- A tiny electric wire deep in Carlene Morehead's brain
constantly sends signals that tame overactive neurons, restoring her ability
to walk, talk and enjoy time with her family.
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- Mrs. Morehead, 67, has had Parkinson's disease for 20
years. Little more than a year ago, her motor skills rapidly declined after
her response to medications began to change, causing her to oscillate between
having too little mobility and having excessive, uncontrolled movements.
She opted to undergo a surgical procedure called deep brain stimulation.
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- Dr. Cole Giller, associate professor of neurological
surgery and radiology at UT Southwestern Medical Center at Dallas and one
of only three surgeons in Dallas who performs the operation, placed two
tiny electrodes in the subthalamic nuclei on either side of Mrs. Morehead's
brain and wired them to pacemakers implanted in the chest wall just below
her collarbones. The electrodes deliver continuous, high-frequency electrical
stimulation to cells in areas of the brain that control movement. The treatment
results in marked improvement in stiffness, slowness, tremors, weakness
and other disabling symptoms.
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- "The goal of this is to trade electricity for medication,
because the electricity can be delivered at a steady rate that can be adjusted
in small steps to produce the greatest benefits and the least side-effects,"
Dr. Giller said. "The pacemaker is actually turned on by the same
doctor who has been managing the drug therapy of the Parkinson's patient."
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- After her recovery from surgery, Mrs. Morehead's neurologist,
Dr. Padraig O'Suilleabhain, assistant professor of neurology at UT Southwestern,
activated the pacemakers and made a series of adjustments in the following
weeks. During this time, with adjustment of medication and stimulation,
she recovered the ability to function without limitation and without the
up and down response she had been experiencing. Mrs. Morehead now visits
the clinic once every few months for adjustments.
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- "I'll come in, and I'll be having trouble with my
speech, and he'll tweak it a little bit, and I'll start speaking more clearly,"
she said.
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- Dr. O'Suilleabhain said the surgery has significantly
improved the quality of life for 80 percent of his patients who opted to
have it, with dramatic improvements in some.
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- "Some of the effects of stimulation occur in the
first minute after adjustment. A severe tremor can disappear right before
your eyes," Dr. O'Suilleabhain said.
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- Deep brain stimulation was originally approved for use
in the early 1990s to provide electrical stimulation of the thalamus in
patients with disabling tremors. In the last few years, neurological surgeons
have found that placement of the electrodes just under the thalamus - in
the subthalamic nucleus - not only improves tremors, but is effective in
managing the slowness and stiffness and involuntary movements seen in Parkinson's
disease. Researchers have found that the electrical stimulation continues
to provide significant improvements in quality of life for at least five
years after implantation. Balance and mental abilities, which can be impaired
by Parkinson's disease in some people, are usually not helped by the stimulation.
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- The surgery is not a cure for Parkinson's disease. The
gradual loss of nerve cells in the affected part of the brain continues
despite the functional improvements.
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- Deep brain stimulation is replacing surgical procedures
known as pallidotomy and thalamotomy, in which the surgeon actually creates
holes in specific areas of the brain. Unlike the older procedures, deep
brain stimulation is reversible, adjustable and poses less risk.
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- Dr. Giller has developed a unique method of pinpointing
the location of the structure in the brain targeted for electrode implantation.
He inserts a wire with a tiny flashlight on the tip to illuminate the area
of the brain and then analyze its optical properties. Dr. Giller has used
the optical probe to guide his placement of the electrode in 130 deep brain
stimulation procedures, including Mrs. Morehead's.
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- "We can distinguish gray matter from white matter
very elegantly," Dr. Giller said. "It is very easy, very quick,
and we are the only ones in the world to use optical technology to do this."
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- Eleven months after Mrs. Morehead's surgery, she and
her husband, Randall, had a glimpse of what life might have been without
it. Two days before Christmas, a magnetic device in a department store
shut off one of the pacemakers in her chest. Within hours, she could not
walk or talk.
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- "By dinner time that night, I was crawling,"
she said. "My husband had to carry me into the doctor's office,"
she said.
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- Dr. O'Suilleabhain reactivated the pacemaker, and she
was able to walk within an hour.
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- Mr. and Mrs. Morehead, who met in high school in Paradise,
have been married 43 years. The couple has five children and 12 grandchildren.
The way Mrs. Morehead sees it, enjoying time with her husband and family
is what life is all about.
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- "We have been very pleased with the way this turned
out," Mr. Morehead said.
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- Sceince Daily.com
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