title: Decreased gray matter volume of the medial orbitofrontal cortex in panic disorder with agoraphobia: a preliminary study.
abstract: BACKGROUND
  Patients with panic disorder with agoraphobia (PDA) have clinical symptoms such as the fear of being outside or of open spaces from which escape would be difficult. Although recent neurobiological studies have suggested that fear conditioning and extinction are associated with PDA, no study has examined the possible structural abnormalities in patients with PDA.
  
  
  METHODS
  This preliminary study compares the gray matter volume among patients with PDA, those with panic disorder without agoraphobia (PDW), and healthy controls (HC) using high-resolution 3.0 T magnetic resonance imaging (MRI) with voxel-based morphometry (VBM).
  
  
  RESULTS
  Compared with HC, patients with PDA showed decreased gray matter volume in their left medial orbitofrontal gyrus. However, differences were not found in the gray matter volumes of patients with PDW and whole panic disorder compared with HC.
  
  
  CONCLUSIONS
  These findings suggest that the phobic avoidance found in patients with PDA arise from abnormalities in the medial orbitofrontal cortex, which plays an important role in fear extinction. Future studies should investigate the neuroanatomical substrates of PDA and distinguish them from those of PDW.
authors.affiliation: Department of Psychiatry, Soonchunhyang University Bucheon Hospital, Bucheon, Republic of Korea.
authors.forename: Kyoung-Sae
authors.initials: KS
authors.lastname: Na
authors.forename: Byung-Joo
authors.initials: BJ
authors.lastname: Ham
authors.forename: Min-Soo
authors.initials: MS
authors.lastname: Lee
authors.forename: Leen
authors.initials: L
authors.lastname: Kim
authors.forename: Yong-Ku
authors.initials: YK
authors.lastname: Kim
authors.forename: Heon-Jeong
authors.initials: HJ
authors.lastname: Lee
authors.forename: Ho-Kyoung
authors.initials: HK
authors.lastname: Yoon
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000379:Agoraphobia / Q000150:complications / Q000473:pathology*; D001284:Atrophy / Q000473:pathology; D016022:Case-Control Studies; D005260:Female; D005625:Frontal Lobe / Q000473:pathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D036421:Nerve Fibers, Unmyelinated / Q000473:pathology*; D059906:Neuroimaging; D016584:Panic Disorder / Q000150:complications / Q000473:pathology*
keywords: ANOVA; API; ASI-R; Acute Panic Inventory; Agoraphobia; Analysis of Variance; Anxiety Severity Index, revised version; DARTEL; DMN; DSM-IV; Default Mode Network; Diagnostic and Statistical Manual for Mental Disorders, Fourth edition; Diffeomorphic Anatomical Registration using Exponentiated Lie Algebra; FWE; Family-Wise Error; Gray matter; HC; Healthy Controls; MINI; MNI; MP-RAGE; MRI; Magnetic Resonance Imaging; Magnetization Prepared Rapid Acquisition Gradient Echo; Mini-International Neuropsychiatric Interview; Montreal Neurological Institute; PD; PDA; PDSS; PDW; Panic Disorder; Panic Disorder Severity Scale; Panic Disorder with Agoraphobia; Panic Disorder without Agoraphobia; Panic disorder; Prefrontal cortex; ROIs; Regions of Interest; SPSS; STAI; Spielberger State-Trait Anxiety Inventory; Statistical Package for the Social Sciences; TIV; Total Intracranial Volume; VBM; Voxel-Based Morphometry; Voxel-based morphometry; fMRI; functional Magnetic Resonance Imaging (fMRI)