[Clinical application of 18F-FDG-PET in patients with brain death]

In order to evaluate glucose metabolism in brain death, 18F-FDG-PET scans were performed in three patients with clinically highly suspected brain death. One case was caused by head trauma and other two cases were by subarachnoid hemorrhage. All of them were in deep coma without spontaneous breathing, whose intracranial pressure was remarkably elevated up to the level of mean arterial pressure. Nineteen frames of dynamic scan were started soon after intravenous injection of 18F-FDG for one minute per frame, followed by 10 minutes of static scan which started 40 minutes after the injection. Both in dynamic and static scan, no significant intracranial accumulation of 18F-FDG was seen in all of three cases. This finding can be interpreted as the evidence that there is no significant glucose utilization from blood in the brain. This is the first report of clinical application of 18F-FDG-PET to brain death. Our results support the clinical diagnosis of brain death and 18F-FDG-PET can be of value for the assessment of glucose metabolism in patients with suspected brain death.