Posture-Based ECAP Growth Curve Selection for Neural Stimulation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electrical stimulation therapy systems struggle to maintain consistent neural activation and therapeutic efficacy as patients move, due to changes in the distance between electrodes and target tissues.
Innovation Solution
A medical device system that detects a patient's posture and selects an evoked compound action potential (ECAP) growth curve corresponding to that posture, using control stimulation pulses to elicit detectable ECAP signals and adjust the parameters of informed stimulation pulses to maintain consistent neural activation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If electrical stimulation therapy is delivered with fixed parameters, then the device complexity is reduced, but the therapeutic efficacy deteriorates as patients move and electrode-tissue distance changes
Solution Approach 1:
The system continuously monitors ECAP signals from control stimulation pulses and uses this feedback to automatically adjust the parameters of informed stimulation pulses. The processor compares detected ECAP characteristics to target values and modifies stimulation parameters accordingly, creating a closed-loop control system that maintains therapeutic efficacy despite patient movement.
Solution Approach 2:
The system transitions from static fixed parameters to dynamic adaptive parameters that automatically adjust in response to changing electrode-tissue distances. The stimulation parameters are continuously modified based on real-time ECAP feedback, allowing the system to adapt to patient movement and maintain optimal therapeutic effect.
2Measurement precision
If control stimulation pulses are delivered to elicit detectable ECAP signals, then the measurement precision of neural activation is improved, but the loss of time for therapy delivery increases due to interleaving with informed stimulation pulses
Solution Approach 1:
The system uses periodic control stimulation pulses interleaved with informed stimulation pulses at predetermined intervals. These periodic test pulses elicit ECAP signals that are used to adjust therapy parameters, while the majority of time is dedicated to delivering therapeutic informed stimulation pulses, minimizing the time loss from measurement activities.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The system effectively maintains consistent neural activation and therapeutic efficacy by dynamically adjusting stimulation parameters based on the patient's posture, reducing the occurrence of side effects and improving treatment outcomes.
Implementation Method 1
A medical device may deliver electrical stimulation therapy via one or more leads that include electrodes located proximate to target locations associated with the brain, the spinal cord, pelvic nerves, peripheral nerves, or the gastrointestinal tract of a patient
Implementation Method 2
An ECAP growth curve defines a relationship between a parameter defining delivery of electrical stimulation pulses delivered to the patient and a characteristic of an ECAP signal of a nerve of a patient elicited by the electrical stimulation pulses
Data Source
AI summary
Devices, systems, and techniques are described for selecting an evoked compound action potential (ECAP) growth curve based on a posture of a patient. The ECAP growth curve defines a relationship between a parameter defining delivery of stimulation pulses delivered to the patient and a parameter of an ECAP signal of a nerve of a patient elicited by a stimulation pulse. In one example, a medical device detects a posture of a patient and selects an ECAP growth curve corresponding to the detected posture. The medical device selects, based on the ECAP growth curve corresponding to the detected posture and a characteristic of a detected ECAP signal, a value for a parameter for defining delivery of the stimulation pulses to the patient and controls delivery of the stimulation pulses according to the selected value for the parameter.