Feasibility of quantitative imaging for glucose metabolism in liver using GlycoCEST Imaging.

• Project/Area Number: 17K17965
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Radiation science; Medical Physics and Radiological Technology
• Research Institution: Kagoshima University
• Principal Investigator: Iwanaga Takashi 鹿児島大学, 鹿児島大学病院, 主任診療放射線技師 (40444830)
• Project Period (FY): 2017-04-01 – 2022-03-31
• Project Status: Completed (Fiscal Year 2021)
• Budget Amount: ¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000); Fiscal Year 2019: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2018: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000); Fiscal Year 2017: ¥2,340,000 (Direct Cost: ¥1,800,000、Indirect Cost: ¥540,000)
• Keywords: CESTイメージング / Glycogen CEST / 肝臓 / MRI / Glycongen CEST / 肝臓糖代謝

Outline of Final Research Achievements

We optimized the scan parameters of GlycoCEST imaging through in vitro phantom experiments and optimal strength and duration of the saturation pulse for GlycoCEST were determined. The positive correlation was observed between GlycoCEST imaging and concentration of the bovin liver glycogen using a 3T clinical MRI. Our study revealed the CEST effect in GlycoCEST showed a tendency different from APT, since GlycoCEST was influenced by the direct water saturation effect when large RF saturation pulse strength was used.

Academic Significance and Societal Importance of the Research Achievements

グリコーゲンはヒトにおけるエネルギー貯蓄の重要な形態であり、肝臓は骨格筋とともにグリコーゲンの重要な貯蓄器官である。肝臓糖代謝の測定は血液検査による血糖値やグルカゴンおよびインスリンなどのホルモン濃度による測定が一般的であり、これまでの画像法による定量評価は困難である。今回の研究により臨床に使用される3T MRI機器を用いて、GlycoCESTによるグリコーゲンの同定が可能であることが示された。本撮像法の確立は安価で安全な肝臓糖代謝測定法の新規技術となり、臨床的に有用であると考えられる。

Research Products

• [Journal Article] Conspicuity of Malignant Liver Tumors on Diffusion-Weighted Imaging With Short tau Inversion Recovery After Gadolinium Ethoxybenzyl Diethylenetriaminepentaacetic Acid Administration. (2019)
  • Author(s): Takashi Iwanaga, Yoshihiko Fukukura, Tomonori Saito, Masashi Sasaki, Yuichi Kumagae, Koji Takumi, Hiroto Hakamada, Takuro Fujisaki, Yasumasa Saigo, Takashi Yoshiura
  • Journal Title: Journal of Magnetic Resonance Imaging Volume: 49 Issue: 2 Pages: 565-573
  • DOI: 10.1002/jmri.26196
  • Peer Reviewed
• [Presentation] Effect of Saturation Pulse Strength and Duration on GlycoCEST Imaging: -an Experimental Study in ex vivoBovine Liver- (2020)
  • Author(s): Takashi Iwanaga, Shinji Mawatari, Hirokazu Otsuka, Yasumasa Saigo
  • Organizer: 第76回 日本放射線技術学会総会学術大会
• [Presentation] Effect of saturation pulse strength and duration on APT and GlycoCEST imagings: a phantom study (2018)
  • Author(s): Takashi Iwanaga
  • Organizer: 第46回 日本磁気共鳴医学会大会