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Huntington Medical Research Institutes
Neura Engineers
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From Battlefielc
to Homefront
T
wo projects are putting HMRI Neu-
ral Engineering researchers on the
front line in care for war fighters on
the battlefield and during rehabilitation
upon their return home.
Both projects require
the unique expertise
for which HMRI's neural
engineers are internation-
ally known and respected.
The two projects are funded by the U.S.
Army'sTelemedicine and Advanced
Technology Research Center (TATRC) and
the Defense Advanced Research Projects
Agency (DARPA).
New deep eye scanner for
fast battleground diagnosis
The TATRC project is concerned with eye
trauma in the battlefield and is done in
collaboration with Dr. Shuliang Jiao and
other investigators at the Department of
Ophthalmology, Keck School of Medicine
at use. One part of the TATRC project,
led by HMRI's Dr. Victor Pikov, aims to
develop a device for eye trauma screen-
ing in the battlefield, while the other part,
led by HMRI's Drs. Douglas McCreery
and Martin Han, will develop an implant-
able device to restore useful vision by
stimulating visual centers of the brain.
This visual prosthesis could be used to
rehabilitate war fighters whose eyes have
sustained very severe injury.
"In the current conflicts, blunt cranial
trauma is the most common injury from
roadside lEDs (improvised
explosive devices)," said Dr. McCreery,
Neural Engineering director. "They get
frontal cranial damage, along with dam-
age to the eyes from blast impact."
There's a "golden hour in which to
provide treatment for best results," he
continued "For example, the golden hour
for a gunshot wound is one hour to get
the patient into surgery."
For eye injuries, that "golden hour" can
stretch into several hours to seek treat-
ment. "For eye trauma, one of the things
that happens is a detached retina and
that must be remedied within hours and
'tacked' down; otherwise the lack of
blood supply will cause the retina to die,"
Dr. McCreery explained.
"They inject a silicone oil into the vitre-
ous (the space between the lens and the
retina of the eyeball) to press down the
retina to reattach it," explained Dr. Pikov.
"Ironically, just as we have to change the
oil in a car, a patient has to have an
Continued on page 2

2. From Battlefieldto Homefront from cover
ophthalmologist
change the silicone
oil in his eye every six
months or so.
"War fighters cannot
open their eyes many
times due to eye lid
trauma or eye bleeding,
so the medics cannot
do a regular ophthal-
mologic screening," Dr.
Pikov said.
"What we are propos-
ing is a novel retinal
testing device that uses
a penetrating electro-
magnetic wave that
can go through the
eyelid, cornea and the
general eye structure
to stimulate the retina
noninvasively to see if
some parts of the retina
are still functional."
Dr. Martin l-lan, Dr. Douglas McCreery, Director of Neural Engineering Program, and Dr.
Victor Pikov.
"By having this diagnostic tool on the battlefield, tests can be
done immediately and, if needed, reattachment of the retina
can be performed by oil injection into the eye, and then keeping
the eyes closed to prevent more injury," he said.
Meeting the need for better artificial limbs
The Department of Defense has been faced with a growing
challenge to develop better prosthetics for wounded war fight-
ers. Today's best artificial limbs have low functionality, and
DARPA needs to upgrade to models with greater dexterity.
brain communication
capability and longevity.
That's where Dr. Han,
the principal investigator
on the DARPA project,
along with Dr. McCreery
and Dr. Pikov, come in.
They will develop a bet-
ter interface between
the brain and prosthetic
limbs for wounded
warriors.
While some existing
prosthetic arms use
signals from the nerves
or muscles, implanting
microelectrodes into the
brain to transmit signals
directly from its neurons
offers users greater
control and more natural
movement. The micro-
electrodes must be as
thin as a single strand of
hairand made of metal
or metal-like silicon. Moreover, Dr. Han has recently created even
thinner and more flexible polymer electrodes.
The team will determine why current brain interfaces intended
to control prosthetic limbs fail after a relatively short time, usu-
ally within a few months. Once that has been determined, the
researchers will develop implantable electrodes to enable con-
trol of complex arm prosthetics by the brain to boost capability
from 2 degrees of movement to 22 degrees, increasing elbow
and wrist rotation and finger movements for greater facility in
grasping and handling objects.
Continued on page 4

3. From Battlefield to Homefront from page 2
In a clinical trial, "intracortical electrodes that recorded motor
signals directly from brain cells could eventually be used to con-
trol the complex robotic arms. However, these electrodes have
shown to be unreliable," said Dr. Han. "That interface between
neurons and prosthetic device is created when a microelectrode
is implanted into the brain to record and decode its instruc-
tions to the robotic arm. When you lose that interface, you lose
robotic control."
Researchers have been trying to answer the question "Why do
these devices fail?" "However, different researchers have used
different surgical techniques, and different devices implanted
into different brain regions," Dr. Han said.
By incorporating four widely used electrode designs into a
hybrid array, HMRI investigators will determine why the mi-
croelectrodes fail to record signals from brain cells ("neuronal
action potentials") for long periods of time.
Instead of stimulating neurons to fire, the microelectrodes use
spontaneous neuronal activity to drive a prosthetic arm in a cer-
tain way, for example, for direction and velocity of movement.
Findings from this study could go beyond prosthetics to ap-
plications for other neurological disorders, including Parkinson's
disease and epilepsy. Dr. Han added. "This could be used for
detecting epileptic seizures," he said. "Before an onset of an
epileptic seizure, there's known to be some subtle change in brain
activity that's hard to detect with current technologies, but with
these electrodes in the brain, they can predict the pending onset
of a seizure before it happens." •
Part of this worl< is sponsored by the Defense Advanced Research Projects
Agency (DARPA) Microsystems Technology Office (MTO), under the
direction ofDr Jack W. Judy as part of the Reliable Neural Technology
Program, through the Space and Naval Warfare Systems Command
(SPAWAR) Systems Center (SSC) Pacific grant No. N66001-11-1-4010.
PAGE 4