Battery‐Powered Implantable Nerve Stimulator for Chronic Activation of Two Skeletal Muscles Using Multichannel Techniques

Abstract

Chronic activation of skeletal muscle is used clinically in representative numbers for diaphragm pacing to restore breathing and for dynamic graciloplasty to achieve fecal continence. The 3 different stimulation techniques currently used for electrophrenic respiration (EPR) all apply high frequency powered implants. It was our goal to make these stimulation methods applicable for EPR by a battery-powered nerve stimulator that would maximize the patient's freedom of movement. Additionally, the system should allow the implementation of multichannel techniques and alternating stimulation of 2 skeletal muscles as a further improvement in graciloplasty. Generally, the developed implantable nerve stimulator can be used for simultaneous and alternating activation of 2 skeletal muscles. Stimulation of the motor nerve is achieved by either single channel or multichannel methods. Carousel stimulation and sequential stimulation can be used for graciloplasty as well as for EPR. For EPR we calculated an operating time of the implant battery of 4.1 years based on the clinically used stimulation parameters with carousel stimulation. The multichannel pulse generator is hermetically sealed in a titanium case sized 65 x 17 mm (diameter x height) and weighs 88 g.

An implantable bi-directional wireless transmission system for transcutaneous biological signal recording

“…The current implantable device uses a two-coil strategy to protect the weak biological signals from the effects of the strong RF electromagnetic fields generated by the inductive coupling. The impedance reflection technique, utilizing a LSK modulation method, is generally adopted in implantable biomicrosystem applications (Smith et al 1998, Gudnason et al 2001, Lanmüller et al 1999. This study adopts the LSK unit, shown in figure 5, which is modified from the unit described previously by Tang et al (1995).…”

Micropyramid structured photo capacitive interfaces

“…Wireless neuromodulation has been a widely researched topic [1][2][3][4] resulting in different practical approaches such as battery-powered [5,6] and remotely operated [7,8] devices, as well as remotely powered and controlled devices. Implants can be remotely powered by ultrasound [7,9], magnetic induction [2,10], radiofrequency electromagnetic waves [11][12][13], as well as driven by light [14][15][16][17].…”

“…All of the aforementioned methods have the advantage for in vivo experimental and therapeutic usage in comparison to wired devices. However, most of them are attached to a set of limitations and disadvantages, such as a large form factor [24], limited tissue penetration [25] and the need for complex external apparatus for powering and controlling the implants [26]. Implants offering effective and stable operation, minimally invasive form-factor and simple remote power and control would have a distinct advantage over the competing technologies.…”

Pre-Filtering of Stimuli for Improved Energy Efficiency in Electrical Neural Stimulation

“…However, there are safety and practical constraints on the energy that can be transferred to and/or stored on such devices [1]. As most of this energy is used by the stimulator circuitry, its power efficiency can play a role in prolonging the functional lifetime of a stimulator device (e.g., battery-powered implants [2]), improving the quality of prosthetic function (e.g., more stimulation sites in visual prostheses [3]), or miniaturizing wireless implants (e.g., smaller receiving aperture in mm-sized implants [4], [5]).…”