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Vegetative may need to be Redefined



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"Vegetative may need to be Redefined"
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A November 10, 2011  report, published in The Lancet, a peer reviewed medical journal that offers a special journal in Neurology, provides hope for those who are in a persistent vegetative state.  Most patients in a vegetative state have periods of wakefulness but are seemingly unresponsive to their surroundings.

It has been known for some time that some patients who appear to be totally unresponsive have some level of awareness. This is usually tested with an MRI but the cost and inaccessibility of the large MRI machines have made this difficult to study.

In a cohort study headed by Dr. Damian Cruse, PhD  of Cambridge University in England, which took place in two European centres,  16 patients who have been diagnosed as being in a vegetative state, both as a result of traumatic brain injury and non-traumatic brain injury and 12 healthy controls were tested to measure their awareness. In place of the MRI, a portable EEG machine was brought to the patients.  All of the patients were given commands to imagine movement in different parts of their body. Their responses to these commands were recorded and the results were all that they could have hoped for. Three of the sixteen vegetative patients consistently and measurably responded to the command. It didn’t appear that how the injury to the brain was received had any effect on whether or not the patients had a level of awareness.

The hope is that these results will give patients in the vegetative state a chance for a re-diagnosis.  The study seems to indicate quite clearly that even though observation may not detect any cognitive function, there are tests that can show that patients may not be in a complete vegetative state.

There was another notation by the researchers. Three of the twelve healthy volunteers did not produce a brain wave when they were given the command. This certainly gave both the researchers and doctors something to think about.  If there is no response in a healthy patient,  then no response in a vegetative patient does not necessarily mean that they are not aware.   This may lead to a whole new definition of what a vegetative state really is.

In an AP report by Malcolm Ritter,   Dr. Paul Matthews, a professor of clinical neurosciences at Imperial College in London, said in a statement that the study leaves some questions unanswered.  It's not clear whether patients who give a positive signal in one testing session will continue to do so later on, he said, nor do scientists know what a positive signal means for likelihood of a substantial recovery.

For now, more testing is necessary and the EEG, will be added to the battery of other tests that are used to determine the amount of brain activity that is found in vegetative patients.  The report however, has provided right to lifers with another reasons to fight for the rights of those who have been diagnosed as being in a persistent vegetative state.  The study seems to indicate that these and other tests are able to detect some level of awareness in over 40% of these patients.

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