title: Add-on rTMS for treatment of depression: a pilot study using stereotaxic coil-navigation according to PET data.
abstract: OBJECTIVE
  Repetitive transcranial magnetic stimulation (rTMS) is regarded as a potentially new tool to treat depression. In a double-blind, randomized, sham-controlled pilot study we investigated the efficacy of neuronavigated rTMS, guided according to the prefrontal metabolic state determined by positron emission tomography (PET).
  
  
  METHODS
  25 patients with major depression were included. Prior to rTMS, PET scans were obtained. For the real stimulation condition, the dorsolateral prefrontal cortex (DLPFC) with lower metabolic activity compared to the contralateral hemisphere was selected, if detected by prior PET. Stimulation parameters were 15 Hz, 110% motor threshold (MT), 3000 stimuli/day, for 10 days. A neuronavigational system was used to place the magnetic coil above each individuals' selected cortical region (real condition: DLPFC, sham: midline parieto-occipital, intensity 90% of MT). RTMS was administered add-on to medication. Depression-related symptoms were rated with Beck's, Hamilton's (HAM-D), and Montgomery-Asberg's (MADRS) depression rating scales.
  
  
  RESULTS
  Real stimulation improved depression according to HAM-D and MADRS moderately but significantly better compared to sham at the end of the stimulation sessions. In the real condition, four out of 13 patients responded with a mean improvement in HAM-D and/or MADRS of at least 50%, whereas none responded to sham. Antidepressant effects of stimulation of the relatively hypometabolic DLPFC were comparable to stimulation in absence of metabolic differences.
  
  
  CONCLUSIONS
  A moderate improvement of depressive symptoms after rTMS was observed. Our preliminary data show that stimulation of prefrontal hypometabolism may not be advantageous to stimulation irrespective of the metabolic state.
authors.affiliation: Department of Psychiatry, University of Ulm, Leimgrubenweg 12, D-89070 Ulm, Germany. uwe.herwig@puk.zh.ch
authors.forename: Uwe
authors.initials: U
authors.lastname: Herwig
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Lampe
authors.forename: Freimut D
authors.initials: FD
authors.lastname: Juengling
authors.forename: Arthur
authors.initials: A
authors.lastname: Wunderlich
authors.forename: Henrik
authors.initials: H
authors.lastname: Walter
authors.forename: Manfred
authors.initials: M
authors.lastname: Spitzer
authors.forename: Carlos
authors.initials: C
authors.lastname: Schönfeldt-Lecuona
mesh_terms: D000328:Adult; D003866:Depressive Disorder / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy*; D004311:Double-Blind Method; D004558:Electric Stimulation / Q000379:methods; D004574:Electromagnetic Fields; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017397:Prefrontal Cortex / Q000000981:diagnostic imaging / Q000503:physiopathology*; D011569:Psychiatric Status Rating Scales; D012720:Severity of Illness Index; D014055:Tomography, Emission-Computed; D016896:Treatment Outcome