Curing macular degeneration using natural and artificial vision

A new study reveals that a new treatment for age-related macular degeneration (AMD) in the older population which causes blindness in millions of people could be available soon.

Researchers from the Bar-Ilan University in Israel and Stanford University in California, US, have found evidence for the first time showing that the brain can figure out how to integrate natural and artificial vision as it maintains processing information important for seeing. This study was published in the Current Biology journal.

AMD is caused when light receptors change as people age and as the photoreceptor layer along with an adjacent supporting layer (retinal pigment epithelium) age with it too, explained Prof. Yossi Mandel, who is the head of Bar-Ilan University’s Ophthalmic Science and Engineering Lab.

These layers of light receptors are damaged when they are continuously exposed to light, heat and oxidative stress which can cause chronic damage and eventually to photoreceptor loss and blindness, says Mandel. In the Western world it is the leading cause of blindness in people 50 and over, he adds, and increases with age.

Currently there are no cures for AMD but there have been significant advancements made in artificial retina implants recently that researchers are hoping will lead to effective treatment.

Researchers explain that a device made from tiny electrodes smaller than the width of a hair can be implanted into the retina and “activating these electrodes results in electrical stimulation of the remaining retinal cells and results in visual restoration, albeit partially. AMD patients implanted with an artificial retina possess a combination of artificial central vision and normal peripheral vision.”

But whether the brain can integrate artificial and natural vision properly is the question researchers sought to answer. The study took two years in Mandel’a lab in Israel as part of a doctoral study carried out by Tamar Arens-Arad.

It was also a collaboration with Prof. Daniel Palanker of Stanford University who is the developer of the retinal prosthetic device which is made up of tiny solar cells which are connected to an electrode. In the research the device was placed below the retina of rodents. The study helped to reveal the interactions between prosthetic and natural vision, Mandel said.

According to Mandel, the study shows that restoration of sight for AMD patients with these implants is possible and it supports their hypothesis that the brain can integrate the combination of prosthetic (artificial) and natural vision.