To analyze the correlation between the preoperative resting-state electroencephalogram (EEG) features and cognitive function in patients with severe vertebrobasilar artery (VBA) stenosis, explore the changes in EEG features after percutaneous transluminal angioplasty and stenting (PTAS), and further infer the potential mechanism of early brain network remodeling after interventional treatment.

Thirty-three patients with severe VBA stenosis who underwent PTAS in the Neurology Department of Sichuan Provincial People's Hospital from October 2023 to October 2024 were selected as the case group. A control group was selected from the department's database at a 1∶1 ratio, matching the case group in terms of age and gender from 2023 to 2024. The cognitive function of both groups was evaluated using the mini-mental state examination (MMSE) and the Montreal cognitive assessment (MoCA) before the operation. The case group underwent resting-state EEG examinations before and one week after PTAS. Quantitative analysis was conducted to compare the changes in power spectra and brain network topological properties in different frequency bands before and after the operation. Correlation analysis was performed between the quantitative EEG indicators of the case group before the operation and their cognitive scores to explore the potential association between EEG physiological characteristics and cognitive status.

There were statistically significant differences in the total scores and sub-scores of MMSE (memory, orientation, language, and visuospatial ability) and MoCA (visuospatial and executive function, naming, reading, language, abstraction, delayed recall, and orientation) between the two groups (P<0.05). One week after the operation, the power of EEG activity in the α, β, and γ frequency bands decreased compared with that before the operation, while the shortest path length of the brain network in the α, β, and γ frequency bands significantly increased, and the clustering coefficient, global efficiency, and local efficiency in the β and γ frequency bands significantly decreased (P<0.05). The network properties in the θ frequency band were significantly correlated with cognitive scores (MMSE and MoCA) (P<0.05).

There are significant changes in EEG activity in patients with severe VBA stenosis after PTAS. The weakening of low-frequency δ band oscillations may indicate changes in cognitive function in the short term after PTAS, and promote brain recovery by enhancing brain region connections. Quantitative EEG analysis provides a new theoretical basis for postoperative cognitive function monitoring and rehabilitation treatment in patients with severe VBA stenosis.