解码矛盾的BOLD反应,以超超声波刺激与并发的光声磁共振成像
Yi Chen1,2, Zhenyue Chen3, Hector Estrada1,2
1Institute for Biomedical Engineering and Institute of Pharmacology and Toxicology, University of Zürich, Zürich, Switzerland.
Science advances
|October 31, 2025
概括
聚焦的横超声波刺激 (TUS) 在小鼠中显示出矛盾的负 BOLD 信号. 这种新的混合成像系统 (OMRITUS) 揭示了复杂的血液动力学变化,有助于精确的神经调节的发展.
科学领域:
- 神经科学是一个神经科学.
- 生物医学工程 生物医学工程
- 医疗成像医学成像
背景情况:
- 专注的横超声波刺激 (TUS) 为大脑疾病提供了精确的非侵入性神经调节.
- 功能性磁共振成像 (fMRI) 常用于研究TUS效应,但其机制尚不清楚.
- 了解TUS诱导的血液动力学变化对于优化神经调节治疗至关重要.
研究的目的:
- 开发和验证一种混合系统,用于同时对TUS进行光声学和磁共振成像 (OMRITUS).
- 在小鼠大脑中全面描述TUS引起的血液动力学反应.
- 调查TUS期间BOLD信号的生理基础.
主要方法:
- 同时使用光声学断层扫描 (OT) 和磁共振成像 (MRI) 来实时监测TUS效应.
- 多谱OT用于量化氧化和脱氧血红蛋白的变化.
- 用BOLD fMRI评估激活皮质区域中的血液动力学反应.
主要成果:
- 在老鼠大脑中,OMRITUS成功捕获了TUS期间同时发生的血液动力学变化.
- 在TUS激活的皮质区域观察到矛盾的负BOLD信号.
- 光声学数据显示,总血红蛋白增加,脱氧血红蛋白增加更大,这表明负BOLD的分子基础.
结论:
- 欧姆里图斯系统为研究TUS-血液动力学相互作用提供了一个全面的工具.
- 研究结果表明,在TUS期间神经活动和血液动力学之间存在复杂的相互作用,这可能解释了负面的BOLD信号.
- 这项研究为更精确,更有效的基于TUS的神经调节疗法铺平了道路.
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