The great reset: Transcranial pulse stimulation reduces global EEG-entropy in Alzheimer's Disease

Abstract

Abstract Background: Transcranial Pulse Stimulation (TPS) is a new therapy that uses shockwaves for the treatment of Alzheimer's Disease (AD). In humans, there is first evidence for beneficial clinical effects after a series of six TPS sessions. Magnetic resonance imaging studies suggest up-regulation of memory networks as well as increased cortical thickness after stimulation. Effects on oscillatory electrical brain activity measured with resting state electroencephalography (EEG) have not been reported so far. Methods: A consecutive number of four pilot TPS-treated AD-patients was examined. TPS-naïve resting EEGs were recorded before treatment and compared with EEG-recordings directly after first stimulation. All patients received 4Hz TPS of about 6000 pulses of 0.2 mJ/mm2 (navigated bifrontally, biparietally, bitemporally and praecuneus) using the Neurolith System (Storz Medical). Frontal, parietal, central and temporal channel clusters were analyzed with regard to their alpha, theta delta and gamma power and for a measure of Tsallis entropy. Results: The immediate effect after first TPS on grand-average EEG resting state showed an increase of power in all frequency bands and for total power, although a significant difference between pre- and post-stimulation was not revealed due to power variability. However, the grand-average across patients and channels of Tsallis entropy showed a significant reduction after a single stimulation session. Discussion / Conclusion: Limited due to a high variability (and possibly due to underpower) we found power increase across frequency bands and channels which failed signifance. On the other hand Tsallis entropy was a more sensitive measure for change on EEG activity after stimulation. This might reflect a global reset of uncoordinated and thus pathological neural activity after TPS stimulation. More measurements should be added including longitudinal serial recordings over the treatment course of six sessions with correlations of clinical treatment effects. Keywords: transcranial pulse stimulation, shock wave , Alzheimer, EEG