Arthur Hirsch wrote:
>...showing a DBS operation for tremor.
Dan Rather's last comment was that this may soon help victims of
Parkinson's Disease. He said, to this effect, "the treatment has
already been approved in Europe. It will be tested in the U.S. starting
this fall, and it may be available for PD patients within two years."
--------------------------------------
Art,
Brain monitor approved FDA clears way for
'pacemaker', which can control tremors
ALAN BAVLEY-Medical Writer
5 August 1997
The tremors in Maurice Long's head and hands became so
jarring, he was too embarrassed to leave the house.
Then surgeons at the University of Kansas Medical Center
gave Long an experimental "brain pacemaker" last year that
short-circuited the nerve impulses giving him the shakes.
After he got out of the hospital he was out on the golf
course with steady hands, putting better than he had in years.
"I was just tickled pink," the 72-year-old Hutchinson, Kan., man
said. "It's a darned miracle."
On Monday, the Food and Drug Administration approved the
"brain pacemaker" for general use, clearing the way for thousands
of people with Parkinson's disease or essential tremor to gain
relief from their disabling conditions.
About 500,000 people in the United States have Parkinson's
disease and 4 million have essential tremor, a progressive
disease that tends to run in families.
"It's one of the most impressive things I've seen in
medicine," said KU Medical Center neurologist William Koller, who
has implanted the device in about 60 patients over the last three
years as part of the clinical trial that led to FDA approval.
"Some of these patients couldn't even drink a glass of
liquid or brush their teeth. Life was a constant frustration."
The Activa Tremor Control System manufactured by Medtronic
is a 1.7-ounce, battery-powered electronic pulse generator that
blocks faulty brain signals that cause tremors. It looks much
like the cardiac pacemakers the Minneapolis-based Medtronic is
known for.
To implant the device, surgeons drill a hole through the
skull and pass electrodes deep into the thalamus area of the
brain.
Connected to the electrode is an insulated wire that passes
under the skin of the scalp and neck and attaches to the pulse
generator. The generator is positioned under the skin near the
collarbone.
Together, the device and surgery cost about $25,000. Koller
said he thinks insurance companies eventually will cover it.
Before going to bed, patients can turn the device off to
save battery power by passing a magnet over their chests. A
second pass in the morning turns it on.
Separate devices are needed for each side of the body. But
because there is little evidence yet on double implants, the FDA
has approved the use of only one per patient. It will usually be
used to control tremors in the hand the patient uses most.
Of 196 Parkinson's and essential tremor patients who have
received the pacemaker in clinical testing, almost all improved.
In more than half, tremors were reduced significantly.
"It could have major benefits for both kinds of patients,"
said Judy Rosner, executive director of the Chicago-based United
Parkinson Foundation. She predicted that the device would be
appropriate for about 20 percent of patients, those who have
severe cases that do not respond to drugs.
Parkinson's disease and essential tremor are progressive
conditions called movement disorders. Essential tremor usually
has no symptoms other than tremor.
Parkinson's disease also often includes stiffness of limbs
and joints, slowness of movement and impaired balance and
coordination. The device is not intended to relieve these other
Parkinson's symptoms.
Drugs for both essential tremor and Parkinson's disease have
significant drawbacks, Rosner said.
About one-third of essential tremor patients do not get good
results from the drugs, and many suffer objectionable side
effects such as impotence and drowsiness.
Parkinson's disease drugs work primarily on muscle rigidity,
rather than tremor.
"Tremor is usually the last symptom to respond," Rosner
said.
When dosages are raised high enough to be effective against
tremors, patients often experience twitching and jerking.
Long had suffered essential tremor for 14 years. The
condition was becoming worse and the medications he took less
effective.
"I couldn't write my name or drink a cup of coffee without
spilling it," he said.
Now, with the brain pacemaker, he is leading an active life.
He credits it for the eight-stroke reduction in his golf
handicap, and it has given him another advantage at the game.
One time at the golf course, Long went in with his pacemaker
turned off and made pre-game bets with the other players. Then he
turned it on.
"They only let me do that once," he said.
--
Judith Richards, London, Ontario, Canada
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