title: Structural Gray Matter Alterations in Chronic Migraine: Implications for a Progressive Disease?
abstract: OBJECTIVE
  To identify possible gray matter alterations in patients with chronic migraine using voxel-based morphometry (VBM).
  
  
  BACKGROUND
  VBM studies demonstrate structural alterations of gray matter (GM) in episodic migraine (EM) patients. Some of these alterations correlate with disease duration and headache frequency. We assessed GM alterations in chronic migraine (CM) and EM to evaluate the concept of migraine as a progressive disorder of the brain.
  
  
  METHODS
  Individually age and sex-matched subjects with CM or EM (both without aura) and healthy controls (n = 21 per group) underwent magnetic resonance imaging-based VBM.
  
  
  RESULTS
  We found an increase of GM volume (GMV) in amygdala and putamen, in CM compared to controls. GMV of EM compared to controls did not differ statistically significantly. Headache frequency in all migraineurs (EM and CM) correlated positively with GMV in putamen, frontal and temporal gyrus and negatively in left cuneus.
  
  
  CONCLUSIONS
  CM is associated with structural changes in brain regions involved in pain processing but also in affective and cognitive aspects of pain. Some GM alterations are correlated with headache frequency assessed in EM and CM. The findings support the assumption that chronic pain alters brain plasticity. GMV increase may reflect a remodeling of the central nervous system due to repetitive headache attacks leading to chronic sensitization and a continuous ictal-like state of the brain in chronic migraineurs.
authors.affiliation: Department of Neurology, Charité Universitätsmedizin Berlin, Berlin, Germany.|Center for Stroke Research Berlin (CSB), Charité Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Lars
authors.initials: L
authors.lastname: Neeb
authors.affiliation: Department of Neurology, Charité Universitätsmedizin Berlin, Berlin, Germany.|Center for Stroke Research Berlin (CSB), Charité Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Kaili
authors.initials: K
authors.lastname: Bastian
authors.affiliation: Center for Stroke Research Berlin (CSB), Charité Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Kersten
authors.initials: K
authors.lastname: Villringer
authors.affiliation: Department of Neurology, Charité Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Heike
authors.initials: H
authors.lastname: Israel
authors.affiliation: Department of Neurology, Charité Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Uwe
authors.initials: U
authors.lastname: Reuter
authors.affiliation: Center for Stroke Research Berlin (CSB), Charité Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Jochen B
authors.initials: JB
authors.lastname: Fiebach
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001921:Brain / Q000000981:diagnostic imaging*; D016022:Case-Control Studies; D002908:Chronic Disease; D018450:Disease Progression; D005260:Female; D066128:Gray Matter / Q000000981:diagnostic imaging* / Q000473:pathology*; D006801:Humans; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D008881:Migraine Disorders / Q000000981:diagnostic imaging*; D012720:Severity of Illness Index
keywords: chronic migraine; magnetic resonance imaging; migraine; pain processing; progression; voxel-based morphometry