Systems, devices and methods that affect neural tissue through the delivery of a pulsed radio frequency signal generated by an implantable medical device

Abstract

Radio frequency (RF) energy is transmitted through the application of a RF signal to an external RF energy interface, where the RF signal oscillates at a frequency in an energy transmission band. The transmitted RF energy is received at an implanted medical device, and energy derived from the received RF energy is stored in a direct current (DC) energy storage component of the device. A therapeutic output signal is generated from the stored energy and delivered by the implantable medical device to a patient through one or more electrodes. The therapeutic output signal is configurable to provide either one of RF stimulation therapy and RF ablation therapy, and comprises pulses of an RF signal oscillating at a frequency in a therapy band that is greater than the energy transmission band.

What is claimed is: 
     
         1 . A pain management system for use in conjunction with an orthopedic implant device having a hardware component, the system comprising:
 an external device configured to transmit radio frequency (RF) energy through the application of a RF signal to an external RF energy interface, wherein the RF signal oscillates at a frequency in an energy transmission band; and   an implantable medical device comprising:
 one or more electrodes configured to be implanted in, on, or adjacent a target area of nerves, 
 an implantable RF energy interface configured to receive energy from the external RF energy interface over a wireless energy link, 
 an energy storage component configured to store the energy, and 
 a RF therapy controller coupled to the energy storage component and the one or more electrodes, the RF therapy controller configured to: 1) generate a therapeutic output signal from the stored energy, the therapeutic output signal configurable to provide either one of RF stimulation therapy and RF ablation therapy, and comprising pulses of an RF signal oscillating at a frequency in a therapy band that is greater than the energy transmission band, and 2) deliver the therapeutic output signal to one or more of the plurality of electrodes, and 
 a housing configured to enclose the RF therapy controller, and to be mechanically coupled to the hardware component of the orthopedic implant device. 
   
     
     
         2 . The system of  claim 1 , wherein the energy transmission band is in a range of 40-60 KHz and the therapy band is in a range of 300-500 KHz. 
     
     
         3 . The system of  claim 1 , wherein the external device is configured to transmit continuous RF energy through the application of a continuous RF signal to the external RF energy interface. 
     
     
         4 . The system of  claim 1 , wherein the external device is further configured to transmit RF energy through the application of a RF signal that oscillates at a frequency in a diathermy band less than the therapy band. 
     
     
         5 . The system of  claim 4 , wherein the diathermy band is in a range of 40-60 KHz. 
     
     
         6 . The system of  claim 1 , wherein the RF stimulation therapy alters or interrupts transmission of action potentials by one or more nerves at the target area. 
     
     
         7 . The system of  claim 6 , wherein the therapeutic output signal comprises a pulse train having a pulse frequency between 1 Hz and 10 KHz, a pulse amplitude between 0.3 mA and 20 mA, a pulse width of between 5 μsec and 250 μsec. 
     
     
         8 . The system of  claim 7 , wherein a duration of the therapeutic output signal is in a range of 20-30 minutes. 
     
     
         9 . The system of  claim 1 , wherein the RF ablation therapy induces necrosis in cells at the target area. 
     
     
         10 . The system of  claim 9 , wherein the therapy output comprises a pulse train, having a duty cycle) up to 50%, a pulse amplitude between 45V and 60V, and a pulse width of 0.050 μsec. 
     
     
         11 . The system of  claim 10 , wherein a duration of the therapeutic output signal is in a range of 140-220 seconds. 
     
     
         12 . The system of  claim 1 , wherein the therapeutic output signal is further configurable to increase a temperature at the target area to provide analgesic heat therapy. 
     
     
         13 . The system of  claim 12 , wherein, the therapeutic output signal comprises a pulse train has a duty cycle between 50 and 95%, a single electrode pulse amplitude between 1 mA and 50 mA, a pulse train duration of between continuous and 50% of time. 
     
     
         14 . The system of  claim 13 , wherein the duration of the therapeutic output signal is in a range of 20-30 minutes. 
     
     
         15 . The system of  claim 1 , wherein the therapeutic output signal is configurable in response to a control signal that selects the therapeutic output signal to be one of RF stimulation therapy and RF ablation therapy. 
     
     
         16 . The system of  claim 1 , wherein the target area of nerves comprises a dorsal root ganglion (DRG). 
     
     
         17 . An implantable medical device configured for chronic implant with an orthopedic implant device having a hardware component, the device comprising:
 one or more electrodes configured to be implanted in, on, or adjacent a target area of nerves;   an RF energy interface configured to receive energy from an external RF energy interface over a wireless energy link;   an energy storage component coupled to the RF energy interface through charging circuitry and configured to store the energy; and   a RF therapy controller coupled to the energy storage component and the one or more electrodes, the RF therapy controller configured to: 1) generate a therapeutic output signal from the stored energy, the therapeutic output signal comprising pulses of an RF signal oscillating at a frequency in a therapy band in a range of 300-500 KHz, and 2) deliver the therapeutic output signal to one or more of the plurality of electrodes.   a housing configured to enclose the RF therapy controller and the energy storage component, and to be mechanically coupled to the hardware component of the orthopedic implant device.   
     
     
         18 . The device of  claim 17 , wherein the RF therapy controller is configured to generate anyone of a plurality of different therapeutic output signals comprising a RF stimulation output, a RF heat output, and a RF ablation output. 
     
     
         19 . The device of  claim 18 , wherein the RF stimulation output comprises a pulse train having a pulse frequency between 1 Hz and 10 KHz, a pulse amplitude between 0.3 mA and 20 mA, a pulse width of between 5 μsec and 250 μsec. 
     
     
         20 . The device of  claim 18 , wherein, the RF heat output comprises a pulse train has a duty cycle between 50 and 95%, a single electrode pulse amplitude between 1 mA and 50 mA, a pulse train duration of between continuous and 50% of time. 
     
     
         21 . The device of  claim 18 , wherein the RF ablation output comprises a pulse train, having a duty cycle up to 50%, a pulse amplitude between 45V and 60V, and a pulse width of 0.050 μsec.