New nano-implant could one day help restore sight

A team of engineers at the University of California San Diego and La Jolla-based startup Nanovision Biosciences Inc. have developed the nanotechnology and wireless electronics for a new type of retinal prosthesis that brings research a step closer to restoring the ability of neurons in the retina to respond to light. The researchers demonstrated this response to light in a rat retina interfacing with a prototype of the device in vitro. 

The technology could help tens of millions of people worldwide suffering from neurodegenerative diseases that affect eyesight, including macular degeneration, retinitis pigmentosa and loss of vision due to diabetes.

The new prosthesis relies on two groundbreaking technologies. One consists of arrays of silicon nanowires that simultaneously sense light and electrically stimulate the retina accordingly. The nanowires give the prosthesis higher resolution than anything achieved by other devices—closer to the dense spacing of photoreceptors in the human retina. The other breakthrough is a wireless device that can transmit power and data to the nanowires over the same wireless link at record speed and energy efficiency.

For proof-of-concept, the researchers inserted the wirelessly powered nanowire array beneath a transgenic rat retina with rhodopsin P23H knock-in retinal degeneration. The degenerated retina interfaced in vitro with a microelectrode array for recording extracellular neural action potentials (electrical "spikes" from neural activity). Animal tests with the device are in progress, with clinical trials following.