Li Xin, Yang Huifang, Yan Jiaqing, Wang Xingran, Li Xiaoli, Yuan Yi
Institute of Electrical Engineering, Yanshan University, Qinhuangdao, China.
College of Electrical and Control Engineering, North China University of Technology, Beijing, China.
Front Neurosci. 2019 Apr 2;13:287. doi: 10.3389/fnins.2019.00287. eCollection 2019.
Low-intensity pulsed ultrasound stimulation (LIPUS) can inhibit seizures associated with temporal lobe epilepsy (TLE), which is the most common epileptic syndrome in adults and accounts for more than half of the cases of intractable epilepsy. Electroencephalography (EEG) signal analysis is an important method for studying epilepsy. The nonlinear dynamics of epileptic EEG signals can be used as biomarkers for the prediction and diagnosis of epilepsy. However, how ultrasound modulates the nonlinear dynamic characteristics of EEG signals in TLE is still unclear. Here, we used low-intensity pulsed ultrasound to stimulate the CA3 region of kainite (KA)-induced TLE mice, simultaneously recorded local field potentials (LFP) in the stimulation regions before, during, and after LIPUS. The nonlinear characteristics, including complexity, approximate entropy of different frequency bands, and Lyapunov exponent of the LFP, were calculated. Compared with the control group, the experimental group showed that LIPUS inhibited TLE seizure and the complexity, approximate entropy of the delta (0.5-4 Hz) and theta (4-8 Hz) frequency bands, and Lyapunov exponent of the LFP significantly increased in response to ultrasound stimulation. The values before ultrasound stimulation were higher ∼1.87 (complexity), ∼1.39 (approximate entropy of delta frequency bands), ∼1.13 (approximate entropy of theta frequency bands) and ∼1.46 times (Lyapunov exponent) than that after ultrasound stimulation ( < 0.05). The above results demonstrated that LIPUS can alter nonlinear dynamic characteristics and provide a basis for the application of ultrasound stimulation in the treatment of epilepsy.
低强度脉冲超声刺激(LIPUS)可抑制与颞叶癫痫(TLE)相关的癫痫发作,TLE是成人中最常见的癫痫综合征,占难治性癫痫病例的一半以上。脑电图(EEG)信号分析是研究癫痫的重要方法。癫痫EEG信号的非线性动力学可作为癫痫预测和诊断的生物标志物。然而,超声如何调节TLE中EEG信号的非线性动态特征仍不清楚。在此,我们使用低强度脉冲超声刺激红藻氨酸(KA)诱导的TLE小鼠的CA3区,同时在LIPUS刺激前、刺激期间和刺激后记录刺激区域的局部场电位(LFP)。计算了LFP的非线性特征,包括复杂度、不同频段的近似熵和Lyapunov指数。与对照组相比,实验组显示LIPUS抑制了TLE癫痫发作,并且在超声刺激下,LFP的复杂度、δ(0.5 - 4 Hz)和θ(4 - 8 Hz)频段的近似熵以及Lyapunov指数显著增加。超声刺激前的值比超声刺激后高约1.87倍(复杂度)、约1.39倍(δ频段近似熵)、约1.13倍(θ频段近似熵)和约1.46倍(Lyapunov指数)(P < 0.05)。上述结果表明,LIPUS可改变非线性动态特征,并为超声刺激在癫痫治疗中的应用提供了依据。