Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Ophthalmologists implant five patients with artificial silicon retina microchip


Solar Cell Implant May Restore Some Sight for the Blind

Ophthalmologists at Rush University Medical Center implanted Artificial Silicon Retina (ASR) microchips in the eyes of five patients to treat vision loss caused by retinitis pigmentosa (RP). The implant is a silicon microchip 2mm in diameter and one-thousandth of an inch thick, less than the thickness of a human hair. Four patients had surgery Tuesday, January 25. The fifth patient is scheduled for a later date.

Rush principal investigator Dr. John Pollack performed the surgeries with Dr. Kirk Packo, Dr. Pauline Merrill, Dr. Mathew MacCumber, and Dr. Jack Cohen. All are members of Illinois Retina Associates, S.C., a private practice group and are on the Rush faculty. Patients leave the hospital the same day and will be followed for two years as part of the study, and then indefinitely. The patients were recruited from a pool of about 5,000 applicants.

The implants are designed for people with retinal diseases such as macular degeneration and retinitis pigmentosa, which cause blindness and vision impairment in about 10 million Americans. More than one million of these people are legally blind.

"As is commonly seen in with retinitis pigmentosa, these patients all have severe narrowing of their visual fields down to a very small central circle, and all patients in the study are legally blind," says Pollack.

The Artificial Silicon RetinaTM (ASR) was invented by Dr. Alan Chow, pediatric ophthalmologist and Rush faculty member, who developed the chip and founded Optobionics, with his brother Vincent, vice president of engineering. Optobionics is located in Naperville, Illinois.

"This is an expansion of the study of the first 10 patients completed in 2002," says study investigator Dr. Kirk Packo, who oversees the three participating sites. The sites are Johns Hopkins School of Medicine, Baltimore, Emory University School of Medicine/Atlanta VA Medical Center and Rush.

Pollack says the current protocol has been modified to reduce the likelihood of inadvertant scientific bias. "We operated on the right eye of each of the initial 10 patients. For the next 20 patients we will randomly select which eye will receive the ASR chip. In addition, post-operative vision testers will be masked as to which eye received the ASR chip implant. The current study is being performed at these study centers in order to independently validate previous studies performed by Optobionics."

The first 10 patients all reported some degree of improvement in visual function, says Pollack. "Improvement in visual function was variable and included the ability to read letters, improvement in color vision, and expansion of their visual field. Some patients gained new ability to recognize facial features -- something that they were unable to do before ASR chip implantation. Some patients have experienced improvement in activities of daily living such as improved ambulation-not bumping into objects around the house, and reading the time on a clock."

Still in Phase II clinical trials, Pollack cautions it is still too early to determine what percentage of patients might experience improvement in vision and what resolution capability these patients might eventually have. "Although we hope that all patients receiving the chip will experience some improvement in visual function, we can’t say for sure how these patients will respond to this new treatment since this is still an experimental trial. If this study and future studies show safety and efficacy of the chip and it’s approved by the FDA, it could be as soon as three to five years that this technology would be available to others."

Surgical Information

The ASR chip contains approximately 5,000 microscopic solar cells that convert light into electrical impulses. The purpose of the chip is to replace damaged photoreceptors, the "light-sensing" cells of the eye, which normally convert light into electrical signals within the retina. Loss of photoreceptor cells occurs in persons with retinitis pigmentosa (RP) and other retinal diseases.

The microsurgical procedure starts with three tiny incisions in the white part of the subject’s eye, each incision no larger than the diameter of a needle. Through these incisions, the surgeons insert a miniature cutting and vacuuming device that removes the gel in the middle of the eye and replaces it with saline. They then make a pinpoint opening in the retina through which they inject fluid to lift up a portion of the retina from the back of the eye, creating a small pocket in the "subretinal space" just wide enough to accommodate the ASR.

The surgeons then enlarge the pocket opening and insert the implant into the subretinal space. Finally, they reseal the retina over the ASR, insert air into the middle of the eye to gently push the retina back down over the device, and close the incisions. Over a period of 1 week the air bubble is resorbed and replaced by fluids created within the eye.

According to Chow, "The use of the subretinal space to hold a device that artificially stimulates the retina seems a logical step in replacing the loss of photoreceptor cells of the retina. If the implant is tolerated well and is able to successfully stimulate the retina, it may open up new opportunities for restoring sight in patients with the end stages of retinitis pigmentosa."

Mary Ann Schultz | EurekAlert!
Further information:

More articles from Health and Medicine:

nachricht Resolving the mystery of preeclampsia
21.10.2016 | Universitätsklinikum Magdeburg

nachricht New potential cancer treatment using microwaves to target deep tumors
12.10.2016 | University of Texas at Arlington

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>