18-FLUORODEOXYGLUCOSE POSITRON EMISSION TOMOGRAPHY IN CHILDREN AND ADOLESCENTS WITH TRAUMATIC BRAIN INJURY

Twenty-two previously normal children and adolescents who suffered a s evere, non-penetrating traumatic brain injury had PET during rehabilit ation at a median of 1.5 months after the injury. Outcome was assessed at a median of 25 months after brain injury. 16 subjects had CT or MR I within 24 days of PET and 11 subjects had a second PET at the point of outcome (median 28 months after first PET). The PET score (obtained by adding the score of 15 brain regions: normal metabolism=1; reduced =0) was significantly associated with the clinical outcome measure. PE T earlier than 12 weeks after head trauma correlated with outcome, but later PET did not. PET scores improved significantly between rehabili tation and outcome for the 11 subjects who had two PETs, but improveme nt was not associated with improvement in clinical condition. PET scor e did not add to the amount of variance explained in the last regressi on model for prediction of outcome when the results of contemporaneous CT/MRI and clinical condition were taken into account. The data sugge st that routine PET during rehabilitation is no more useful than conte mporaneous CT or MRI for prediction of outcome.