Improvement of dementia diagnosis accuracy by FDG using PET / MR

2018 Fiscal Year Final Research Report

• Project/Area Number: 15K09964
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Radiation science
• Research Institution: Fukushima Medical University
• Principal Investigator: Nambu Takeyuki 福島県立医科大学, 公私立大学の部局等, 助手 (60706662)
• Co-Investigator(Kenkyū-buntansha): 久保 均 福島県立医科大学, 公私立大学の部局等, 教授 (00325292) ; 伊藤 浩 福島県立医科大学, 公私立大学の部局等, 教授 (20360357)
• Research Collaborator: MATSUBARA keisuke ; INOMATA takato
• Project Period (FY): 2015-04-01 – 2019-03-31
• Keywords: PET/MR / 減弱補正 / 体動補正 / 部分容積効果 / 核医学 / PET定量 / MRI

Outline of Final Research Achievements

In this study, we examined whether the diagnostic accuracy of dementia by FDG could be improved by using the integrated PET / MR scanner or by focusing on three distinctive points.
First of all, although it is a partial volume effect for cortical separation, since the MR image is an image suitable for cortical separation, the accuracy has been improved compared to the case of using CT images. Second, with regard to the effect of motion correction by true simultaneous collection, the effect appeared in the data that separated the cortex when there was motion. However, it was confirmed that the influence was reduced to the same level as the case without body movement when body movement correction was performed. Third is the depiction of bones used for attenuation correction, but the UTE method alone did not complete bone depiction. It was also confirmed that over-correction occurs when the pattern method is combined. Therefore, further improvement was needed.

Free Research Field

核医学技術学　PET検査技術学　医用画像工学

Academic Significance and Societal Importance of the Research Achievements

PET/MR装置が世に登場してから10年弱が経過している．この装置が従来のPET/CT装置に比べての優位性については様々な議論があった．その中で我々はPET/MR装置の大きな３つの特徴に着目し，近年先進医療Bに採択されたFDG-PETによる認知症診断との親和性について検討した．
その結果，PET/MR装置を使用することで皮質におけるFDGの定量精度が向上することが示されたが，逆に減弱補正についてはPET/CT装置と同等の補正が行われていないことが確認できた．
しかしこの減弱補正の問題が解決すれば他の優位性が際立ち，PET/MR装置の高い定量性が認知症の早期および病期診断の一助になると考えられる．