The Best kinds of Retinal Implants

The most prevalent forms of retinal implants in this day of increasing research in the area are the epiretinal and subretinal implants. In reality, neither is perfect, and both have their positives and negatives, just as you would expect from a growing field of research. But in my opinion, the aspects of one clearly outweigh the other. I believe that overall positive aspects of the epiretinal implant make it the retinal implant of choice in these situations of medical blindness.

The epiretinal implant is one that is placed in the inner retinal membrane. It requires no photoreceptors and relies upon an external camera of sorts to send it information that it can later relay to the ganglions in the eye by way of electrodes. The obvious limitations to this lie in its reliance on external sources of infomation, rather than the neurons of the optic nerve itself, as does the subretinal implant, which is placed between the pigment epithelial layer and the outer layer of the retina. But I also believe that therein lies the appeal to the epiretinal implant. The fact that it wouldn't need to rely on possibly diseased or dying cells makes it at least seem more efficient.

Among the detractors to the epiretinal implants is the fact that because they rely on an external source, the device itself must do the extraordinarily difficult task of interpreting the visual information into electrical signals and commands. Despite this enormous task, the epiretinal seems to me to be the better option considering that it mustn't rely on damaged cells. The use of external cameras and their images (if interpreted properly) also "optimizes the signal received by the implants" (Optics Report).

Of course, assumptions should be made lightly concerning these implants, especially during their experimental phases. The best information and determination will come later from human testing (when approved), seeing as the implants have seen most of their testing in blind and healthy rats, cats, and dogs.\

1. "Will retinal implants restore vision?". Zrenner, Eberhart. Science 2002. .
2. "Optoelectronic implants to treat visual diseases." Optics report. June 14, 2003. .