In just over 10 years, the technology that has been developed to help people see has been amazing. While medical research continues to move forward to find treatments and potential cures of the future, those with the technological know-how have created ways for people to see NOW. Here is a very brief look at some of these technologies.
Technology for Vision
One of the pioneers in the field of vision technology, Second Sight started in 1998, and they are now currently producing the second version of their device. It is made up of two parts:
The Implant: Requiring a 4-hour surgery, a device is surgically implanted in the eye on top of the retina, and along the outside of the eye. It includes an antenna, an electronics case, and an electrode array.
The External Equipment: It includes glasses, a video processing unit (VPU) and a cable.
In a healthy eye, photoreceptors (rods and cones) in the retina convert light into tiny electrochemical impulses that are sent to the brain, where they are translated into images. If the photoreceptors don’t function correctly your brain can’t produce images. The Argus II Retinal Prosthesis System (“Argus II”) is designed to bypass the damaged photoreceptors.
A miniature video camera housed in the patient’s glasses captures an object. The video is sent to the small VPU that the patient wears. It is then processed and transmitted back to the glasses via a cable. This information is sent wirelessly to the antenna in the implant and signals are sent to the electrode array, which emits small pulses of electricity. These pulses bypass the damaged photoreceptors and stimulate the retina’s remaining cells. The visual information is then sent to the brain to create the perception of patterns of light which patients can learn to interpret as objects. Significant training is required to use the system.
The implant is designed to give you a visual field of about 3.5 inches by 6.5 inches at arm’s length; however, the actual size of light you see may be larger or smaller. Since it is strictly based on light, there is no color perception.
Another system that relies upon the user wearing glasses is eSight which started in 2012. While the Argus II is for people that have very little or no vision, the eSight is for people with low vision or that are legally blind. eSight glasses require the individual to have a certain degree of sight remaining to be successful. If you can only see shadows you probably don’t have enough remaining sight for the glasses to work for them.
This system is also composed of two parts, but it does not require any surgery:
The Headset: It contains a high-definition camera, OLED screens, and the ability to capture and display a real-time video feed. The headset is mounted on carrier frames, which enables eSight’s “bioptic tilt” feature so the user can shift between viewing modes and engage their peripheral vision.
The Controller: A small, lightweight processing unit that adjusts every pixel of the video in real time. It also houses the battery, which powers eSight.
Because most legally blind individuals retain limited sight concentrated in their peripheral vision, their eyes do not receive an adequate signal for the brain to recognize what is being seen. This can create blind spots, blurriness, inability to detect contrast, and other symptoms that reduce vision. eSight is able to significantly corrects these issues by using a high-speed camera, video processing software, a computer processor and the high quality video OLED screens to project a real-time image on the inside of the glasses, allowing people to see.
eSight requires considerably less training than the Argus II. It is intuitive, but as with learning anything new, the more you use it the easier it is to use. It is best to practice on a daily basis.
The CentraSight uses a tiny telescope that is implanted inside the eye. The telescope implant was created to improve for people with end-stage age-related macular degeneration (AMD). The tiny telescope – about the size of a pea – is implanted inside one eye, behind the iris and is barely noticeable in your eye.
In end-stage AMD, the macula, where central vision occurs, is degenerated in both eyes without any healthy macular areas left for detailed central vision. There is no way for the individual to see around the central blind spot in their vision. It does not affect peripheral vision, which is blurry so you can’t use it to read, but you can use it to detect objects and movement.
Once implanted inside the eye, the tiny telescope works like a telephoto lens of a camera. It magnifies images onto the healthy areas of the retina to help improve central vision. Because the image is enlarged it reduces the effect the blind spot has on central vision. The surgical procedure is only performed on one eye because the peripheral (side) vision will be restricted in the eye with the telescope implant. This means the peripheral vision in the untreated eye will need to work in conjunction with the implanted eye. “A person uses the eye with the telescope implant for detailed central vision (such as reading “WALK” signs at a crosswalk). The other eye is used for peripheral vision (such as checking to see if cars are coming from the side).
Training with a CentraSight low vision specialist will be needed to develop the skills you need to use your new vision, such as how to switch your viewing back and forth between the eye with the telescope implant and the eye without the implant. You will still need to wear eye glasses and may need to use a hand-held magnifier with the telescope-implanted eye to read or see fine details clearly. However, in general, less magnification will be needed.
After eight years of research, a Canadian optometrist, Dr. Gareth Webb, has invented a tiny bionic lens that is able to enhance eyesight so that an individual can see three times better than the sharpness of 20/20 vision. The Ocumetics Bionic Lens is a button-shaped lens that can be injected into the eye in eight minutes in a procedure identical to cataract surgery.
As people get older, the lens inside the human eye becomes cloudy over time, causing blurred vision, known as cataracts. The Bionic Lens would be inserted, replacing the person’s clouded lens, similar to the intraocular lenses currently used in cataract surgery.
The Bionic Lens features a patented Ocumetics camera optics system, which is a tiny bio-mechanical camera that is able to shift focus from a close range object to optical infinity – as far as the eye can see – much faster than the human brain.
This device is still not available to the public, but Webb is hopeful that clinical trials will start soon. Depending on regulatory processes in each country, Webb hopes the Bionic Lens will be commercially available by 2017.
Susan DeRemer, CFRE
Vice President of Devlopment
Discovery Eye Foundation