Michael Foerster

WIMAGINE: Wireless 64-Channel ECoG Recording Implant for Long Term Clinical Applications

A wireless 64-channel ElectroCorticoGram (ECoG) recording implant named WIMAGINE has been designed for various clinical applications. The device is aimed at interfacing a cortical electrode array to an external computer for neural recording and control applications. This active implantable medical device is able to record neural activity on 64 electrodes with selectable gain and sampling frequency, with less than 1 μV RMS input referred noise in the [0.5 Hz - 300 Hz] band. It is powered remotely through an inductive link at 13.56 MHz which provides up to 100 mW. The digitized data is transmitted wirelessly to a custom designed base station connected to a PC. The hermetic housing and the antennae have been designed and optimized to ease the surgery. The design of this implant takes into account all the requirements of a clinical trial, in particular safety, reliability, and compliance with the regulations applicable to class III AIMD. The main features of this WIMAGINE implantable device and its architecture are presented, as well as its functional performances and long-term biocompatibility results.

A wireless multichannel EEG recording platform

A wireless multichannel data acquisition system is being designed for ElectroEncephaloGraphy (EEG) recording. The system is based on a custom integrated circuit (ASIC) for signal conditioning, amplification and digitization and also on commercial components for RF transmission. It supports the RF transmission of a 32-channel EEG recording sampled at 1 kHz with a 12-bit resolution. The RF communication uses the MICS band (Medical Implant Communication Service) at 402–405 Mhz. This integration is a first step towards a lightweight EEG cap for Brain Computer Interface (BCI) studies. Here, we present the platform architecture and its submodules. In vivo validations are presented with noise characterization and wireless data transfer measurements.

A wireless 64-channel ECoG recording Electronic for implantable monitoring and BCI applications: WIMAGINE

A wireless, low power, 64-channel data acquisition system named WIMAGINE has been designed for ElectroCorticoGram (ECoG) recording. This system is based on a custom integrated circuit (ASIC) for amplification and digitization on 64 channels. It allows the RF transmission (in the MICS band) of 32 ECoG recording channels (among 64 channels available) sampled at 1 kHz per channel with a 12-bit resolution. The device is powered wirelessly through an inductive link at 13.56 MHz able to provide 100mW (30mA at 3.3V). This integration is a first step towards an implantable device for brain activity monitoring and Brain-Computer Interface (BCI) applications. The main features of the WIMAGINE platform and its architecture will be presented, as well as its performances and in vivo studies.

WIMAGINE ® : 64-channel ECoG recording implant for human applications

A wireless 64-channel ElectroCorticoGram (ECoG) recording implant named WIMAGINE® has been designed for clinical applications. This active implantable medical device is able to record ECoG on 64 electrodes with selectable gain and sampling frequency, with less than 0.7μVRMS input referred noise in the [0.5Hz - 300Hz] band. It is powered remotely through an inductive link at 13.56MHz, communicates wirelessly on the MICS band at 402-405MHz with a custom designed base station connected to a PC and complies with the regulations applicable to class III AIMD. The design of the housing and the antenna have been optimized to ease the surgery and to take into account all the requirements of a clinical trial in particular patient safety and comfort. The main features of this WIMAGINE® implantable device and its architecture will be presented, as well as its performances and in vivo validations.

KDI: A wireless ECoG recording platform with impedance spectroscopy, electrical stimulation and real-time, lossless data compression.

A power-efficient modular wireless platform has been designed for prototyping and pre-clinical evaluations of neural recording implants. This Kit for Designing Implants (KDI) is separated in function specific modules of 34×34mm which can be assembled as needed. This paper presents the design of new modules for this existing wireless KDI platform. These modules cover the functionalities of electrical stimulation for BCI neurofeedback, impedance spectroscopy for monitoring tissue reaction around implanted electrodes and a real-time lossless data compression algorithm for ECoG signals. This algorithm has been implemented using two different hardware solutions and its performances compared. The design and evaluation of these modules are a first step towards the inclusion of these functionalities into the next generation of WIMAGINE® implants.

KDI: A wireless power-efficient modular platform for pre-clinical evaluation of implantable neural recording designs

This paper presents a power-efficient modular wireless platform which has been designed for prototyping and pre-clinical evaluations of neural recording implants. This Kit for Designing Implants (KDI) is separated in function specific modules of 34×34mm which can be assembled as needed. Five modules have been designed and optimized for ultra-low power consumption and a protective casing has been designed for pre-clinical trials. Two different wireless modules have been compared and the KDI performances have been evaluated in terms of modularity, wireless throughput and power consumption.