PET Scans may Spot Potential of Coma Recovery

A recent study takes an in-depth look into identifying comatose patients who may carry a potential for recovery.

As many tests typically used to assess a patient's level of comatose severity may not accurately show symptoms of recovery, with up to 40 percent of patients misdiagnosed through certain testing methods, findings show that PET scans could spot the signs of recovery. 

Belgian researchers examined 122 patients with brain injuries, 41 of whom suffered severe brain damage that lead to a vegetative state. Unfortunately, for those suffering from vegetative conditions for over a year, there is little to no chance of recovery. The other 81 patients in the study were considered minimally conscious as they showed some signs of responsiveness and awareness. These patients are considered to have better hopes of potential recovery and survival.

For the experiment, patients underwent two types of scans--PET, which involved the imaging agent Fluorodeoxyglucose and a functional MRI scan that tracks the brains activity in real time.

The researchers observed minimal levels of consciousness in 13 of the patients in the vegetative state. However, nine of them also progressed into a minimally conscious state a year following that means they exhibited levels of consciousness at the same level of fully conscious individuals.

Though PET scans are typically better at identifying conscious and unconscious patients, findings showed that a third of the subjects who were diagnosed as behaviorally unresponsive using bedside tests were found to have some kind of consciousness when assessed with the PET scans.

"Cerebral I8F-FDG PET could be used to complement bedside examinations and predict long-term recovery of patients with unresponsive wakefulness syndrome," the researchers said, via a press release. "Active fMRI might also be useful for differential diagnosis, but seems to be less accurate."

More information regarding the findings can be seen via The Lancet.