Implantable Vagus Nerve Stimulation Modulation of Coeruleus-Norepinephrine Network for Mild-Moderate AD Patients

This project plans to recruit 6 patients with Mild-Moderate Alzheimer's disease. They were randomly divided into vagus nerve active stimulation group and sham stimulation group, to receive vagus nerve stimulator implantation. 2 weeks after implantation, the active group will start the treatment for 12 weeks, and the stimulator of the shame group will be turned off for 12 weeks. Before treatment, cognitive assessment, head MRI and PET examination of norepinephrine distribution were completed. Side effects and adverse events were assessed at 6 weeks, 10 weeks, and 14 weeks, and cognitive assessment, head MRI and PET examination of norepinephrine distribution was also performed at the 14th week, Then, the true stimulation group continued to be turned on for 12 weeks, and the sham group turned on the stimulator to start the treatment for 12 weeks. cognitive assessment, head MRI and PET examination of norepinephrine distribution were also performed at 26 weeks.