Developmental profile of callosal myelination in children with refractory epilepsy

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K09402
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 56010:Neurosurgery-related
• Research Institution: Department of Clinical Research, National Hospital Organization Nagasaki Medical Center
• Principal Investigator: Ono Tomonori 独立行政法人国立病院機構(長崎医療センター臨床研究センター), 脳神経外科, 脳神経外科医長 (10393456)
• Co-Investigator(Kenkyū-buntansha): 本田 涼子 独立行政法人国立病院機構(長崎医療センター臨床研究センター), 小児科, 医師 (70457555)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 髄鞘化 / 大脳白質 / 脳梁 / ミエリン塩基性タンパク / MRI / てんかん

Outline of Final Research Achievements

Although MRI is used to observe the development of myelination of the brain, we do not have direct evidence in humans. Myelin basic protein (MBP) is a major protein involved in myelination that can be measured by biological techniques such as the ELISA method. This prospective study correlated age-related changes in MRI-diffusion tensor imaging (DTI) and the amount of MBP in the corpus callosum obtained from patients with refractory epilepsy who underwent callosotomy. Patients aged 8-267 months were included. The apparent diffusion coefficients (ADC) of the corpus callosum were individually averaged by using MRI-DTI (0.65-1.3 x 10-3 mm2/s). White-matter tissues were intraoperatively collected, and ELISA detected 9.4-22.9 pg/mL of MBP in the tissues. Finally, these data could be individually compared among 12 patients, and the amount MBP was negatively correlated with those of ADC (R = -0.75).
The results provide a direct correlation between age-related changes on MRI and myelination.

Free Research Field

小児神経学

Academic Significance and Societal Importance of the Research Achievements

脳の発達における主要な特徴の1つは髄鞘形成である。MRI は加齢に伴う白質の変化を視覚化し、それは髄鞘化によると説明されているが、ヒトにおける直接的な証拠はなかった。本前向き研究は小規模なパイロット研究ではあるが、MRI-DTI で同定されたヒトの脳梁における成長に伴う信号変化が、大脳白質線維のMBP 含有量の増加と強く相関し、髄鞘形成を表しているという初めての直接的な証拠を提供するものである。これにより、脳発達を可視化する検査としてのMRIの妥当性が示され、今後の診断技術にも貢献できると考える。