Systems and methods for establishing a nerve block

Abstract

A nerve cuff for establishing a nerve block on a nerve can have a cuff body with a channel for receiving a nerve, a reservoir for holding a drug, and an elongate opening slit extending the length of the cuff body that can be opened to provide access to the channel and can be closed to enclose the cuff body around the nerve. The nerve cuff can also include an electrode for detecting and measuring electrical signals generated by the nerve. A controller can be used to control delivery of the drug based on the electrical signals generated by the nerve.

What is claimed is: 
     
         1 . A method of calibrating a clock of an implantable neurostimulator device, the method comprising:
 keeping time using a first clock of the implantable neurostimulator device, wherein the first clock runs continuously and is operating based upon a reference voltage generated within a circuitry of the implantable neurostimulator device;   triggering a calibration protocol;   turning on a second clock within the implantable neurostimulator device;   calibrating the first clock based on the second clock to correct for thermally dependent time drift; and   turning off the second clock.   
     
     
         2 . The method of  claim 1 , wherein the reference voltage is associated with an RC circuit to produce a time reference. 
     
     
         3 . The method of  claim 1 , wherein an event triggers the calibration protocol, wherein the event is a period of time determined by the first clock. 
     
     
         4 . The method of  claim 3 , wherein the period of time is few hours, a day, a few days, a week, a couple of weeks, a month, a few months, or a year. 
     
     
         5 . The method of  claim 1 , wherein an event triggers the calibration protocol, wherein the event is a change in the reference voltage above a threshold value. 
     
     
         6 . The method of  claim 1 , wherein the second clock comprises a piezoelectric clock. 
     
     
         7 . An implantable neurostimulator device comprising:
 a first clock configured to keep time within the implantable neurostimulator device; and   a second clock having more accurate time-keeping capabilities than the first clock, wherein the second clock is configured to be in an off or idle mode while the first clocking is running; and   a control circuitry configured to be triggered by an event such that upon triggering, the control circuitry turns the second clock on, uses the second clock to calibrate the first clock, and then turns the second clock off.   
     
     
         8 . The implantable neurostimulator device of  claim 7 , wherein the first clock is configured to count time based upon a reference voltage generated by the control circuitry. 
     
     
         9 . The implantable neurostimulator device of  claim 7 , wherein the second clock comprises a piezoelectric crystal oscillator. 
     
     
         10 . The implantable neurostimulator device of  claim 7 , wherein the event comprises a preset signal programmed into the control circuitry. 
     
     
         11 . The implantable neurostimulator device of  claim 10 , wherein the event is a temperature change. 
     
     
         12 . The implantable neurostimulator device of  claim 10 , wherein the preset signal is based on a set length of time. 
     
     
         13 . The implantable neurostimulator device of  claim 10 , wherein the preset signal is a voltage value above a certain threshold. 
     
     
         14 . A leadless, implantable microstimulator device comprising:
 a housing;   at least two electrically conductive contacts disposed on the housing;   a microcontroller configured to control stimulation of a vagus nerve from the electrically conductive contacts;   a first clock configured to keep time; and   a second clock having more accurate time-keeping capabilities than the first clock, wherein the second clocking is configured to periodically calibrate the first clock.   
     
     
         15 . The leadless, implantable microstimulator device of  claim 14 , wherein the second clocking module is configured to be in an idle mode when not calibrating the first clock. 
     
     
         16 . The leadless, implantable microstimulator device of  claim 14 , further comprising:
 a resonator comprising a coil and a capacitor configured to resonate at a predetermined frequency range, wherein an electronic assembly is configured to receive power from the resonator to charge a battery.   
     
     
         17 . The leadless, implantable microstimulator device of  claim 14 , wherein a control circuitry is configured to be triggered by an event such that upon triggering, the control circuitry turns the second clock on, uses the second clock to calibrate the first clock, and then turns the second clock off. 
     
     
         18 . The leadless, implantable microstimulator device of  claim 17 , wherein the control circuitry is configured to correct a time drift of the first clock after a calibration is performed. 
     
     
         19 . The leadless, implantable microstimulator device of  claim 17 , wherein the event comprises a preset signal programmed into the control circuitry. 
     
     
         20 . The leadless, implantable microstimulator device of  claim 19 , wherein the preset signal is based on a set length of time, a voltage value threshold, or a current value threshold.