic artery, each area of the pancreas, and artifacts using a 5-point scale. Using Tissue-4D, pharmacokinetic parameters were calculated for each area in the reconstructed images at each temporal resolution for 16 examinations, excluding two with errors in the pharmacokinetic modeling analysis. Friedman and Bonferroni tests were used for analysis. A P value < 0.05 was considered statistically significant.Results: During vascular assessment, only scores for the CEA at 7.8s were significantly lower than the other temporal resolutions. Scores of all pancreatic regions and artifacts were significantly lower at 1.8s than at 4.8s and 7.8s. In the pharmacokinetic analysis, all volume transfer coefficients (Ktrans), rate constants (Kep), and the initial area under the concentration curve (iAUC) in the pancreatic head and tail were significantly lower at 4.8s and 7.8s than at 1.8s. iAUC in the pancreatic body and extracellular extravascular volume fraction (Ve) in the pancreatic head were significantly lower at 7.8s than at 1.8s.Conclusion: A temporal resolution of 3.0s is appropriate to achieve image quality and perform pharmacokinetic analysis in FBDCE-MRI of the pancreas using GRASP.
著者
安達 康生 安高 真一郎 植松 康祐 アダチ ヤスオ アタカ シンイチロウ ウエマツ コウユウ Yasuo Adachi Ataka Shinichiro Koyu Uematsu
雑誌
国際研究論叢 : 大阪国際大学紀要 = OIU journal of international studies
巻号頁・発行日
vol.29, no.2, pp.47-62, 2016-01-31

The cellular automaton was created by John Von Neumann and Stanislaw Marcin Ulam. What Von Neumann was interested in was a machine which could replicate itself and the first such machine in the logical world was the Neumann cellular automaton. Since then, the cellular automaton has been expanded to many fields such as biology, history, and complex systems. This paper suggests closed social structure models with the method based on the cellular automaton. We succeeded in finding some interesting facts using simulations. The results gained can be applied to models such as closed social structures nowadays or the existence of living creatures.