Therapies Push Injured Brains and Spinal Cords into New Paths
From: New York Times Online - 08/28/2001
By: Sandra Blakeslee

Birmingham, AL - At a growing number of rehabilitation centers, stroke
patients move around with their limbs tightly bandaged, mummy style. Toddlers
with cerebral palsy are ensconced in partial body casts. Paraplegics are
slung in harnesses and made to walk on treadmills, with automatic equipment
moving their feet. Even the blind are having their brains reconfigured with a
special camera that allows them "see" via a device worn on the tongue. 

Rehabilitation may never look the same. Like engineers in thrall to a new
idea, many of the doctors and therapists who help patients with brain
injuries are using revolutionary insights about the brain to coax the nervous
system into rewiring itself. 

But even as new approaches show promise, much uncertainty remains about which
patients, if any, are likely to benefit from specific treatments. And the
amount of rehabilitation time that is covered by Medicare and private
insurers is shrinking just as the patients' options are growing. 

The new rehabilitation strategies stem from the realization that the brain
makes new neurons in adulthood, and from indications in animals that these
cells may be able to migrate to areas damaged by disease or injury. Moreover,
researchers know that activity can keep neurons from atrophying. 

The challenge is translating that increasingly dynamic view of the brain into
useful therapies, said Dr. Susan Fitzpatrick, vice president of the James S.
McDonnell Foundation in St. Louis, which promotes research on the mind, the
brain and behavior. 

Of the half-million people who survive strokes each year, a third recover
spontaneously. A quarter are too severely injured to benefit from therapy.
The rest can be helped to varying degrees by conventional therapy. It is too
soon to know how many people may be helped with the new approaches. 

Most physicians adopt a wait-and-see attitude after a brain injury because
they are pessimistic, said Dr. Jordan Grafman, a neurologist at the National
Institute of Neurological Diseases and Stroke. 

"They recommend rehabilitation therapy more out of a sense that something has
to be done than a real expectation that it will help the patient," Dr.
Grafman said. 

To assess where the new therapies are headed, the McDonnell Foundation
invited 30 leading research scientists and rehabilitation therapists to
Birmingham in July for a two-day meeting. 

Dr. Pamela W. Duncan, director of the Center on Aging at the University of
Kansas Medical Center in Kansas City, said at the meeting that the new
insights should be greeted cautiously. "The insights hold great promise but
we must proceed with caution," Dr. Duncan said. "It is premature to know
exactly how beneficial the therapies may be for most patients."  

Some patients are very sick and confused, Dr. Duncan said, and nothing much
can help them, while others may benefit enormously. So far, she said, there
are more questions than answers: Who decides which patients are candidates
for the therapies? What is the definition of improvement or recovery? And,
more important, who will pay? 

A few years ago, Dr. Duncan said, stroke patients who qualified for Medicare
services got three weeks of rehabilitation care. Now they get about 11 days.
Medicare is cutting back because the cost of rehabilitation services rose to
$30 billion in 1996 from $2.5 billion in 1986. 

When patients with brain and spinal cord injuries hear about seemingly
miraculous new treatments, said Dr. Anne Shumway-Cook, an associate professor
and rehabilitation therapist at the University of Washington, they pressure
therapists to provide them. 

Frustrated that ordinary methods - like teaching a patient to get dressed
using only one hand - do not do much, especially in 11 days or so, many
therapists are offering the new treatments without quite knowing how they
work, Dr. Shumway-Cook said. If a method fails, no one knows if it was a
problem with the technique or with the way it was being delivered. 

The new rehabilitation methods try to kick-start the process of self-repair
in the brain or spinal cord. One way to do that appears to be to give
amphetamines several weeks after a stroke; that strategy is being tested in a
large multicenter trial. 

The therapies that rely on restricting or encouraging movement are based on
the idea that after a brain injury, a number of brain cells are killed
outright, but many cells surrounding the injury are merely stunned. The
therapies try to wake up the cells that have been stunned, said Dr. Edward
Taub, a neuroscientist at the University of Alabama. 

"Right after a stroke, a limb is paralyzed," Dr. Taub said. "Whenever the
person tries to move an arm, it simply doesn't work." Even when all the cells
that represent the arm in the brain are not dead, he said, the patient,
expecting failure, stops trying to move it. "We call it learned non-use,"
Dr. Taub said. 

When the patient relies on the good arm, the recovery of the use of the bad
arm becomes less likely. 

One approach, called constraint-induced movement-based therapy, rests on the
principle that lots of practice can reorganize the brain, said Dr. Wolfgang
Miltner, a neuroscientist at the Friedrich-Schiller University of Jena in
Germany. But it has to be carried out in a specific manner. 

