RESUMO
Objective : The objective of the present study was to clarify the differences in statistical imaging analysis of functional and morphologic imaging between neuropsychological impairments (NPI) and nonorganic mental disorder (MD) after traumatic head injury. Methods : Six depressive patients after head injury without abnormal findings on conventional MRI (MD group), six nondepressive patients with NPI after diffuse axonal injury (NPI group), and six healthy subjects with a history of head injury (control group) were enrolled in this study. For all subjects, <sup>99m</sup>Tc-ethylcysteinate dimmer (Tc-ECD) SPECT and MRI 3D volumetry were performed. Imaging data were analyzed using statistical parametric mapping, and then, the analyzed data were compared among the three groups (2 sample t test, uncorrected <i>p</i><0.01). Results : Compared to the Control group, significant low Tc-ECD uptake and regional grey matter volume reduction were noticed bilaterally in the anterior medial brain aspects such as the anterior cingulate cortex in both the MD group and the NPI group. These findings were significantly greater in the NPI group than in the MD group. Moreover, these functional and morphologic abnormalities were also spread to more medial and deep aspects such as the posterior limbic and the brain stem in the NPI group. Conversely, in the MD group without morphologic abnormalities, only functional abnormalities spread above the common lesions to the dorsolateral brain aspects such as the superior frontal lobe. Conclusion : Our results revealed some characteristics of statistical imaging analysis in functional and morphologic imaging of MD and NPI patients after head injury. These findings seem to be novel and can serve as useful information for future investigation of neural correlates with both NPI and MD after head injury.