NEUROPSYCHOLOGICAL OUTCOME AND QUANTITATIVE NEUROIMAGING IN MILD HEAD-INJURY

Four cases of well-documented mild traumatic brain injury (Glasgow Com a scares greater than or equal to 13) in whom preinjury neuroimaging s tudies were available (three with computerized tomography and one with magnetic resonance [MR] imaging) were examined in terms of postinjury MR imaging and neuropsychological outcome. All scans were subjected t o quantitative analysis by measuring ventricular volumes and calculati ng a ventricle-to-brain ratio Since ventricular measurements provide a n index of parenchymal integrity, any systematic increase in postinjur y ventricle size would be an indication of tissue loss. In addition to using the preinjury scan for a within-subject design in comparing pos tinjury changes, similar MR measures were obtained on a group of medic al controls. Despite neuropsychological findings that suggested signif icant sequelae, quantitative postinjury MR studies did not shot; diffe rences between preinjury neuroimaging or medical control subjects. The se findings show no major anatomic abnormalities in mild TBI. Results are discussed in terms of metabolic and/or neurophysiological factors as the basis for persistent neuropsychological sequelae in most cares of mild TBI.