Patent ID: 8818515
Filing Date: 2014-08-26
Classification: A61N

Abstract:
1. A method of delivering neurostimulation to a patient, the method comprising: setting a desired target value for electrical current and a target time duration for delivery of the target value of electrical current to the patient, said current target value and said target time duration defining a therapeutic neurostimulation potential delivered to the patient; measuring electrical resistance between a first electrode and a second electrode coupled to the patient; setting a first predetermined voltage limit to be applied across the first and second electrodes based at least in part on the measured electrical resistance, the first predetermined voltage limit having a voltage value different than the voltage required to reach the desired current target value based on the measured resistance; initiating a flow of electrical current through the first electrode and the second electrode coupled to the patient; increasing a voltage across the first and second electrodes to thereby control the rate of increase in the flow of electrical current toward the target value during a current-controlled ramp-up period; preventing the voltage across the first and second electrodes from increasing beyond the first predetermined limit prior to reaching the target current value during the ramp-up period; and controlling the voltage within the predetermined range during a voltage-controlled control mode for a period of time, wherein the amplitude of the electrical current continues to increase toward the target value during at least part of the time when the voltage across the first electrode and the second electrode is maintained at or near the voltage limit for a period of time, wherein the target time for duration of delivery of the target current is significantly greater than the period of time that the voltage is controlled within the predetermined range such that the therapeutic neurostimulation potential is not changed even as a maximum voltage is potentially decreased, and wherein the first predetermined voltage limit is selected in a range such that the target current value is reached.