[The clinical utility of MR diffusion tensor imaging and spatially normalized PET to evaluate traumatic brain injury patients with memory and cognitive impairments].

We detected and compared abnormal brain areas using both MR diffusion tensor imaging (DTI) and easy Z score imaging system (eZIS) of FDG-PET for traumatic brain injury patients with memory and cognitive impairments. Twenty normal subjects and eighteen diffuse axonal injury patients with memory and cognitive impairments were studied with DTI and eZIS of 18F-FDG-PET. DTI contained fractional anisotorophy (FA) analysis and the tractography for the corpus callosum. After PET imaging was performed, statistical analysis using eZIS was undergone with followed processing steps, including smoothing, normalization and z transformation with respect to normal database. Z score map was superimposed on 3D MRI brain. Group analysis was performed using SPM. In diffuse axonal injury patients, the decline of FA was observed around the corpus callosum in comparison with normal subjects and the reduction of glucose metabolism was shown in the cingulated association. These results suggest that the reduction of metabolism within the cingulated cortex indicated deprived neuronal activation caused by the impaired neuronal connectivity that was revealed with DTI. Furthermore, the metabolic abnormalities within the cingulated cortex may be responsible for memory and cognitive impairments. DTI and spatially normalized PET have a role in neuroimaging interpretation for patients with memory and cognition impairments because its 3D better visualization allows objective and systematic investigation.