Cranial nerve stimulation to treat seizure disorders

Abstract

A method includes determining a measurement indicative of a synchrony between one or more regions of a patient's autonomic nervous system (e.g., the NTS) and one or more regions of the patient's central nervous system (e.g., the thalamus, the cortex) based on body parameter data. The method also includes adjusting a cranial nerve stimulation parameter based on the measurement.

What is claimed is: 
     
         1 . A method comprising:
 determining that a patient is experiencing a seizure; and   in response to determining that the patient is experiencing a seizure, applying one or more microburst stimulation signals to a cranial nerve of the patient, the microburst stimulation signals adapted to change a level of synchrony between neural activity of one or more regions of an autonomic nervous system of the patient and one or more regions of the central nervous system of the patient.   
     
     
         2 . The method of  claim 1 , wherein the one or more regions of the autonomic nervous system comprise one or more regions of a nucleus tractus solitarii of the patient, and wherein the one or more regions of the central nervous system comprise one or more regions of a cortex of the patient, a thalamus of the patient, or both. 
     
     
         3 . The method of  claim 1 , wherein the cranial nerve is a vagus nerve. 
     
     
         4 . The method of  claim 1 , wherein the one or more microburst stimulation signals are applied to the cranial nerve of the patient until the synchrony satisfies a threshold synchrony value. 
     
     
         5 . The method of  claim 1 , wherein the one or more microburst stimulation signals are applied to the cranial nerve until a rate of change of the synchrony responsive to the one or more microburst signals satisfies a threshold rate of change value. 
     
     
         6 . The method of  claim 1 , wherein determining that the patient is experiencing a seizure comprises determining that the patient is experiencing the seizure based on body parameter data collected from one or more sensors implanted in the patient and/or external to the patient. 
     
     
         7 . The method of  claim 6 , wherein the one or more sensors comprise one or more sensors implanted in at least one of the autonomic nervous system or the central nervous system. 
     
     
         8 . The method of  claim 6 , wherein the one or more sensors comprise one or more sensors placed on a surface of a body of the patient. 
     
     
         9 . An implantable medical device (IMD) comprising:
 a therapy delivery unit;   a processor; and   a memory including instructions that are executable by the processor to:
 determine that a patient is experiencing a seizure; and 
 in response to determining that the patient is experiencing a seizure, apply one or more microburst stimulation signals to a cranial nerve of the patient by the therapy delivery unit, the microburst stimulation signals adapted to change a level of synchrony between neural activity of one or more regions of an autonomic nervous system of the patient and one or more regions of the central nervous system of the patient. 
   
     
     
         10 . The IMD of  claim 9 , wherein the one or more regions of the autonomic nervous system comprise one or more regions of a nucleus tractus solitarii of the patient, and wherein the one or more regions of the central nervous system comprise one or more regions of a cortex of the patient, a thalamus of the patient, or both. 
     
     
         11 . The IMD of  claim 9 , wherein the cranial nerve is a vagus nerve. 
     
     
         12 . The IMD of  claim 9 , wherein the instructions are executable by the processor to apply the one or more microburst stimulation signals to the cranial nerve of the patient until the synchrony satisfies a threshold synchrony value. 
     
     
         13 . The IMD of  claim 9 , wherein the instructions are executable by the processor to apply the one or more microburst stimulation signals to the cranial nerve of the patient until a rate of change of the synchrony responsive to the one or more microburst signals satisfies a threshold rate of change value. 
     
     
         14 . The IMD of  claim 9 , further comprising one or more sensors configured to be implanted in the patient and/or external to the patient, and wherein the instructions are executable by the processor to determine that the patient is experiencing the seizure based on body parameter data collected from the one or more sensors. 
     
     
         15 . The IMD of  claim 14 , wherein the one or more sensors comprise one or more sensors configured to be implanted in at least one of the autonomic nervous system or the central nervous system. 
     
     
         16 . The IMD of  claim 14 , wherein the one or more sensors comprise one or more sensors configured to be placed on a surface of a body of the patient. 
     
     
         17 . A computer-readable storage medium storing instructions thereon that, when executed by a processor, cause an implantable medical device (IMD) to:
 determine that a patient is experiencing a seizure; and   in response to determining that the patient is experiencing a seizure, apply one or more microburst stimulation signals to a cranial nerve of the patient, the microburst stimulation signals adapted to change a level of synchrony between neural activity of one or more regions of an autonomic nervous system of the patient and one or more regions of the central nervous system of the patient to a level of synchrony indicative of a non-seizure state.   
     
     
         18 . The computer-readable storage medium of  claim 17 , wherein the instructions further cause the IMD to apply the one or more microburst stimulation signals to the cranial nerve of the patient until the synchrony satisfies a threshold synchrony value indicative of the non-seizure state. 
     
     
         19 . The computer-readable storage medium of  claim 17 , wherein the instructions further cause the IMD to apply the one or more microburst stimulation signals to the cranial nerve of the patient until a rate of change of the synchrony responsive to the one or more microburst signals satisfies a threshold rate of change value indicative of the non-seizure state. 
     
     
         20 . The computer-readable storage medium of  claim 17 , wherein the instructions further cause the IMD to determine that the patient is experiencing the seizure based on body parameter data collected from one or more sensors implanted in the patient and/or external to the patient.