Functional changes of postmortem brain and its effects on MRI image ocntrast

2018 Fiscal Year Final Research Report

• Project/Area Number: 17K17891
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Medical Physics and Radiological Technology; Medical and hospital managemen
• Research Institution: The University of Tokushima (2018); Shimane University (2017)
• Principal Investigator: NISHIYAMA Yuichi 徳島大学, 大学院医歯薬学研究部(医学域), 助教 (80730598)
• Project Period (FY): 2017-04-01 – 2019-03-31
• Keywords: 死亡時画像診断 / MRI / CT / 死後変化 / 脳 / SOD / 鉄

Outline of Final Research Achievements

This study focued on the metal deposition in the postmortem brain as functional change of the tissue, and investigated its influence in generating MRI image contrast of postmortem rat brain. Putamen and thalamus showed a significant reduction of signal intensity in a postmortem T2-weighted MRI image. We assessed the expression of metal-containing enzyme, superoxide dismutase (SOD) and the iron deposition in these brain regions by histopathological staining，and no significant increase of metal deposition was observed. These findings suggested that other contributing factors except metal deposition and organic postmortem change exist for generating characteristic MRI image contrast of the postmortem brain.

Free Research Field

放射線科学，放射線生物学

Academic Significance and Societal Importance of the Research Achievements

死後画像と生体画像の画像信号の違いは主として，器質的な死後変化が原因であるとされている。本研究では，金属成分の沈着や，あるいは脳浮腫などの典型的な器質的死後変化とは異なる何らかが，死後脳MRIにおける特徴的な画像コントラストを生じさせる要因として存在する可能性が明らかになった。本研究で得られた成果は，死後脳組織に生じる死後変化の詳細な解明，さらには死後脳MRI画像の読影方法を構築するうえでの一助になると期待される。