New method of evaluating neurological damage after acute encephalitis using quantitative EEG analysis

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K09085
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 55060:Emergency medicine-related
• Research Institution: Nihon University
• Principal Investigator: MORITA Akihiko 日本大学, 医学部, 兼任講師 (80547117)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 急性脳炎・脳症 / 定量脳波解析 / functional connectivity / 神経損傷 / 神経救急

Outline of Final Research Achievements

We exploded novel method of evaluating neurological damage after acute encephalitis using quantitative EEG technique. Patients with herpes encephalitis, anti-N-methyl-d-aspartate (NMDA) receptor encephalitis and aseptic meningitis were enrolled and findings of quantitative EEG (QEEG), S100B, neuron specific enolase (NSE) and glial fibrillary acid protein (GFAP) levels in cerebrospinal fluid (CSF), and outcomes were compared between three groups.
In HSE group, the slowing of EEGs and disruption of functional connectivity were more obvious. Levels of CSF S100B, NSE and GFAP were not significantly different between three groups.
Multiple logistic regression analysis revealed that spectral ratio was significantly related to poor neurological outcome (modified Rankin scale 0-1 versus 2-6; 95% confidence interval, 0.000023-0.425; p=0.021).

Free Research Field

臨床神経学

Academic Significance and Societal Importance of the Research Achievements

定量脳波を用いた急性脳炎・脳症の神経損傷の新たな評価指標の探索を行い、単純ヘルペス脳炎では急性期実施脳波にて有意な徐波化と脳内機能結合の低下域の拡大を認め、急性脳炎・脳症の転帰不良と脳波の徐波化との関連が有意であることを明らかにした。デジタル脳波計を用いた脳波検査は保険収載されており、全身状態不良の患者でもベッドサイドで安全に実施可能である。本研究で用いた高速フーリエ変換によるパワースペクトル解析やコヒーレンス解析は、定量脳波解析の手法として既に確立されていることから、この検査法は急性脳炎・脳症患者における神経損傷の客観的な評価指標となり、新たな治療の開発に貢献すると考える。