Argus II Available for CHM Patients
October 29th, 2014 by Danny Boren
What is the Argus II?
The Argus® II Retinal Prosthesis System (“Argus II”) is also known as the bionic eye or the retinal implant. It is intended to provide electrical stimulation of the retina to induce visual perception in blind individuals. It is indicated for use in patients with severe to profound retinitis pigmentosa and CHM is a subset disease of RP.
Argus II has been implanting devices in the U.S. since January 2014.
How does the Argus II work?
A miniature video camera housed in the patient’s glasses captures a scene. The video is sent to a small patient-worn computer (i.e., the video processing unit – VPU) where it is processed and transformed into instructions that are sent back to the glasses via a cable. These instructions are transmitted wirelessly to an antenna in the retinal implant. The signals are then sent to the electrode array, which emits small pulses of electricity. These pulses bypass the damaged photoreceptors and stimulate the retina’s remaining cells, which transmit the visual information along the optic nerve to the brain, creating the perception of patterns of light. Patients learn to interpret these visual patterns with their retinal implant.
In a recent telephone interview with Gary Peyser, Customer Service Manager at Second Sight Medical Products, Inc, Gary confirmed that an advanced CHM diagnosis would satisfy the inclusion criteria and allow patients to be considered for the ARGUS II. In addition to the Choroideremia diagnosis, the following principles would need to be established:
* Patient must be at least 25 years in age
* Level of vision must be very poor; bare light perception
Multiple medical centers around the country are able to perform the procedure. 80% of the cost would be covered by Medicare and the remaining balance covered by secondary insurance (however this would vary with an individual’s insurance coverage).
ARGUS II would work specifically with the eye which contains the least amount of sight left. The procedure would be under general anesthesia and take between 2-4 hours. The microchip would be applied so that the central line of vision, where the chip lies, would provide 22 degrees of vision – 11 degrees on each side, thus all other peripheral vision would be lost.
Each patient will have individual outcomes, however generally speaking images will be seen in black and white with shades of grey. Edges of buildings, doorways, curbs and crosswalk stripes can typically be seen. Gary stressed the need to continue to use adaptive equipment such as a guide dog or cane, but the ARGUS II can certainly provide increased awareness and safety. Facial images most likely would not be seen, however one should be able to discern figures.
CRF member, Dave Schmidt in Northfield, Minnesota has been given preliminary approval as a possible candidate to receive ARGUS II at the Mayo Hospital in Rochester, Minnesota. He will be meeting with physicians later in November with a hopeful procedure scheduled in early 2015.
Please keep in mind, ARGUS II is for advanced CHM patients. If you would like more information, please visit: http://2-sight.com .
Specific questions can be made of Mr. Gary Peyser at Second Sight. He will be able to provide information and if you meet necessary criteria, refer you to the appropriate medical institution in your area that is participating with Second Sight & the ARGUS II.
Gary can be reached at (855)756-3703.