34 results about "Evoked compound action potential" patented technology

A system of non-linear feedback control for spinal cord stimulation is provided. The system comprises a lead adapted to be implanted within an epidural space of a dorsal column of a patients spine, and a pulse generator (PG) electrically coupled to the lead. The PG is configured to deliver spinal cord stimulation (SCS) therapy. The system also comprises a sensing circuitry configured to sense an evoked compound action potential (ECAP) response that propagates along the neural pathway. The system also comprises a processor programmed to operation, in response to instructions stored on a non-transient computer-readable medium, to obtain a baseline ECAP response when the lead and spinal cord tissue properties are in baseline states; analyze ECAP responses relative to the baseline ECAP response to obtain an ECAP feedback difference indicative of a change in at least one of the baseline state of the lead and the baseline state of the spinal cord tissue properties. The processor is also programmed to adjust an SCS therapy based on the ECAP feedback.

The accuracy of neural response recordings in neural stimulators, e.g., cochlear implants, is often degraded by a recording artifact. An idealized electrical-equivalent model of a neural stimulator is created to study, measure and compensate for artifact evoked compound action potential (eCAP). Using this model, the artifact is shown to occur even when the electrical components that make-up the neural stimulator are ideal. The model contains parasitic capacitances between the electrode wires. The model demonstrates that these small parasitic capacitances provide a current path during stimulation which can deposit charge on the electrode-tissue interfaces of the recording electrodes. The dissipation of this residual charge and the charge stored across the stimulating electrode is seen as the recording artifact. The proposed solution for eliminating the artifact problem is realized by utilizing a capacitive electrode material, e.g., TiO2, Ta2O5, or other dielectric coatings or films, instead of Faradaic electrode material, e.g., Platinum (Pt), Pt—Ir alloy or similar alloys, on the neural stimulator electrode lead.

A method of surgically positioning an electrode array at a desired implantation location relative to a nerve. A temporary probe electrode is temporarily positioned adjacent to the nerve and at a location which is caudorostrally separate to the desired implantation location of the electrode array. The implanted position of the probe electrode is temporarily fixed relative to the nerve. During implantation of the electrode array, electrical stimuli are applied from one of the temporarily fixed probe electrode and the electrode array, to evoke compound action potentials on the nerve. Compound action potentials evoked by the stimuli are sensed from at least one electrode of the other of the temporarily fixed probe electrode and the electrode array. From the sensed compound action potentials a position of the electrode array relative to the nerve is determined.

Estimating a nerve-to-electrode distance involves applying a stimulus from a stimulus electrode to a nerve. Neural measurements of at least one evoked compound action potential are obtained, and processed in order to estimate an originating state of stimulation exhibiting at least one characteristic defined by a single fibre size. A single fibre model is then applied to produce a measure of the nerve-to-electrode distance. Also provided for is estimation of a distribution of recruited fibres. Measurements of a compound action potential are obtained from sense electrodes spaced apart along a neural pathway. A conduction velocity of the compound action potential is determined from the latency between the measurements. From the conduction velocity a dominant recruited fibre diameter is determined. A rate of dispersion of the compound action potential between the sense electrodes is determined. From the rate of dispersion a distribution of diameters of the recruited fibre population is determined.

Estimating a nerve-to-electrode distance involves applying a stimulus from a stimulus electrode to a nerve. Neural measurements of at least one evoked compound action potential are obtained, and processed in order to estimate an originating state of stimulation exhibiting at least one characteristic defined by a single fibre size. A single fibre model is then applied to produce a measure of the nerve-to-electrode distance. Also provided for is estimation of a distribution of recruited fibres. Measurements of a compound action potential are obtained from sense electrodes spaced apart along a neural pathway. A conduction velocity of the compound action potential is determined from the latency between the measurements. From the conduction velocity a dominant recruited fibre diameter is determined. A rate of dispersion of the compound action potential between the sense electrodes is determined. From the rate of dispersion a distribution of diameters of the recruited fibre population is determined.

The automatic measurement of evoked compound action potential (ECAP) thresholds of the auditory nerve; that is, a neural response, concurrently with the performance of psychophysics measurements of a prosthetic hearing implant recipient. During the fitting process, a stimulus signal comprising two components is applied to each stimulation channel. One signal component is configured to elicit an ECAP neural response, referred to herein as a neural response signal component. The other component is configured to elicit a response to a psychophysics stimulation, referred to herein as a psychophysics signal component. Indications of the psychophysics measurement and the concurrently obtained neural response measurements are provided to the user. For the psychophysics measurement, this includes the selected characteristics of the psychophysics signal component since the results of the applied stimulation is a recipient behavioral or auditory response.

A system and method for modeling patient-specific spinal cord stimulation (SCS) is disclosed. The system and method acquire impedance and evoked compound action potential (ECAP) signals from a lead positioned proximate to a spinal cord (SC). The lead includes at least one electrode. The system and method determine a patient-specific anatomical model based on the impedance and ECAP signals, and transform a dorsal column (DC) map template based on a DC boundary of the patient-specific anatomical model. Further, the system and method map the transformed DC map template to the patient-specific anatomical model. The system and method may also include the algorithms to solve extracellular and intracellular domain electrical fields and propagation along neurons. The system and method may also include the user interfaces to collect patient responses and compare with the patient-specific anatomical model as well as using the patient-specific anatomical model for guiding SCS programming.

A method of fitting to a recipient a cochlear implant including a plurality of stimulation channels. The method comprises applying to at least one stimulation channel of the cochlear implant a first stimulus signal comprising a neural response component and a psychophysics signal component, automatically measuring a strength of an evoked compound action potential (ECAP) of the recipient evoked in response to the application of the neural response component of the first stimulus signal, and simultaneously providing to a user an indication of the automatically measured strength of the ECAP and a value of the applied psychophysics signal component.

A system and method for treating a patient suffering from chronic hypertension. Electrical therapeutic energy is delivered to a nerve branch of a renal artery of the patient, thereby treating the chronic hypertension. Another system and method for treating a medical condition of a patient. Electrical stimulation energy is delivered to a stimulation site on the wall of a blood vessel, thereby evoking a compound action potential in a nerve branch associated with the blood vessel, sensing the evoked compound action potential at a sensing site on the wall of the blood vessel, identifying a circumferential location of the nerve branch as being adjacent the stimulation site or sensing site based on the sensed compound action potential(s), and delivering therapeutic energy to a therapeutic site on the wall of the blood vessel adjacent the circumferential location of the nerve branch, thereby modulating the nerve branch and treating the medical condition.

A method for analyzing nerve fibers distribution is provided, including inputting a stimulation signal into a nerve tissue through at least two sensing and conducting electrodes, applying a stimulation signal ratio to control the stimulation signal using an electric current steering technique to electrically stimulate a plurality of nerve fibers within a plurality of stimulations areas of the nerve tissue; receiving a plurality of evoked compound action potentials (ECAP) using at least two sensing and conducting electrodes due to the nerve fibers electrically stimulated and computing a distance between the nerve fiber and the conducting electrodes including eliminating non-ideal effect caused by an electric potential attenuation factor, wherein the electric potential attenuation factor is a function of the distance between each of the conducting electrodes and the nerve tissue; and integrating and comparing the received ECAPs and analyzing the nerve fibers distribution of the nerve tissue.