Chemoretina: An alternate approach to retinal prosthesis: Visual stimulation strategy using chemicals

Hereditary degenerative diseases of retina (such as Retinitis pigmentosa and age related macular degeneration), cause photoreceptor cell loss leading to progressive visual impairment. Since there is no medical treatment to reverse / overcome the effects of photoreceptor loss, restoring vision with the aid of a prosthetic seems to be the only option. Different types of prosthesis incorporating different geometries and design of multielectrode arrays have been developed to be surgically placed in and around retina. However patients implanted with these devices have been able to see only flickers of light (or phosphenes). Therefore in the present work we have come up with an alternate strategy of stimulating retina through chemicals: Chemoretina. Briefly, our idea involves stimulating voltage gated sodium channels of retinal bipolar cells using drugs, in a manner analogous to photoreceptor stimulation. This paper illustrates our approach to Chemoretina and current developments so far.