Intraoperative visualization of human cortical activation using flavoprotein imaging

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K10887
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Neurosurgery
• Research Institution: Niigata University
• Principal Investigator: Makoto Oishi 新潟大学, 脳研究所, 准教授 (00422593)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: optical imaging / human brain / monitoring

Outline of Final Research Achievements

In the present study, we set out to detect neural activity using intraoperative flavoprotein fluorescence imaging (iFFI), which involves visualization of fluorescence changes derived from aerobic energy metabolism. In 7 brain tumor patients, neural activities were induced by direct electrical stimulation of surrounding cortex, and iFFI and intraoperative PDI (iPDI) were performed. Optical response of iFFI demonstrated a biphasic time course in which a short time increase in fluorescence was followed by a negative fluorescence change. By iPDI, only a relatively long-lasting negative signals were observed. The positive component of iFFI signals appeared the fastest and were most localized. These results suggest that detection of the positive component in iFFI enables earlier and more accurate detection of neural activity, potentially having profound influence on intraoperative detection of neural activity.

Free Research Field

脳神経外科

Academic Significance and Societal Importance of the Research Achievements

脳神経外科の手術においてさらなる安全性と確実性を追求するために，脳機能および脳解剖の新規イメージング法や神経生理学的手法を用いたモニタリング法にこだわった新しい手術支援法の確立に常に取り組んできた．その中でも，術中の「神経活動領域の可視化」は，脳神経外科医にとって究極の手術支援方法となりうるが，未だかつて実現した報告はない．本研究は，実験レベルで特別な薬剤を使用せずに神経組織の活動時に自然発現するフラビン蛋白を特殊波長で蛍光観察するフラビン蛍光法をヒト大脳に応用し，新たな手術支援法として確立できないかチャレンジしたものである．