Aggressive behavior and mood disorders frequently appear in childhood. There is often lack of objective data to support a specific clinical diagnosis. Ultimately it is likely that alterations in production, concentration, storage, release, reuptake and degradation of neurotransmitters such as serotonin, dopamine, acetylcholine and gamma-aminobutyric acid play key roles in the manifestations of mood disorders. We sought to determine if more gross anatomic patterns of regional brain activation in a "baseline" state might also supply an objective means of verifying the presence of a mood disorder characterized by anger or aggressive behavior.
We studied 8 patients, 3 girls and 5 boys, ages ranging from 6 to 12, referred for SPECT brain imaging with the diagnosis of an attention deficit disorder or autism. All had been reported as having temper problems on the routine questionnaire completed by the parents prior to SPECT imaging. The patients, who were not sedated, had absolute cerebral blood flow measured by the xenon 133 gas inhalation technique followed by intravenous injection of Tc-99m HMPAO with an administered dose calculated according to patient age and weight. One hour following the injection, high resolution brain SPECT imaging was performed using a Picker triple headed camera with fan beam collimators.
We analyzed the brain SPECT studies using 3D volume rendered semi-transparent images with dual cut off windows of 88% (high) and 60-65% (lower value depending on the patient absolute mean cortical blood flow), as well as the traditional transverse, coronal and sagittal sections. The dual window 3D display helped demonstrate increased perfusion or activation of either or both right and left temporal lobes in all 8 of the patients. This pattern was not seen in children with similar clinical diagnoses but whose parents did not report temper problems. These preliminary findings support the proposition that an increase in perfusion to the temporal lobes may be associated with oppositional or aggressive behavior. They suggest that Brain SPECT with images displayed to emphasize the presence of regions of increased blood flow may be useful in objectively confirming the presence of mood disorders and perhaps in guiding appropriate therapy.
Key words: SPECT, aggression, children, behavior, mood disorders, increased regional cerebral blood flow
