U.S. stroke victims train brains to see again
Thu
Feb 8, 2007 4:00pm ET
By Julie Steenhuysen
CHICAGO, Feb 8 (Reuters) - A new
study bolsters evidence that people partially blinded by a stroke or brain
injury may be able to improve their field of vision by teaching new parts of
their brain to see, U.S.
researchers said on Thursday.
Using a computer workout program for
the brain, about three-quarters of patients in the study could see better after
six months of treatment with the therapy, which trains neighboring brain cells
to take over for damaged areas.
The therapy, which is marketed by
NovaVision of Boca Raton, Florida and won U.S. Food and Drug Administration
approval in 2003, is controversial among neurologists because it challenges the
widely held belief that vision lost through brain injury or stroke can't be
treated.
A German study published in the
British Journal of Ophthalmology in 2005 pronounced the therapy a flop.
But NovaVision says the latest
study, conducted on patients in the last two years and whose results were
presented at the International Stroke Conference in San Francisco on Thursday, reinforces its
contention that the treatment works.
NovaVision says the results of the
therapy proved the brain is plastic, capable of rewiring itself even long after
an injury. The idea of "neuroplasticity" has been used to help stroke
patients recover lost speech and movement but vision had been thought to be
immutable.
"It makes no sense to believe
there is no plasticity in the visual cortex," said Dr. Jose Romano, a
neurologist at the University
of Miami who conducted
the study and serves on NovaVision's scientific advisory board
Vision restoration therapy could
help the 1.5 million stroke or brain injury victims in the United States who have visual
defects that make everyday tasks like reading and watching television a
challenge, the company says.
SEEING MORE
Romano and colleagues evaluated 161
patients who underwent treatment at 16 U.S. research centers for six
months.
Using a special laptop and attached
chin rest, patients stared at a fixed dot while various lights flashed along
the border of their blind spot. They clicked a computer mouse each time they
could detect the flash of light.
After
six months of twice daily therapy, 76 percent of patients were helped,
regaining on average 5 degrees of their visual field, Romano said in an interview
with Reuters.
That is roughly the equivalent of a
hand held at arm's length, then moved five inches to the right or left.
"It allows you to read and to not bump into things," Romano said.
Stroke researcher Randolf Marshall
of Columbia University
Medical Center
in New York,
who has used the therapy in his own practice, examined six patients before and
after one month of therapy using functional magnetic resonance imaging or fMRI.
Marshall, who has no ties to
NovaVision, found that all six showed increased activity in the area of the
brain bordering the injury.
"The brain has essentially
learned to use more of its activity ... in this particular trained location. We
are really looking at a pattern of learning," he said.
Last month, NovaVision raised $20
million in its third round of financing, snagging Johnson & Johnson (JNJ.N:
Quote, Profile
, Research)
as one of its investors. The $6,000 treatment is not covered by most insurance,
but the company is seeking reimbursement under the U.S. government's Medicare health
program for the elderly.
Ellie Kline
Vice President
Healthcare Media Relations
Edelman
1500 Broadway, 26 Floor
New York, NY 10036
Ph. 212-704-4528
F. 212-921-1143
C. 917-584-7961
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