title: Immediate cerebral metabolic changes induced by discontinuation of deep brain stimulation of subcallosal cingulate gyrus in treatment-resistant depression.
abstract: BACKGROUND
  Positron emission tomography (PET) studies have shown that the antidepressant effect of chronic deep brain stimulation (DBS) of the subcallosal cingulate gyrus (SCG) may be consequence of modifications of brain metabolism at key structures involved in depression. Like clinical benefits, these metabolic changes may reverse when the stimulation is discontinued, even preceding clinical worsening. However no data on immediate effects of DBS discontinuation are available. The aim of this study was to determine immediate cerebral metabolism changes during a short switch-off of electrical stimulation in implanted patients with treatment-resistant depression (TRD) who had achieved clinical improvement after a period of chronic DBS.
  
  
  METHODS
  Seven patients with TRD who had been previously implanted for DBS in SCG were included. After a period of clinical stabilization two consecutive FDG-PET were acquired, the first with active stimulation and the second after 48 h of inactive stimulation. A HAMD-17 to assess depressive symptoms was performed before both scans. Analyses were performed with SnPM8.
  
  
  RESULTS
  Inactive stimulation was characterized by metabolism decreases in dorsal anterior cingulate (Broadmann Area, BA24), premotor region (BA6) and putamen with respect to active stimulation. No clinical changes according to HAMD-17 were detected.
  
  
  CONCLUSIONS
  The main limitation of this study is the small sample size.
  
  
  CONCLUSIONS
  Our results point to immediate effects of DBS discontinuation on metabolism of brain depressive network which precede clinical changes, helping to disentangle the rationale behind DBS efficacy in TRD.
authors.affiliation: Department of Psychiatry, Hospital de la Santa Creu i Sant Pau, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Institut d׳Investigació Biomèdica Sant Pau (IIB-Sant Pau), Universitat Autònoma de Barcelona (UAB), Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: Martín-Blanco
authors.affiliation: Department of Psychiatry, Hospital de la Santa Creu i Sant Pau, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Institut d׳Investigació Biomèdica Sant Pau (IIB-Sant Pau), Universitat Autònoma de Barcelona (UAB), Spain.
authors.forename: Maria
authors.initials: M
authors.lastname: Serra-Blasco
authors.affiliation: Department of Psychiatry, Hospital Nostra Senyora de Meritxell, Andorra.
authors.forename: Rosario
authors.initials: R
authors.lastname: Pérez-Egea
authors.affiliation: Department of Psychiatry, Hospital de la Santa Creu i Sant Pau, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Institut d׳Investigació Biomèdica Sant Pau (IIB-Sant Pau), Universitat Autònoma de Barcelona (UAB), Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: de Diego-Adeliño
authors.affiliation: Department of Psychiatry, Hospital de la Santa Creu i Sant Pau, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Institut d׳Investigació Biomèdica Sant Pau (IIB-Sant Pau), Universitat Autònoma de Barcelona (UAB), Spain.
authors.forename: Mar
authors.initials: M
authors.lastname: Carceller-Sindreu
authors.affiliation: Department of Psychiatry, Hospital de la Santa Creu i Sant Pau, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Institut d׳Investigació Biomèdica Sant Pau (IIB-Sant Pau), Universitat Autònoma de Barcelona (UAB), Spain.
authors.forename: Dolors
authors.initials: D
authors.lastname: Puigdemont
authors.affiliation: Department of Neurosurgery, Hospital de la Santa Creu i Sant Pau, Institut d'Investigació Biomèdica Sant Pau (IIB-Sant Pau), Universitat Autònoma de Barcelona (UAB), Spain.
authors.forename: Joan
authors.initials: J
authors.lastname: Molet
authors.affiliation: Department of Psychiatry, Hospital de la Santa Creu i Sant Pau, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Institut d׳Investigació Biomèdica Sant Pau (IIB-Sant Pau), Universitat Autònoma de Barcelona (UAB), Spain.
authors.forename: Enric
authors.initials: E
authors.lastname: Álvarez
authors.affiliation: Department of Psychiatry, Hospital del Mar, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Universitat Autònoma de Barcelona (UAB), Spain.
authors.forename: Víctor
authors.initials: V
authors.lastname: Pérez
authors.affiliation: Department of Psychiatry, Hospital de la Santa Creu i Sant Pau, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Institut d׳Investigació Biomèdica Sant Pau (IIB-Sant Pau), Universitat Autònoma de Barcelona (UAB), Spain. Electronic address: mportella@santpau.cat.
authors.forename: Maria J
authors.initials: MJ
authors.lastname: Portella
mesh_terms: D000328:Adult; D002540:Cerebral Cortex / Q000000981:diagnostic imaging / Q000378:metabolism*; D046690:Deep Brain Stimulation; D061218:Depressive Disorder, Treatment-Resistant / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000628:therapy; D005260:Female; D006179:Gyrus Cinguli / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011877:Radionuclide Imaging; D016896:Treatment Outcome; D028761:Withholding Treatment
keywords: Deep brain stimulation; Positron emission tomography; Treatment-resistant depression