University of Liège professor Steven Laureys‘ recent study shows that PET scans fMRI were more reliable predictors of brain injury recovery than standardized bedside assessments by doctors.
Of 126 patients in the trial, 41 were in a persistent vegetative state, 81 were in a minimally conscious state and 4 had locked-in syndrome. PET correctly predicted the extent of recovery in the following year in 74% of patients, and fMRI in 56% of patients.
A third of the patients had been previously misdiagnosed. Of 41 patients whose doctors had diagnosed a vegetative state, 13 were found by a PET scan to have some level of consciousness. Of the 13, 9 regained consciousness within the year, 3 died of other causes, and only one was still in a vegetative state.
It is not yet possible to detect hidden levels of consciousness with EEG. If developed, this would be an inexpensive way to continuously monitor patients. Because of their size and cost, fMRI and PET scans cannot provide continuous monitoring.