"You don't just repeat movements," Dr. Miltner said. "You have to shape them,
which means thinking about the elements of each movement."  

In the therapy, a person's good arm is immobilized in thick bandages so the
bad arm must be used. Or a good leg is put in a splint, forcing greater
reliance on the bad leg. Patients practice moving the bad limb six to seven
hours every day for two to three weeks. They sweep the floor, throw balls,
draw, play checkers, or walk to the cafeteria. 

More than 150 stroke patients have been treated with this method in
Birmingham and in Germany, Dr. Taub said, and all have improved, some
regaining a great deal of movement. The improvements appear to be permanent,
he added. 

Constraint-induced movement therapy cannot work if it is given two hours a
day for three days a week for a couple of weeks, Dr. Taub said, which is what
most medical insurance plans allow. The therapy must be intensive and almost
overwhelming, he said.  

The timing of the therapy is important, said Dr. Randolph J. Nudo, the
interim director of the Kansas Center on Aging. If an animal begins using an
injured limb immediately after an experimentally induced stroke, damage to
the brain increases. That is not true in the second week after the injury,
Dr. Nudo said, so it is wise to wait several weeks before beginning
movement-based therapies. 

But Dr. Duncan said it was not clear how many people could be helped by this
technique, how many hours of therapy were needed, and how patients should be
selected. Until clinical trials involving a large number of patients have
been carried out, she said, patients should be careful not to waste their
money. 

The cost of constraint-induced therapy for a stroke patient at the University
of Alabama's new treatment center is $6,000 to $13,000, which Medicare will
not pay. Five new patients are enrolled each week, and 5,000 are on a waiting
list. 

Physicians in Birmingham and elsewhere are also offering constraint-induced
therapy to some young children with cerebral palsy who have limited movement
on one side. To help them overcome that, the children are fitted with casts
that immobilize their good limbs. 

"Kids that could not move an arm can now bat balls with that arm," Dr. Taub
said. 

In other stroke centers, a form of constraint-induced therapy - figuratively
tying down the tongue - is being tried on stroke patients who have lost some
aspects of speech. 

In the therapy, said Dr. Thomas Elbert, a neuroscientist at the University of
Konstanz in Germany, the patients play card games that force them to use the
words they tend to neglect. To prevent frustration, the game pushes each
person to perform at the top range of what he or she can do. After 10 days of
intense practice, patients who had suffered with aphasia for an average of
eight years experienced a 30 percent improvement in their verbal abilities,
he said. 

In other pilot studies in the United States and Germany, writers and
musicians with severe finger cramps have been successfully treated with
constraint-movement therapies. Because such people intensely use certain
fingers together, the borders between the brain areas devoted to those
fingers can break down. The treatment involves splints that separate the
fingers and exercises that help separate the brain areas. 

Similarly, patients with tinnitus, a ringing in the ears, suffer because of a
fusion between areas that handle different tones within primary auditory
regions of the brain. The ringing can be made to go away when patients are
exposed to many hours of different single tones. 

Patients who are partly paralyzed from spinal cord injuries are being treated
with another type of movement therapy. 

"The spinal cord is smart," said Dr. V. Reggie Edgerton, a neuroscientist at
the University of California at Los Angeles. If it is not severed, it can
relearn many aspects of locomotion. Patients are slung in harnesses over
treadmills, and therapists or automated equipment move the paralyzed legs in
natural stepping movements. Many patients have regained the ability to get
around with a walker or to walk unaided. 

In one of the strangest therapies, Dr. Paul Bach-y-Rita, a biomedical
engineer at the University of Wisconsin, has touch substitute for vision in
blind people. 

"You don't need your eyes to see," Dr. Bach-y-Rita said. "Vision is the
process whereby the brain recreates an image from a pattern of nerve pulses.
If we provide the same pattern of pulses through the skin, the brain can see,
only with less detail."  

Each blind patient wears glasses with a tiny camera that translates the
visual scene into electronic pulses, which cause vibrations in a device worn
on the tongue. 

In a recent experiment, Dr. Bach-y-Rita said, six congenitally and totally
blind people and six sighted people wearing blindfolds quickly adapted to the
tongue pulses, processing those sensory signals in the visual cortex. After
they learned to make out patterns, he said, they could recognize faces and
could hit slow-moving balls with a bat, a good example of the kind of brain
malleability that underlies many of the new rehabilitation therapies. 

http://www.nytimes.com/2001/08/28/health/anatomy/28REHA.html