Alfred Mann Foundation

Feasibility of Prosthetic Posture Sensing Via Injectable Electronic Modules

BION electronic subassembly redesigned for sensors. Multiple microsensors have been developed for posture sensing while keeping the device injectable.

Current design of BION implants for stimulation only, including hermetic glass capsule and electrodes.

NEUROTECHNOLOGY FUNDAMENTALS & EMERGING DEVICES FOR THE TREATMENT OF PARALYSIS

Alfred Mann Foundation microstimulator family

Hitting the Right NERVE

AMF's RF microstimulators are implanted into a patient's arm and act as “bionic neurons” mimicking messages from the brain to recreate useful function in paralyzed or weak arms. The cylindrical Bion microstimulators measure 1.7 cm long and 2.4 mm in diameter. Surgeons inject them into the body through small minimally invasive incisions, reducing the expense and risks of traditional complex surgical procedures. They are implanted next to a nerve or on a muscle at the motor point close to where it's attached to a nerve. Once implanted, the microstimulators receive power and stimulation commands over an RF coil (fitted to the arm) that is connected to a control unit. “The control unit generates signals and delivers them to the coil, and the coil delivers magnetic energy to the Bion,” says Jay Yonemoto, Applications Development Manager, Alfred Mann Foundation. “The coils power the Bion up and let us deliver commands. They control pulse width, amplitude, and rate. The control unit can have up to three different programs which let investigators program three different therapeutic routines such as strength training for different muscle groups.” Functional electrical stimulation (FES) applies low-level electrical currents to the body to restore or improve function.

A Revolution in Prosthetics

biomimetic systems are able to restore lost function to complex neural systems. We use them to restore the electrical signals that are normally sent out from the motor neurons to different parts of the body.

Loeb’s lab in the Alfred Mann Institute for Biomedical Engineering at USC has been named one of several major subcontractors in a $30.4-million contract for the Defense Advanced Research Projects Agency (DARPA). To build a sophisticated control system that will replace parts of the nervous system and allow the user to operate the artificial limb neurally, just by thinking about it.

AMF Research

The Implantable Microstimulator

A magnetically controlled and powered injectable neuromuscular stimulation device for impaired neural and muscular functions. Forty-five devices were implanted in subject with the intent to restoring function to paralyzed upper limbs. Between 5 and 7 microstimulators were implanted on the nerve or motor point of the affected muscles in each of seven patients to exercise the limb.

New Product Development, the Injectable Microstimulator System

R&D team at THE FOUNDATION is developing a system of battery powered injectable microstimulators and microsensors, each of which can be controlled and monitored up to 100 times a second via radio communication.

The BION

The BION® system is a wireless network of up to 255 single-channel stimulators controlled and powered by an RF link from a central external controller. Each stimulator consists of a ceramic and titanium cylinder capped at each end with anode and cathode, both platinum. The cylinder is 15.6 mm long and 2.5 mm in diameter. Each stimulator produces asymmetric biphasic capacitively-coupled constantcurrent pulses. Pulse width (0 to 500 µsec), pulse amplitude (0 to 40 mA) and pulse frequency (0 to 3,472 pps shared among all active BION® stimulators) are controlled digitally by the external controller via a 2 MHz AC magnetic link. [1-6]

Neural Engineering's Image Problem By James Cavuoto

A study by publisher Neurotech Reports, San Francisco, projects that the market for implanted systems will reach $3.6 billion by 2008 and it is now growing at an annual rate of 36 percent

A Revolution in Prosthetics

The Department of Defense is keen to develop this rehabilitative technology for soldiers who have lost their arms or legs in combat. Consequently, Loeb’s lab in the Alfred Mann Institute for Biomedical Engineering at USC has been named one of several major subcontractors in a $30.4-million contract for the Defense Advanced Research Projects Agency (DARPA)

R a n d a l l M o r t o n BBus BComp BPsych