The Effectiveness Research Of Domestic Vagus Nerve Stimulators In Patients With Intractable Epilepsy

Objective: 1.We contrast the change of seizure control before and after the Vagus Nerve Stimulation therapy in order to study the effectiveness of domestic vagus nerve stimulators in patients with intractable epilepsy.2.Using brain network analysis methods,we attempt to explore the mechanism of Vagus Nerve Stimulation therapy in treating intractable epilepsy.Method: 1.We mainly measure the changes in seizure frequency between pre-and twelve months post-VNS Therapy and classify the patients in terms of Mc Hugh scale.Then perform the Wilcoxon test between before and after the Vagus Nerve Stimulation therapy.2.For the sake of exploring the VNS Therapy mechanism,we measured the changes in resting state brain networks between pre-and twelve months post-VNS Therapy,from the perspective of regional and global variations by regional homogeneity(Reho)and large scale Functional connectives respectively.The resting state Functional Magnetic Resonance Imaging(Fmri)methods were mainly adopted in this report.Results: 1.Compared with Pre-VNS therapy,the seizure frequency reduced significantly after twelve months VNS therapy.In addition,according to Mc Hugh scale,5 patients(17%)were ranked the fist level;12 patients(41%),8 cases(28%)and 3 patients(10%)were classified as the second,third,and fifth level.There is only one case(4%)in the fourth level.2.Compared to the pre-VNS Therapy,the after-VNS Therapy top 5% Reho values change greatly in the medial prefrontal cortex(m PFC),and posterior cingulate cortex(PCC)regions.Networks connectivity study showed that the connectives among nodes among 5 patients(83%)were enhanced both in the regional and global brain cortex,though there was some decreased connectivity changes in one case.Conclusion: 1.Domestic vagus nerve stimulators is effective in treating intractable epilepsy,and it is consistent with the seizure reduction rate reported in the foreign literatures.2.In the perceptive of resting state brain networks,VNS therapy can strengthen the brain networks connectivity,and modulate the brain cortex activation of default mode networks and salience networks.Keeping the balance between default mode networks and salience networks may be the underlining mechanism of VNS therapy in treating intractable epilepsy.