Artificial eyes make Franklin's vision a reality

  • 2000-01-20
  • By TBT staff
NEW YORK - A man blind for 26 years after an injury can now "see,"
using an artificial engineering system comprised of a tiny TV camera
and an ultrasonic distance sensor which has allowed him to use the
subway and to surf the Internet.

Reported in several journals, including a periodical issued by
American Society of Artificial Internal Organs, the system depends on
more than 30 years of bio-engineering by the Dobelle Institute in New
York and its affiliates on Long Island and in Switzerland.

The system, called the "Dobelle Eye," enables a totally blind person
to achieve visual acuity of about 20/400, in a narrow visual
"tunnel." It consists of a sub-miniature television camera and an
ultrasonic distance sensor, both of which are mounted on a pair of
eyeglasses. The sensors connect through a cable to a miniature
computer, which is worn in a pack on a person's belt. After
processing the video and distance signals, the computer uses
sophisticated computer-imaging technology, including edge-detection
algorithms to simplify the image eliminating "noise."

The computer then triggers a second micro-computer that transmits
pulses to an array of 68 platinum electrodes implanted on the surface
of the brain's visual cortex. Bringing wires through the skin for
over two decades without discomfort or infection is one of many
independent inventions that has made the new visual prosthesis

When stimulated, each electrode produces one to four closely spaced
phosphenes, which have been described as resembling "stars in the
sky." This white phosphene on a black background "map" is roughly
eight inches by two inches at arms length.

The patient in the study reported in ASAIO Journal is a 62-year-old
man who was totally blinded by trauma when he was 36 years old. After
learning to use the system and "read" the display, the patient is now
able to read two inch tall letters at a distance of five feet,
representing a visual acuity of about 20/400.

Although the relatively small electrode array produces tunnel vision,
the patient is also able to navigate in unfamiliar environments
including the New York City subway system. By replacing the
sub-miniature television camera with a special electronic interface,
the patient is also learning to "watch" television, use a computer,
and gain access to the Internet.

"The development of an artificial eye that can enable the blind to
"see" realizes a prediction made by Benjamin Franklin when he
reported the discovery of electricity in 1751," said Dr. William H.
Dobelle, founder of the Dobelle Institute.

"Our progress represents the work of more than 300 scientists,
engineers and physicians who contributed to various aspects of the
project. With further refinements, including larger arrays of
electrodes and more powerful computers, the system is expected to
provide a "cure" for most types of pediatric and adult blindness.
Brains of sighted people respond to stimulation like those of blind
people, so the system may also be useful for people with very low

The computer package employed in the initial system was the size of a
large bookcase and weighed several thousand pounds. After six
generations of improvement over the last 21 years, the external
electronics package has now been miniaturized so it is about the size
of a dictionary and weighs approximately ten pounds, including

Dr. Dobelle's first human experiments in this artificial vision
project took place in 1970 and involved cortical stimulation of 37
sighted volunteers undergoing surgery on the occipital lobe under
local anesthesia to remove tumors and other lesions. Three blind
volunteers were then temporarily implanted with electrode arrays to
stimulate the visual cortex. Subsequent experiments involved four
blind volunteers who were implanted with permanent electrode arrays
employing percutaneous connecting pedestals.

The Dobelle system's electrodes and connecting pedestal were
surgically implanted in two blind volunteer's brains in 1978 at the
Columbia-Presbyterian Medical Center in New York City. Both have
retained their implants. One is the subject of the study reported in
the ASAIO Journal.

Dr. Dobelle said that the new artificial vision systems are expected
to be made available, on a limited commercial basis, starting later
this year.

The Dobelle Institute and its commercial affiliates in Long Island,
NY and Zurich, Switzerland constitute one of the world's most
sophisticated organizations for education, research, development,
manufacturing and clinical implementation of medical devices. Over
the last 30 years, the Dobelle Institute has been responsible for the
design, manufacture and distribution of other neurological
"pacemakers" to control breathing, intractable pain and the
urogenital system of about 15,000 patients in more than 40 countries.

These clinical systems have gained full regulatory and reimbursement
approval from the U.S. Federal Drug Administration, Medicare and
analogous foreign agencies.