Connection quality assessment for EEG electrode arrays

Inventors

Grant, Alexander M. • Yi, Jianchun • Bachelder, Bradley G. • Woo, Raymond • Parvizi, Josef • Chao, Xingjuan

Assignees

Ceribell Inc

Abstract

Systems, devices, and methods are provided to assess connection quality between the electrodes of a bioelectrical signal measurement and/or electrical stimulation device and the tissue, typically skin, of the subject. A test signal is provided to a first electrode, voltage differences between the first electrode and additional electrodes are determined, an impedance of the first electrode is determined based on the voltages differences, and the determined impedance indicates connection quality. This process is typically repeated for all of the electrodes to determine connection quality. The user or subject can be alerted if the connection quality is poor, and the bioelectrical signal that is recorded can be provided with data points indicating connection quality during the signal recording.

Core Innovation

The invention provides a method of assessing quality of a connection between an electrical sensor or stimulator and tissue of a subject. The method includes providing an electrical sensor or stimulator comprising a plurality of electrodes and contacting the plurality of electrodes to tissue. A test signal is provided to the tissue through a first electrode of the plurality of electrodes, and a processor determines a voltage difference between the first electrode and only one other electrode in response to the test signal.

The voltage difference is determined without using either the first electrode or the only one other electrode as a common ground or a common reference electrode. Based on the determined voltage difference, a preliminary impedance of the first electrode is determined. Steps are repeated for the first electrode and other electrodes of the plurality of electrodes to generate a plurality of preliminary impedances for the first electrode.

The processor determines a final impedance of the first electrode by determining a lowest impedance of the plurality of preliminary impedances and assigning the lowest impedance as the final impedance. The connection quality of the first electrode is then determined based on the determined final impedance. The method can further derive a connection quality category based on the final impedance, and can support associating connection-quality information with recorded bioelectrical signals.

Claims Coverage

The document includes one independent claim that defines the core impedance-based connection-quality assessment, with multiple dependent claims adding constraints and optional system actions. The inventive features concentrate on differential voltage measurement against only adjacent or other electrodes without a common ground or reference, selecting the lowest preliminary impedance as the final impedance, and deriving connection quality from that final impedance.

Overall claim coverage centers on deriving electrode connection quality by applying a test signal, measuring differential voltage against only one other electrode without a common ground or reference, computing multiple preliminary impedances, selecting the lowest preliminary impedance as the final impedance, and then determining connection quality from that final impedance.

Stated Advantages

Documented Applications