Neuromodulation Lead Offset Measurement for Therapy Programming
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Neuromodulation systems face challenges in accurately detecting neural responses due to electrode artefacts, maintaining appropriate neural recruitment, and managing power consumption, especially with multiple electrode leads that can migrate, affecting therapy efficacy and patient comfort.
Innovation Solution
An implantable device and method for determining the relative positional offset between two electrode leads by processing stimulus artefacts and evoked compound action potentials, using a processor to measure and adjust stimulus configurations to maximize artefacts for lead offset measurement, and employing analytical models to refine lead positioning.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multiple electrode leads are implanted to improve therapy coverage, then therapeutic effectiveness is improved, but lead migration risk increases affecting positioning accuracy
Solution Approach 1:
The system performs preliminary measurement of stimulus artefacts to determine lead offset before final therapy programming. By measuring artefact characteristics during implantation, the system establishes baseline positioning data that guides subsequent therapeutic configuration, ensuring optimal lead placement before therapy begins
Solution Approach 2:
The system continuously monitors stimulus artefact signals and uses this feedback to detect lead migration. When artefact characteristics change indicating lead displacement, the system can alert clinicians and adjust therapy parameters to maintain effective treatment despite positioning changes
2Measurement precision
If stimulus intensity is increased to overcome artefact interference, then neural response detection capability is improved, but power consumption increases
Solution Approach 1:
The system extracts and measures stimulus artefact characteristics separately from the neural response signal. By isolating the artefact component through dedicated measurement circuits and signal processing, the system can characterize lead positioning without requiring high stimulus intensities that would increase power consumption
Solution Approach 2:
The system replaces direct neural response measurement with stimulus artefact measurement for lead offset determination. Instead of relying on weak neural signals that require high-gain amplification and high stimulus intensity, the system uses the stronger, more easily measurable stimulus artefact to infer lead positioning, thereby reducing power consumption
3Measurement precision
If lead offset measurement is performed to improve therapy programming, then treatment accuracy is improved, but device complexity increases
Solution Approach 1:
The system performs lead offset measurement automatically using its own stimulus and measurement circuits without requiring external equipment. The implantable device generates stimulus signals, measures the resulting artefacts, and calculates lead offset internally, making the device self-sufficient for positioning characterization
Solution Approach 2:
The system varies stimulus parameters such as pulse amplitude, width, and frequency to optimize artefact measurement for lead offset determination. By adjusting these parameters, the system enhances the signal-to-noise ratio of artefact measurements and improves measurement accuracy while maintaining simple device operation
Data Source
AI summary
Disclosed is an implantable device for lead offset determination, comprising first and second electrode leads. A stimulus is delivered from one lead to tissue, and a signal is sensed from the tissue by the other lead. The sensed signal is processed to produce a measure of a stimulus artefact present in the signal. The stimulus artefact measure is used to produce a measure of an offset between the first electrode lead and the second electrode lead, such as by applying a distance-squared analytical model to measures of stimulus artefact obtained from at least two sense electrodes. And/or, a compound action potential evoked by the stimulus is sensed from neural tissue, a latency of the evoked compound action potential is measured, and a measure of an offset between the first electrode lead and the second electrode lead is produced from the latency.