Current bias as a control mechanism for electrode operation

Inventors

Ackermann, Douglas Michael • Faltys, Michael A. • Harris, James • Wu, Kenneth S.

Assignees

Presidio Medical Inc

Abstract

Disclosed herein are systems and methods for electrically modulating tissue. Systems can include a current generator; at least one implantable working electrode, the at least one implantable working electrode configured to be in electrical communication with the current generator; at least one indifferent electrode; and a controller configured to signal the current generator to: generate a set of currents with a set of initial polarities to be delivered to the working electrodes; and wherein the at least one indifferent electrode absorbs a bias current which is equal in magnitude and opposite in polarity to a summation of the set of currents.

Core Innovation

The invention provides a system for electrically modulating tissue that includes a current generator, at least one implantable working electrode in electrical communication with the current generator, at least one indifferent electrode, and a controller. The controller signals the current generator to generate a set of currents with a set of initial polarities to be delivered to the working electrodes, and the indifferent electrode absorbs a bias current that is equal in magnitude and opposite in polarity to a summation of the set of currents.

The disclosed approach uses ultra low frequency currents to provide DC and DC-equivalent stimulation in the neuromodulation context. The document emphasizes operating with high charge-capacity electrode materials and maintaining electrode voltage equilibrium within voltage windows to limit water electrolysis and corrosive or irreversible electrochemical reactions.

The disclosure contrasts with capacitor-based blocking/coupling approaches by intentionally controlling net bias current rather than using blocking capacitors. The system architecture and indifferent-electrode roles are presented with options for fixed or adjustable bias current, bias polarity, indifferent electrode types, and corresponding electrode voltage behaviors that remain within intended voltage windows during stimulation.

Claims Coverage

The document includes two independent claims that share the same core architecture: a current generator, an implantable working electrode, an indifferent electrode that absorbs an equal-magnitude opposite-polarity bias current relative to a summation of delivered working currents, and a controller that commands the delivered currents. One independent claim additionally requires ultra low frequency currents, while the other does not expressly require the ultra low frequency limitation in the independent claim text.

Across the independent claims, the main inventive coverage is the paired-current relationship in which the indifferent electrode absorbs a bias current equal in magnitude and opposite in polarity to the summation of working-electrode currents, with the controller generating the set of currents having initial polarities to be delivered to implantable working electrodes. One independent claim further limits the delivered set of currents to ultra low frequency currents.

Stated Advantages

Documented Applications