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.
A randomized controlled clinical study will be conducted in Xuanwu Hospital of Capital Medical University. This study initially explore the effect of selective vagus nerve(C fiber) stimulation on mild-to-moderate AD patients, in order to regulate the activity of the locus coeruleus-norepinephrine network, and to observe the improvement of cognitive function and memory function. We aim to evaluate the efficacy and safety of minimally invasive selective vagus nerve stimulation in the treatment of mild-to-moderate AD patients, to clarify the effective mechanism, and to provide an effective clinical treatment strategy.