Using functional MRI, British researchers have detected near-normal brain activity in a second patient who was believed to be in a vegetative state. Using functional MRI, British researchers have detected near-normal brain activity in a second patient who was believed to be in a vegetative state. The researchers suggest that fMRI may provide a way to identify brain activity in patients who otherwise appear to have no consciousness.

A woman made headlines last September after partially recovering after being in a vegetative state for six months after a car accident, Adrian Owen and colleagues at Britain's Cambridge University point out.

A vegetative state is more serious than a coma -- patients have reflexes, but there is no indication they are conscious. Patients in a persistent vegetative state, lasting for more than two years, have virtually no hope of recovery.

But because reflexes can be misleading, doctors often struggle to categorize and diagnose such patients.

Owen's team used fMRI to visualize the woman's brain's real-time activity, and then asked her to imagine she was playing tennis or walking through her home. To their surprise, her brain lit up, showing activity in all the sites that be would expected.

Her scans showed brain activity nearly identical to that of healthy people asked to perform the same task, Owen and colleagues report in the Archives of Neurology.

Owen said his team has scanned ten other patients, but got a response only from one, a man in his 30s in a vegetative state after a severe beating. "We put him in the scanner and we had exactly the same responses," Owen told Reuters.

Owen stressed it is important not to over-interpret the findings, although it may be possible to predict who is likely to recover. "We don't want to raise false hopes or make people think all minimally conscious patients are aware," he said.

The first patient is improving. "About six months after we scanned her, she started to show the earliest signs of improvement," he said in a telephone interview. "She is now in a minimally conscious state. She is able to produce responses occasionally but not consistently."

So far, Owen said, it appears that people are more likely to recover from brain injury after trauma than after losing consciousness because a lack oxygen -- such as in the case of Terri Schiavo, a Florida woman who spent 15 years in a persistent vegetative state and was finally allowed to die in March 2005 after a long legal battle.

The bad news is that no one yet knows how to help these patients with apparent brain activity to recover, although researchers reported this month on a patient who improved after deep-brain stimulation.

"To be perfectly honest, there is as yet no treatment or intervention that has been empirically tested and shown to be beneficial in this patient group," Owen said.


Source: Reuters

TrackBack URI for this entry

Name

Website

Title

Comment smaller | bigger

Subscribe via email (registered users only)

I have read and agree to the Terms of Usage.

Add Comment