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(From a May 10, 2004 press release, Imperial College
London, UK)
A preliminary study has
shown for the first time that it may be possible to help people who have
suffered partial damage to their spinal cord by applying a magnetic
therapy to their brain.
Writing in this month's
Spinal Cord, a team of UK doctors describe how patients with incomplete
spinal cord injuries received repetitive transcranial magnetic stimulation
(rTMS), leading to improvements in their ability to move muscles and
limbs, and ability to feel sensations.
rTMS uses an electromagnet
placed on the scalp to generate brief magnetic pulses, about the strength
of an MRI scan, which stimulate the part of the brain called the cerebral
cortex. Incomplete spinal cord injuries are a type of spinal injury where
the spinal cord has not been entirely severed, but the patient has still
lost the ability to move or feel properly below the injury point.
Dr Nick Davey from
Imperial College London and Charing Cross Hospital, and one of the study's
authors, says: "Through rTMS we may be able to help people who have
suffered partial injuries to the spinal cord recover some of their
movement and feeling. We think it works by strengthening the information
leaving the brain through the undamaged neurons in the spinal cord. It may
work like physiotherapy but instead of repeating a physical task, the
machine activates the surviving nerves to strengthen their connections."
The researchers from
Imperial College London, the National Spinal Injuries Centre, Stoke
Mandeville Hospital, UK, and Charing Cross Hospital, UK, tested rTMS on
four patients with incomplete spinal injuries. The patients had all
sustained their injuries at least 18 months previously and had already
received conventional rehabilitation including physiotherapy. They were
all considered stable in that they were no longer undergoing natural
improvement. The patients received both real and sham rTMS treatment over
a three-week period. The rTMS treatment involved five consecutive days of
magnetic stimulation for one hour per day.
They noticed no difference
between the baseline and the sham treatment, but found that the rTMS
treatment resulted in a 37.5 (+/– 8) percent drop in intracortical
inhibition, compared with normal physiotherapy. Weaker intracortical
inhibition makes it easier for messages from the brain to pass down the
spinal cord to the rest of the body. This reduction in intracortical
inhibition was accompanied by improvement in both motor and sensory
function, which lasted for at least three weeks after the treatment.
Reduced intracortical inhibition also occurs naturally and can facilitate
functional recovery, and this is reflected in improvements to the
patients' ability to move and feel.
rTMS was a treatment
designed to treat psychiatric disorders, and has been used in treating
some of the symptoms of schizophrenia.
Dr Davey adds: "Despite
this, we still need to be extremely careful in interpreting these results
as we only sampled a small number of patients. Further studies on larger
groups of patients will need to be carried out before we will know if this
treatment is fully effective. Similarly we have no idea how long the
treatment benefits will last over a longer period."
This work was supported by
the International Spinal Research Trust, and Dr Davey and his team have
recently received a further grant, again from the International Spinal
Research Trust, to carry out further, larger trials.
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