Abstract: Monitoring circuitry for an implantable stimulator device is disclosed. A switching matrix allows current from a current source to be distributed to any of a plurality of electrodes. A voltage drop across the active switches in the switch matrix is monitored and is compared to an expected voltage based upon the amplitude of the current and the known on resistance of the switch. If the monitored and expected voltages differ significantly, then a failure condition can be inferred, and an appropriate action can be taken, such shutting down stimulation. Using the already-existing switches in the switching matrix in this fashion is beneficial because it allows the current through the electrodes to be monitored without providing additional structures in the therapeutic current path, which would increase complexity and add unwanted resistance.

Abstract: Monitoring circuitry for an implantable stimulator device is disclosed. A switching matrix allows current from a current source to be distributed to any of a plurality of electrodes. A voltage drop across the active switches in the switch matrix is monitored and is compared to an expected voltage based upon the amplitude of the current and the known on resistance of the switch. If the monitored and expected voltages differ significantly, then a failure condition can be inferred, and an appropriate action can be taken, such shutting down stimulation. Using the already-existing switches in the switching matrix in this fashion is beneficial because it allows the current through the electrodes to be monitored without providing additional structures in the therapeutic current path, which would increase complexity and add unwanted resistance.

Abstract: Monitoring circuitry for an implantable stimulator device is disclosed. A switching matrix allows current from a current source to be distributed to any of a plurality of electrodes. A voltage drop across the active switches in the switch matrix is monitored and is compared to an expected voltage based upon the amplitude of the current and the known on resistance of the switch. If the monitored and expected voltages differ significantly, then a failure condition can be inferred, and an appropriate action can be taken, such shutting down stimulation. Using the already-existing switches in the switching matrix in this fashion is beneficial because it allows the current through the electrodes to be monitored without providing additional structures in the therapeutic current path, which would increase complexity and add unwanted resistance.

Abstract: A method for implanting a lead within brain tissue of a patient, wherein the lead comprises a set of radially segmented electrodes on a distal end of the lead is provided. The method includes performing a plurality of microelectrode recordings through a respective plurality of recording tracts in the brain tissue; based on the microelectrode recordings, creating a three-dimensional map of a brain structure; positioning a graphical representation of the radially segmented electrodes over the map of the brain structure to create a graphical depiction of a desired depth and a desired radial orientation of the lead within the brain tissue; and implanting the lead in the brain tissue in accordance with the desired depth and desired radial orientation. A device for determining a radial orientation of the lead includes a radially directional ruler and an indicator for indicating which electrode is in contact with the ruler.