title: Orbitofrontal cortex volumes in medication naïve children with major depressive disorder: a magnetic resonance imaging study.
abstract: OBJECTIVE
  Adults with major depressive disorder (MDD) are reported to have reduced orbitofrontal cortex (OFC) volumes, which could be related to decreased neuronal density. We conducted a study on medication naïve children with MDD to determine whether abnormalities of OFC are present early in the illness course.
  
  
  METHODS
  Twenty seven medication naïve pediatric Diagnostic and Statistical Manual of Mental Disorders, 4(th) edition (DSM-IV) MDD patients (mean age +/- SD = 14.4 +/- 2.2 years; 10 males) and 26 healthy controls (mean age +/- SD = 14.4 +/- 2.4 years; 12 males) underwent a 1.5T magnetic resonance imaging (MRI) with 3D spoiled gradient recalled acquisition. The OFC volumes were compared using analysis of covariance with age, gender, and total brain volume as covariates.
  
  
  RESULTS
  There was no significant difference in either total OFC volume or total gray matter OFC volume between MDD patients and healthy controls. Exploratory analysis revealed that patients had unexpectedly larger total right lateral (F = 4.2, df = 1, 48, p = 0.05) and right lateral gray matter (F = 4.6, df = 1, 48, p = 0.04) OFC volumes compared to healthy controls, but this finding was not significant following statistical correction for multiple comparisons. No other OFC subregions showed a significant difference.
  
  
  CONCLUSIONS
  The lack of OFC volume abnormalities in pediatric MDD patients suggests the abnormalities previously reported for adults may develop later in life as a result of neural cell loss.
authors.affiliation: Department of Radiology, The University of Cincinnati, Cincinnati, Ohio, USA.
authors.forename: Hua-Hsuan
authors.initials: HH
authors.lastname: Chen
authors.forename: David R
authors.initials: DR
authors.lastname: Rosenberg
authors.forename: Frank P
authors.initials: FP
authors.lastname: MacMaster
authors.forename: Philip C
authors.initials: PC
authors.lastname: Easter
authors.forename: Sheila C
authors.initials: SC
authors.lastname: Caetano
authors.forename: Mark
authors.initials: M
authors.lastname: Nicoletti
authors.forename: John P
authors.initials: JP
authors.lastname: Hatch
authors.forename: Fabiano G
authors.initials: FG
authors.lastname: Nery
authors.forename: Jair C
authors.initials: JC
authors.lastname: Soares
mesh_terms: D000293:Adolescent; D000704:Analysis of Variance; D001931:Brain Mapping; D003865:Major Depressive Disorder / Q000473:pathology*; D005260:Female; D005625:Frontal Lobe / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male