Science News
January 23, 2013
Oxygen Chamber Can Boost Brain
Repair Years After Stroke or Trauma
Stroke, traumatic injury, and metabolic
disorder are major causes of brain damage and permanent disabilities,
including motor dysfunction, psychological disorders, memory
loss, and more. Current therapy and rehab programs aim to help
patients heal, but they often have limited success.
Now Dr. Shai Efrati of Tel Aviv University's
Sackler Faculty of Medicine has found a way to restore a significant
amount of neurological function in brain tissue thought to be
chronically damaged -- even years after initial injury. Theorizing
that high levels of oxygen could reinvigorate dormant neurons,
Dr. Efrati and his fellow researchers, including Prof. Eshel
Ben-Jacob of TAU's School of Physics and Astronomy and the Sagol
School of Neuroscience, recruited post-stroke patients for hyperbaric
oxygen therapy (HBOT) -- sessions in high pressure chambers that
contain oxygen-rich air -- which increases oxygen levels in the
body tenfold.
Analysis of brain imaging showed significantly
increased neuronal activity after a two-month period of HBOT
treatment compared to control periods of non-treatment, reported
Dr. Efrati in PLoS ONE. Patients experienced improvements such
as a reversal of paralysis, increased sensation, and renewed
use of language. These changes can make a world of difference
in daily life, helping patients recover their independence and
complete tasks such as bathing, cooking, climbing stairs, or
reading a book.
Oxygen breathes new life into neurons
According to Dr. Efrati, there are several
degrees of brain injury. Neurons impacted by metabolic dysfunction
have the energy to stay alive, but not enough to fire electric
signals, he explains. HBOT aims to increase the supply of energy
to these cells.
The brain consumes 20 percent of the body's
oxygen, but that is only enough oxygen to operate five to ten
percent of neurons at any one time. The regeneration process
requires much more energy. The tenfold increase in oxygen levels
during HBOT treatment supplies the necessary energy for rebuilding
neuronal connections and stimulating inactive neurons to facilitate
the healing process, explains Dr. Efrati.
For their study, the researchers sought post stroke patients
whose condition was no longer improving. To assess the potential
impact of HBOT treatment, the anatomical features and functionality
of the brain were evaluated using a combination of CT scans to
identify necrotic tissue, and SPECT scans to determine the metabolic
activity level of the neurons surrounding damaged areas.
Seventy-four participants spanning 6 to
36 months post-stroke were divided into two groups. The first
treatment group received HBOT from the beginning of the study,
and the second received no treatment for two months, then received
a two-month period of HBOT treatment. Treatment consisted of
40 two-hour sessions five times weekly in high pressure chambers
containing oxygen-rich air. The results indicate that HBOT treatment
can lead to significant improvement in brain function in post
stroke patients even at chronically late stages, helping neurons
strengthen and build new connections in damaged regions.
A potential avenue for prevention
Although the study focuses on patients
only through three years post-stroke, Dr. Efrati has seen similar
improvement in patients whose brain injuries occurred up to 20
years before, belying the concept that the brain has a limited
window for growth and change. "The findings challenge the
leading paradigm since they demonstrate beyond any doubt that
neuroplasticity can still be activated for months and years after
acute brain injury, thus revealing that many aspects of the brain
remain plastic into adulthood," says Prof. Ben-Jacob.
This study also "opens the gate into
a new territory of treatment," adds Dr. Efrati. The researchers
are currently conducting a study on the benefits of HBOT for
those with traumatic brain injury. This treatment also has potential
as an anti-aging therapy, applicable in other disorders such
as Alzheimer's disease and vascular dementia at their early stages.
"It is now understood that many brain
disorders are related to inefficient energy supply to the brain,"
explains Dr. Efrati. "HBOT treatment could right such metabolic
abnormalities before the onset of full dementia, where there
is still potential for recovery."
Volume rendered Brain SPECT perfusion maps.
The results are of a patient in the treated group suffering from
left hemiparesis due to ischemic stroke that occurred 26 months
prior to inclusion in the study. The brain perfusion maps (upper
two images) show the infracted brain (deep blue color) involving
the right antero-postero-lateral frontal, right superior-parietal
and right parieto-occipital regions. Curved sagittal view in
CT MIP reconstruction of the brain shows the anatomical stroke
area (left lower image, V = posterior horn of right ventricle).
The peri-infarct region show improved perfusion as demonstrated
by HBOT image (right upper image). Quantitation of the cerebral
blood flow (CBF) change (delta between baseline and HBOT) is
demonstrated in the right lower image.
(Credit: Efrati et al. Hyperbaric Oxygen Induces Late Neuroplasticity
in Post Stroke Patients - Randomized, Prospective Trial. PLoS
ONE, 2013; DOI: 10.1371/journal.pone.0053716)
Story Source:
The above story is reprinted from materials provided by American
Friends of Tel Aviv University.
Note: Materials may be edited for content and length. For further
information, please contact the source cited above.
Journal Reference:
Shai Efrati, Gregori Fishlev, Yair Bechor, Olga Volkov, Jacob
Bergan, Kostantin Kliakhandler, Izhak Kamiager, Nachum Gal, Mony
Friedman, Eshel Ben-Jacob, Haim Golan. Hyperbaric Oxygen Induces
Late Neuroplasticity in Post Stroke Patients - Randomized, Prospective
Trial. PLoS ONE, 2013; 8 (1): e53716 DOI: 10.1371/journal.pone.0053716
Source for this article:
www.sciencedaily.com/releases/2013/01/130123144218.htm
Click here for the prntabe PDF version
Official publication
of the study in PLoS ONE
Hyperbaric
oxygen induces late neuroplasticity in Post-stroke (CVA) and
TBI patients
November 2012
Video of his conference:
Click here for Part 1
Click here for Part 2
Conclusion:
''Hyperbaric Therapy can lead
to significant
neurological improvements in post stroke and TBI patients even
at late chronic stages.''
''The observed clinical improvements
imply that neuroplasticity can still be activated long after
damage onset in regions where there is a brain SPECT/CT (anatomy/physiology)
mismatch.''
1.3 ATA with ambient air (21%
oxygen) is not a placebo:
''In many clinical trials,
1.3 is considered as placebo; this is not placebo, it increase
the oxygen in the tissue by more than 50%. This is a dose effect.''
14m20s into the
first video
About Dr. Shai Efrati:
Dr. Efrati is President of the Israel Society of Hyperbaric and
Diving Medicine (ISHDM), and is currently a senior physician
and Director of Research and Development of the Assaf
Harofeh Medical Center - Institute of Hyperbaric Medicine.
Dr. Efrati specializes in internal medicine and in hyperbaric
medicine and has many years of research experience.
Schedule of the Conference presented
in Israel in November 2012