頭部外傷慢性期における脳糖代謝の統計学的画像解析

抄録

Objective: The purpose of this study was to explore the regional cerebral metabolism in a diffuse axonal injury (DAI) group compared with normal controls and the relationship between regional cerebral metabolism and cognitive function at the chronic stage of DAI.

Methods: In 29 DAI patients, we performed 2-[18F]fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) study using statistical parametric mapping (SPM) analysis at 6 months or more after head injury. With the same protocols, thirty healthy control subjects were also studied. All DAI patients were tested with neuropsychological batteries to assess cognitive function.

Results: Between the DAI patients and normal control, group comparison showed diffuse metabolic decreases in the DAI group. Significant regional hypometabolism was found in bilateral frontal, temporal lobes, and thalamus. WAIS-R full-scale intelligent quotient (IQ) correlated positively with regional cerebral metabolism in the right cingulate gyrus and the bilateral medial frontal gyrus. In other examinations, the correlation was not provided.

Conclusion: In the DAI group, these hypometabolism may be the result of the functional cortical disconnections of the neural networks rather than of direct brain injury. Medial prefrontal cortex and anterior cingulate cortex may be an important component in supporting cognitive function following DAI, which showed diffuse cerebral metabolic reduction compared with normal controls.