Long-Term Functionality of Transversal Intraneural Electrodes Is Improved By Dexamethasone Treatment

Area of Science:

• Biomedical Engineering
• Neuroscience
• Regenerative Medicine

Background:

• Neuroprostheses use neural interfaces for limb function restoration.
• Intraneural electrodes in peripheral nerves are key for prosthetic control and sensory feedback.
• Foreign body reaction (FBR) causes tissue encapsulation, degrading electrode performance over time.

Purpose of the Study:

• To evaluate the effect of dexamethasone on FBR and neural electrode performance.
• To assess stimulation and recording capabilities of intraneural electrodes with chronic dexamethasone administration.

Main Methods:

• Transversal intraneural multi-channel electrodes (TIMEs) were implanted in rat sciatic nerves.
• Animals received chronic dexamethasone or saline treatment for 3 months.
• Stimulation thresholds, selectivity, and signal-to-noise ratio were evaluated.

Main Results:

• Dexamethasone significantly reduced stimulation thresholds compared to saline.
• Electrode selectivity remained unaffected by dexamethasone treatment.
• Dexamethasone maintained more active electrode sites over time.
• No improvement in signal-to-noise ratio was observed with dexamethasone.

Conclusions:

• Systemic dexamethasone administration is a viable strategy to mitigate FBR around chronically implanted neural electrodes.
• Dexamethasone enhances the longevity and efficacy of neuroprosthetic interfaces by preserving electrode functionality.
• This approach holds promise for improving outcomes in patients with limb loss requiring neuroprosthetic devices.