Holographic Bionic Vision Uses Gene Therapy
Biomedical engineers in Israel are testing the power of holography to artificially stimulate cells in the eye, with hopes of developing a new strategy for bionic vision restoration.
Computer-generated holography, the researchers say, could be used in conjunction with a technique called optogenetics, which uses gene therapy to deliver light-sensitive proteins to damaged retinal nerve cells. In conditions such as Retinitis Pigmentosa (RP) these light-sensing cells degenerate and lead to blindness.
Professor Shy Shoham of the Technion-Israel Institute of Technology said the idea behind optogenetics is to take a light-sensitive protein from another organism, typically from algae or bacteria, and insert it into a target cell, and that photosensitizes the cell.
Intense pulses of light can activate nerve cells newly sensitised by this gene therapy approach. But Professor Shoham said researchers around the world are still searching for the best way to deliver the light patterns so that the retina “sees” or responds in a nearly normal way.
The researchers have tested the potential of holographic stimulation in retinal cells in the lab
The plan is to someday develop a prosthetic headset or eyepiece that a person could wear to translate visual scenes into patterns of light that stimulate the genetically altered cells.
In a paper published in Nature Communications, the researchers showed that light from computer-generated holography could be used to stimulate these repaired cells in mouse retinas.
The key, they say, is to use a light stimulus – such as holography – that is intense, precise, and can trigger activity across a variety of cells all at once.
The researchers have tested the potential of holographic stimulation in retinal cells in the lab, and have done some preliminary work with the technology in living mice with damaged retinal cells. The experiments show that holography can provide reliable and simultaneous stimulation of multiple cells
at millisecond speeds.
But implementing a holographic prosthesis in humans is far in the future, Professor Shoham cautioned.