Occipital brain perfusion deficits in children with major depressive disorder

Occipital lobe perfusion defects have been identified on regional cerebral blood flow (rCBF) SPECT scans of adolescent children and young adults with major depressive disorder (MDD). We reinvestigated a series of rCBF SPECT scans obtained several years ago on drug-naive children with a clinical diagnosis of MDD and on healthy children. Methods: To test whether visually apparent abnormalities in rCBF constitute statistically significant differences between patients, given the relatively small sample sizes, we applied the technique of statistical parametric mapping (SPM). Results: Two groups of patients were identified: 8 with significant posterior flow deficits in the occipital cortex (Brodmann's areas 18 and 19), usually symmetric, and best visualized on paramedian sagittal sections, and 13 without obvious occipital perfusion deficits but with anterior rCBF deficits in a pattern often described in the literature, attaining statistical significance in the right frontal region. Other localizations in the left frontal and bilateral prefrontal regions did not attain significance, but each localization contained statistically significant maxima (z scores). The scan findings of all 18 healthy children were normal. Conclusion: With the aid of SPM, 2 groups of children with significantly different rCBF behavior were identified. The reason for this difference is not known but should be investigated to determine its possible significance to patients with MDD.