Here it is. The first direct augmentation of the optic nerve to
generate images with a practical device. It is even good enough to
be helpful. We will now experience continuous improvement until, we
develop the larger device with a broader spectrum used by ET.
In the meantime, this is good enough to eliminate the need for a cane
or a seeing eye dog.
As stated it can only get better and denser in terms of data flow.
Device Offers
Partial Vision for the Blind
PAM BELLUCK
Published: February
14, 2013
The Food and Drug
Administration on Thursday approved the first treatment to give
limited vision to people who are blind, involving a technology called
the artificial retina.
The device allows
people with a certain type of blindness to detect
crosswalks on the street, the presence of people or cars, and
sometimes even large numbers or letters. The approval of the system
marks a milestone in a new frontier in vision research, a field in
which scientists are making strides with gene therapy,
optogenetics, stem cells and other strategies.
“This is just the
beginning,” said Grace Shen, a director of the retinal diseases
program at theNational Eye Institute, which helped finance the
artificial retina research and is supporting many other blindness
therapy projects. “We have a lot of exciting things sitting in the
wings.”
The artificial retina
is a sheet of electrodes implanted in the eye. The patient is also
given glasses with an attached camera and a portable video processor.
This system, called Argus II, allows visual signals to bypass the
damaged portion of the retina and be transmitted to the brain.
With the artificial
retina or retinal prosthesis, a blind person cannot see in the
conventional sense, but can identify outlines and boundaries of
objects, especially when there is contrast between light and dark —
fireworks against a night sky or black socks mixed with white ones.
“Without the system,
I wouldn’t be able to see anything at all, and if you were in front
of me and you moved left and right, I’m not going to realize any of
this,” said Elias Konstantopolous, 74, a retired electrician in
Baltimore, one of about 50 Americans and Europeans who have been
using the device in clinical trials. He said it helps him
differentiate curbs from roads, and detect contours of objects and
people. “When you have nothing, this is something. It’s a lot.”
The F.D.A.
approved Argus II, made by Second Sight Medical Products,
to treat people with severe retinitis pigmentosa, in which
photoreceptor cells, which take in light, deteriorate.
The eyeglass camera
captures images, which the video processor translates into pixelized
patterns of light and dark, and transmits them to the electrodes. The
electrodes then send them to the brain.
“The questions that
this particular device raised for F.D.A. were very new,” said Dr.
Malvina Eydelman, the F.D.A.’s director for the Division of
Ophthalmic and Ear, Nose, and Throat Devices. “It’s a big step
forward for the whole ophthalmology field.”
About 100,000
Americans have retinitis pigmentosa, but initially between 10,000 and
15,000 will likely qualify for the Argus II, according to the
company. To be eligible, people must be over 25, have previously had
useful vision, and be so visually impaired that the device would be
an improvement.
But experts said the
technology holds promise for others who are blind, especially those
with advanced age-related macular degeneration, the major
cause of vision loss in older people, affecting about two million
Americans. About 50,000 would be impaired enough for the device to
help, said Dr. Robert Greenberg, Second Sight’s chief executive.
In Europe, Argus II
received approval in 2011 to treat severe blindness from any type of
outer retinal degeneration, although so far it is marketed there for
retinitis pigmentosa. In the United States, additional trials are
necessary for such approval.
Eventually, the
company plans to implant electrodes directly into the brain’s
cortex to “allow us to address blindness from all causes,” Dr.
Greenberg said.
Initially, Argus II
will be available at seven hospitals in New York, California, Texas,
Maryland and Pennsylvania. It will cost about $150,000, excluding
surgery and training. Second Sight said it was optimistic that
insurance would cover it.
Argus II was developed
over 20 years by Dr. Mark S. Humayun, an ophthalmologist and
biomedical engineer at the University of Southern California. Some
financing came from private sources and the National Eye Institute,
the National Science Foundation and the Department of Energy, all
federal agencies.
Dr. Humayun said he
envisioned applying the technology to other conditions than
blindness, implanting electrodes in other parts of the body to
address bladder control problems, perhaps, or spinal paralysis.
“We don’t think of the human body as an electrical grid, but it
runs off electrical impulses,” he said.
The Argus II was
approved under a special F.D.A. program designating it a
“humanitarian use device,” which Dr. Eydelman said applied to
therapies that would be used for fewer than 4,000 people a year.
Argus II is only the 57th humanitarian device exemption granted by
the agency. Companies applying for humanitarian device approval can
conduct much smaller clinical trials — Second Sight submitted data
on only 30 patients — and must only demonstrate safety and
“probable benefit,” not proof of effectiveness, Dr. Eydelman
said.
The F.D.A. worked with
Second Sight to develop ways to measure that benefit, including tasks
like walking on a sidewalk without stepping off, and matching black,
gray and white socks.
Of the 30 Argus II
clinical trial patients, 11 experienced a total of 23 negative
effects, the F.D.A. said, including retinal detachment and
erosion of the clear covering of the eyeball.
Dr. Eydelman said the
company had “taken substantial steps” to address safety concerns,
making “many device modifications.” Dr. Greenberg said only two
people needed to have the implant removed. An F.D.A. advisory panel
voted unanimously last September to recommend approval, finding that
benefits outweighed the risks.
Some patients see more
improvement than others, for reasons the company has not been able to
determine. Kathy Blake of Fountain Valley, Calif., said she has had
success with a Second Sight exercise to see if patients can identify
large numbers or letters on a computer screen.
Dean Lloyd, a lawyer
in Palo Alto, Calif., said he initially wondered, “Is it really
worth all the time and expense? I, at first, did not think so.”
Early on, only nine of the 60 electrodes were working, but over time
his implant was adjusted so more electrodes responded, and now 52 of
them work. He can see flashes of color, something not every patient
can, and he wears the glasses and video processor constantly.
“If I don’t wear
it, it’s like I don’t have my pants on,” he said. “I’ve
even fallen asleep with the blooming thing.”
Stephen Rose, the
chief research officer for the Foundation Fighting Blindness,
which supported Dr. Humayun’s very early work but has not financed
it since, said the artificial retina would eventually be only one of
the options to help blind people.
“I think there are
tremendous possibilities,” he said. “I’m not downplaying the
retinal prosthesis, don’t get me wrong. It’s huge for some
individuals, and it’s here now.”
Barbara Campbell, 59,
relishes how the device helps her navigate Manhattan streets, locate
her bus stop, and spot her apartment building’s foyer light while
riding in a taxi.
Most exciting, though,
is how it enhances her experience of museums, theater and concerts.
At a performance by
Rod Stewart, “I could definitely see his hair,” which was
white-blond under the lights, she said. At a concert by Diana Ross,
even though Ms. Campbell sat far away from the stage, she said Ms.
Ross “was wearing a sparkly outfit, and I could see her.”
No such luck at a
performance by James Taylor, though. His low-key clothing created no
contrast for the artificial retina to register. Alas, Ms. Campbell
said, “He wasn’t so sparkly.”
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