NEUROSCIENCE INSTITUTE
NEUROSCIENCE INSTITUTE
STORM CHASER
REWIRING THE MIND
CHILDREN’S HOSPITAL COLORADO’S NEW
ROBOT HELPS PERFORM BRAIN SURGERY
BETTER, FASTER, AND WITH MORE PRECISION
HOW ELECTRODES IMPLANTED DEEP IN THE BRAIN CAN
HELP MUSCLE CONTROL
The patient, a 17-year-old girl, lies anesthetized, very still. Her long hair
drapes the lip of the operating table.
“Does anyone have a ponytail holder?” says Children’s Hospital Colorado’s
Brent O’Neill, M.D. Then Dr. O’Neill and Catherine McClung-Smith, M.D.,
both brain surgeons, comb the patient’s hair.
The patient has suffered debilitating, near-constant seizures since she was
4 years old. Basically electrical storms in the brain, seizures originate from a
central epicenter or lesion. Remove that lesion and the seizures stop.
The tricky part is finding it. The storms spread at the speed of light, making
their centers hard to target. By placing electrodes into the brain, doctors
can record seizure activity over a week, locate the epicenter, and take it out.
Those electrodes have to get there first. One placement method is to
remove a section of the skull and place a grid of electrodes on the surface
of the brain. Less invasive and more precise than the craniotomy and grid
is frame stereotaxy. That surgery involves essentially scaffolding a patient’s
head and mechanically calculating the exact location and angle to drill
holes in the skull and then place electrodes one by one. The problem is that
each electrode can take a half hour or more to place, and over the course
of placing 10 or 20, an operation can drag on for many anesthetized hours.
It’s hard on doctors and patients alike.
Dr. O’Neill’s new surgical assistant, a robot called ROSA, cuts the placement
time per electrode to five minutes.
With the help of ROSA, one of only about 20
robots of its kind in North America, each step of the
operation has been meticulously planned in advance.
ROSA’s screen displays each site on images of the patient’s skull, along
with the evidence of a lobectomy she underwent at 10 years old: a ragged
rectangle in the bone, held in place with titanium clips. It worked, but the
seizures came back.
Now, Dr. O’Neill simply presses a foot pedal to align the robot with the
next site. He can then drill the next tiny hole for introducing an electrode.
By eliminating the need to constantly recalibrate, ROSA increases not only
efficiency but also precision, minimizing risk.
BRENT O’NEILL, M.D.
Over the next week, Children’s Colorado epileptologist Pramote Laoprasert,
M.D., along with a team of electrophysiologists and neuropsychiatrists, will
isolate the epicenter and electrify electrodes of interest to prove the target
area has no vital neurological function. Dr. O’Neill will remove the lesion.
Once again, the patient will be seizure-free.
Firing neurons sound a lot like
dial-up modems: the noise of
static, pulses, clicks. It is, in fact,
the same language. Like modems,
neurons communicate in binary:
on, off, on, off.
“You can listen and see the pattern,”
says Children’s Hospital Colorado
neurologist and movement disorder
specialist Abbie Collins, M.D. “The
frequency of spikes tells you what
part of the brain you’re in.”
The part of the brain that interests
Dr. Collins is the basal ganglia — the
center, at the core of the brain, of
voluntary movement.
Wiring problems in the basal
ganglia can lead to adult diseases
like Parkinson’s and essential
tremor, both of which benefit from
a treatment called Deep Brain
Stimulation (DBS), which implants
electrodes deep in the basal ganglia
to stimulate or inhibit misfiring
neurons — and gets impressive
results. Pediatric neurologists and
neurosurgeons are increasingly
exploring DBS as a treatment for
kids with diseases like dystonia,
a serious motor impairment that
causes stiffening of the muscles.
“When you raise your arm,”
Dr. Collins says, “your bicep has to
contract, your tricep has to relax,
and your deltoid needs to hold the
position. In dystonia, because of
faulty wiring in the basal ganglia,
your tricep doesn’t get the signal to
relax. You’re just constantly fighting
your own muscles to make even
basic movements.”
ABBIE COLLINS, M.D.
DBS can help, but the results
have been inconsistent. “We’re
trying to understand who’s going
to respond to DBS, and how they’re
going to respond.”
To address that question,
Dr. Collins and
Children’s Colorado
neurosurgeon Aviva
Abosch, M.D., Ph.D., are
working to correlate
brain-imaging data
with clinical data
gathered through
dozens of means.
Many of those means are unique
to Children's Colorado's program,
including the use of the Center for
Gait and Movement Analysis (see
p. 25), where researchers can study
nuances of movement using
ultra-sensitive instruments.
So doing, Drs. Collins and Abosch
hope to gain much-needed insight
into a complex disorder — and into
the workings of the growing brain.
“So much has to happen to execute
even a simple motor command,”
Dr. Collins says. “The concept ‘move’
is actually very complicated.”
And they hardly even messed up her hair.
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