Developing a wireless intracranial neuromonitoring device for drug-resistant epilepsy

Research question Can an implantable microchip replace the current benchtop equipment used for epilepsy pre-surgical intracranial stereo-electroencephalography - enabling home monitoring that reduces patient distress, and increases the quantity and quality of data gathered? Background Epilepsy is a severe, noncommunicable neurological condition causing recurrent seizures.

Resective brain surgery is the one major curative treatment option for the approximately 30% of affected patients who cannot control their seizures with medicine.

Safety, risk and efficacy concerns remain key barriers to more widespread adaptation of surgical treatment, which frequently require s a period of pre-operative intracranial electroencephalography monitoring to localise the site of seizure onset.

The monitoring duration is typically 8-10 days and is upper bounded by high clinical costs, clinical capacity, patient distress and the risk of complications associated with an open wound and tethered electrodes.

Not all patients experience a seizure during the short monitoring period and more than 1/3 of the patients are deemed unsuitable for surgery due to unsuccessful determination of a suitable target for resection.

Outcomes from surgery are generally good, but a substantial number of patients continue to experience seizures – in part attributed to inadequately targeted resection.

Aims and Objectives Overall Aim: To refine and validate a prototype medical device for intracranial epilepsy stereo-electroencephalography. Specific Objectives: 1. To modify a wireless instrumentation microchip to be suitable for first-in-human studies; 2.

To facilitate a series of first-in-human studies to gather safety data and establish efficacy data compared to current benchtop solutions; 3.

To implement a regulatory infrastructure including a quality management system and complete a technical file for MHRA and ethics approvals; 4. To establish and streamline the clinical workflow and assess the cost-effectiveness for the NHS.

Methods A next generation full-custom wireless microchip system integrating our neural recording front-end designs with our wireless power transmission and data communication technology will be designed for low frequency, high channel count EEG requirements, with enhanced safety profile to align with best practice and regulatory requirements for in-human operation.

Recording capability will be evaluated in benchtop testing to provide safety, ethics, and efficacy data to support first-in-human trials.

Performance, reliability and stability of the wireless link will be quantified in benchtop testing and validated in cadaver testing .

The device s usability and performance will be evaluated in a clinical study involving intracranial electroencephalography in 5 epileptic patients undergoing presurgical assessment.

Anticipated Impact The ultimate medical device will consist of intracranial electrodes connected to an implant which wirelessly transmits the electroencephalography signals through the skin to a wearable readout device.

Following implantation the patient s skin can be fully closed, greatly reducing infection risks and enabling the patient to return home for extended monitoring.

A longer monitoring period with patients free to continue their life as normal should mean: much less patient distress, more seizures captured, better localisation data, reduced clinical costs and ultimately better surgical outcomes (with substantial associated long term cost savings).