An implantable wireless multi-channel neural prosthesis for epidural stimulation

Abstract

This paper presents a fully implantable multi-channel neural prosthesis for epidural stimulation. The prosthesis features three telemetry-operated independent stimulators providing in total eighteen stimulation channels. The stimulator circuits were implemented in a 0.6-µm CMOS technology. The prosthesis is protected in a hermetically sealed ceramic enclosure and encapsulated in medical grade silicone rubber. In-vitro measured results with electrodes in saline are presented.

A Sensory Feedback Neural Stimulator Prototype for Both Implantable and Wearable Applications

“…The other stimulation parameter ranges are 100-600 Hz for the pulse frequency and 100-500 µs for the pulse width. Comparing the proposed IPG with the literature (Table 2), we propose a system equipped with a greater number of channels, 12 more than those reported in [25] and an order of magnitude greater than other works found in the literature [26,27,29]. Furthermore, the stimulus's maximum PA is 1 mA greater than [27], 2 mA greater than [25], 3 mA greater than [29], and nearly 4 mA greater than [26].…”

“…One of the biggest challenges in the field of sensory feedback via PNS concerns the design of the implantable system; in fact, this must have low energy consumption, have reliable and stable long-term operation, and, obviously, respect the biocompatibility characteristics, have small dimensions and must be able to communicate with the outside. The stimulation waveform used in this study was the symmetric biphasic square wave, as used in the literature both for PNS [12,[25][26][27][28][29] and for TENS [30][31][32][33][34][35] since it was shown to be able to elicit a more comfortable sensation among the other stimulation waveforms. The biphasic square wave settable parameters are the pulse amplitude (PA), the pulse width (PW), the pulse frequency (PF), and stimulation duration (i.e., the number of pulses).…”

“…Another solution presents an implantable nerve stimulator, used for different purposes: in [25], an implantable wireless multi-channel neural prosthesis for epidural stimulation was presented. The implantable board (46 mm × 42.8 mm × 8.8 mm) presents a receiving coil for the supply through wireless power transfer, and three stimulating systems, each providing six active channels and two return electrodes.…”

A Versatile Hermetically Sealed Microelectronic Implant for Peripheral Nerve Stimulation Applications

“…Furthermore, the external current booster using THAT380 was external to the stimulator ASICs, and could be eliminated with a new stimulator ASIC design. 3) Communication Latency: In the first version transmitter design (Jiang et al, 2016), an easyRadio ISM module eRA900TRS was used for the communication with the remote host, chosen for its low power consumption, but it was found that the inter packet delay is not optimal. A BLE radio link is chosen for the second version transmitter design.…”

“…A reflux condenser was installed on the flask to keep the volume of the deionized water unchanged. The implant was inductively powered by the first version of the wearable transmitter (Jiang et al, 2016) continuously during the entire course of the accelerated lifetime test. Data packets from the implant were frequently checked to monitor the status of the implant electronics and to ensure the wireless power transfer at a level sufficient for operation.…”