PET imaging of brain glucose metabolismSTENDERS ET AL.Differentiating states of consciousness in brain-injured patients is a major challenge for clinicians. Researchers from the University of Copenhagen, Denmark, and their colleagues recently used positron emission tomography (PET) to measure the metabolism of glucose in the brains of 131 patients, finding that 42 percent of normal cortical function is the minimum amount of energy required for conscious awareness. The findings provide “a simple and objective metabolic marker” of consciousness, the authors wrote in their study, published today (May 26) in Current Biology.
“[The study authors] distinguished a strong physical measurement of two different states of lowered consciousness beautifully, with excellent data,” Robert Shulman of Yale University, who reviewed the study, told The Scientist. “They did this by measuring the cerebral metabolic rate of glucose consumption using PET, [which is] a strong, reliable measurement,” he added.
Previous studies have shown that brain glucose metabolism declines when consciousness is lost, but researchers did not have a quantitative measure for distinguishing between disorders of consciousness—such as coma, minimally conscious state (MCS), and the more severe unresponsive wakefulness syndrome (UWS). Ron Kupers of the University of Copenhagen and colleagues last year showed that MCS and UWS are associated with brain metabolic levels that are approximately half those of healthy adults in ...
