Authors :
Presenting Author: Yicong Lin, MD – Xuanwu Hospital, Capital Medical University
Xinyan Liu, MD – School of Biological Science and Medical Engineering, Beihang University; Xiaohong Qi, MD – Pediatrics – Xuanwu Hospital, Capital Medical University; Wenwen Shen, MD – Pediatrics – Xuanwu Hospital, Capital Medical University; Xuerong Leng, MD – Pediatrics – Xuanwu Hospital, Capital Medical University; Xiating Zhang, MD – Neurology – Xuanwu Hospital, Capital Medical University; Liping Zhang, MD – Pediatrics – Xuanwu Hospital, Capital Medical University; Yuexin Zhang, BS – Neurology – Xuanwu Hospital, Capital Medical University; Xuan Zhao, BS – Pediatrics – Xuanwu Hospital, Capital Medical University; Jicong Zhang, MD – School of Biological Science and Medical Engineering – Beihang University; Yuping Wang, MD – Neurology – Xuanwu Hospital, Capital Medical University; Yicong Lin, MD – Neurology – Xuanwu Hospital, Capital Medical University
Rationale:
Landau-Kleffner syndrome (LKS), also known as acquired epileptic aphasia, is a rare epileptic syndrome which may lead to lifelong language impairment. Transcranial direct current stimulation (tDCS) and repetitive transcranial magnetic stimulation (rTMS) are non-invasive brain stimulation techniques, which could reduce the frequency of seizures. We used simultaneous tDCS-rTMS to treat patients with LKS preliminarily.
Methods:
We included two patients diagnosed with LKS. Each patient received 2×20 min treatment daily for 15 days. The >rTMS (1Hz) stimulation target and cathodal electrode (1.5mA) was determined over the center of clustered dipoles. The anodal electrode was placed in the contralateral orbital frontal region. We also established the brain network based on phase transfer entropy to explore the therapeutic mechanisms.
Results:
Patient 1 was a 9-year-old girl, ambidexterity. She presented with epilepsy for six years and severe language regression for two years. The patient received tDCS-rTMS treatment. The language function improved significantly, and no seizure was recorded. The Peabody picture vocabulary test score increased from 84 to 112. Patient 2 was a right-handed 8-year-old girl. She presented with five year history of language regression. She received only tDCS because she could not cooperate with rTMS. After treatment, she could follow instructions, but was still poor with infrequent active speech. We analyzed the functional connectivity of Patient 1. In left hemisphere (LH), the difference was mainly embodied alpha, beta and gamma band (Fig. 1). In alpha band, the information inflow to left supramarginal gyrus (SMG) increased. In beta band, the information inflow from pars opercularis and pars orbitalis to posterior superior temporal gyrus (pSTG) increased. In gamma band, the information inflow from pSTG to pars orbitalis and those from pSTG to angular gyrus increased. In right hemisphere (RH), the difference was embodied beta band, the information inflow from SMG and pars opercularis to the pars orbitalis increased (Fig. 2). In alpha band, more information flow into the left. In beta band, the information flow into the left pSTG is significantly higher than right. In gamma band, the information outflow from left pSTG increased significantly.
Conclusions:
This study preliminarily showed that tDCS-rTMS therapy was safe to be tolerated in pediatric patients and was likely to improve language function in patients with LKS. Stimulating right inferior parietal lobe by tDCS-rTMS not only affect the RH language network, but also profoundly affect the LH network which involved in language perception, processing, and understanding.
Funding:
This work is supported by Beijing Natural Science Foundation (Grant Number: Z200024), Beijing Hospital Authority Cultivation Projec (PX2023032) and National Support Provincial Major Disease Medical Services and Social Capability Enhancement Project.