Creative Use of Materials for Retinal Implants

Artificial Retina Gets Diamond Coating

Second Sight, a company currently focusing on developing a bionic eye that will help people who have lost vision through diseases such as retinitis pigmentosa and macular degeneration. The silicon chip retinal implant is a device that bypasses diseased cells in the back of the eye by electrically stimulating the healthy cells that lie beneath them. The patient than acquires vision by using glasses with a small video camera that sends digitized images to the implant using radio waves. Although the theory was sound, scientists had a hard time figuring out how they could implant a piece of complex machinery into the eye without getting the circuitry damaged via reaction with the retinal fluid. The solution came in the form of an ultrananocrystalline diamond film.

When one hears the word diamond there is a tendency to envision a shiny stone set in a ring or displayed in a flashy showcase. However, current technology allows for the chemical formation of tiny diamond crystals (five millionths of a millimeter across) that can be grown directly onto a chip. This new film fulfills all of the necessary criteria for a coating as materials before hand had never succeeded in doing. It is safe, long-lasting, electrically insulating, and tough. The durability of materials used in bionic eyes is always an important point for vision is something that one will use as long and he or she is living.

In the article, there is no mention of the price of an artificial retinal implant, which must be considered for, realistically, a company will invest in research only if there is a possibility of profit. A diamond coating may be a great step forward in creating a device that has the potential of being used in human patients, but how this will affect the price tag on a retinal implant will be a vital factor for future users.

web link: http://www.nature.com/news/2005/050331/full/news050328-9.html