April 16, 2014

expert reaction to brain imaging and vegetative states

Researchers publishing in The Lancet reported using positron emission tomography (PET), a brain imaging technique, in clinical practice to determine which severely brain damaged individuals in vegetative states have the potential to recover consciousness.

Prof Martin Monti, Departments of Psychology and Neurosurgery at University of California, Los Angeles (UCLA), said:

“This new report marks a long-awaited first step towards translating cutting-edge science into clinical practice. In the last 5 to 8 years, thanks to neuroimaging techniques, we have taken giant strides towards understanding brain function at the lower boundaries of consciousness. However, with the exception of a handful of studies, it has mostly been high-impact proofs of principle based on few cases. While revolutionizing our scientific understanding of the vegetative state, these cases also created significant difficulties in clinical practice. Doctors were left having to explain to families why not all vegetative state patients undergo fMRI scanning, and families might have been led to believe that if only their loved one could undergo an fMRI scan it would certainly reveal that they are still conscious. Now, large numbers at hand, we are getting a fuller picture of how neuroimaging techniques can best contribute to clinical practice, and we can start turning scientific revolutions into even better medical care.”

Dr Michael Bloomfield, Clinical Research Fellow, Medical Research Council Clinical Sciences Centre, London, said:

“This really exciting study suggests for the first time that a brain scanning technique called PET could be used in the future to predict the likelihood that a patient may ‘wake-up’ a long time after a severe brain injury.  However, much more research is needed to work out how accurate PET scans might be at doing this and make the technique reliable enough to be potentially used in specialist centres.

“If the results of this study are confirmed in future research, this could have far-reaching clinical, ethical and legal implications, including whether to offer an apparently unconscious patient pain relief and, ultimately, whether treatments that may be keeping someone alive should be continued or not.

“I think there may be a revolution on the horizon in terms of using PET scans to help doctors and patients make decisions about which treatments may be most helpful in a variety of medical conditions.  For example, our own research at the MRC Clinical Sciences Centre is investigating whether PET scans can predict the severity of mental illnesses and whether PET scans are helpful in predicting which treatments might be most useful in helping people recover from mental health problems.”

‘Diagnostic precision of PET imaging and functional MRI in disorders of consciousness: a clinical validation study’ by Stender et al. published in The Lancet on Wednesday 16th April.