SPECT brain imaging abnormalities in attention deficit hyperactivity disorder.

SPECT using N-Isopropyl I-123 IMP was performed, as part of a neuropsychiatric evaluation, on 10 patients with the DSM III-R diagnosis of Attention Deficit Hyperactivity Disorder (ADHD) and 6 patients from a non-ADHD mixed psychiatric group used as controls for comparison. Mean regional I-123 IMP SPECT region of interest (ROI) count ratios (left to right) demonstrated that the ADHD patients had greater overall hemispheric I-123 IMP uptake asymmetry with less activity in the left frontal and left parietal regions in comparison to control patients. Both groups demonstrated similar I-123 IMP uptake asymmetry in the temporal regions. These findings are consistent with previous studies of brain physiology in ADHD implicating regional cortical perfusion and metabolism abnormalities in areas which are involved in the control of attentional processes.