Study of Sequentially Applied Repetitive Transcranial Magnetic Stimulation in Obsessive- Compulsive Disorders
Condition: Obsessive-compulsive Disorder
MeSH terms: Compulsive Personality Disorder; Obsessive-Compulsive Disorder
Study type: Interventional

Summary: 
      The purpose of study was to investigate possible therapeutic effects and safety of
      sequentially combined low-frequency repetitive transcranial magnetic stimulation (rTMS) to
      the right dorsolateral prefrontal cortex (DLPFC) and supplementary motor area (SMA) in
      patients with treatment-resistant obsessive-compulsive disorder (OCD).
    

Detailed description: 
      Obsessive-compulsive disorder (OCD) is a relatively common psychiatric disorder characterized
      by repetitive, intrusive thoughts and time-consuming behavioral or mental acts. Many OCD
      patients who do not respond to conventional treatments experience severe distress and
      disruptions in their daily activities. Novel approaches including psychopharmacological
      therapy and surgical techniques for treatment-resistant OCD have been proposed. With recent
      advances in non-invasive technique for stimulating the cerebral cortex, repetitive
      transcranial magnetic stimulation (rTMS) has been proposed as a potential therapeutic
      approach for various psychiatric illnesses including OCD.

      Because of contradictory findings and a lack of controlled trials in OCD, rTMS cannot be yet
      recommended as routine therapy for OCD. However, it may have a potential clinical effect as a
      putative add-on treatment for OCD and an alternative therapy for treatment-resistant OCD.

      For useful clinical applications, it is very important to develop methods to enhance the
      efficacy of rTMS. There are a number of putative ways to do this, and one of them is
      sequentially combining two forms of stimulation which are considered to have potential
      therapeutic effects. More recently, the sequential application of two stimulation regimens
      (high-frequency left-side rTMS and low-frequency right-side rTMS to the prefrontal cortex)
      has been found to have a substantial therapeutic effect in patients with treatment-resistant
      major depression. Therefore, the investigation for a sequentially combining effect of both
      the right prefrontal and the SMA stimulation would be worthwhile in OCD patients.
    

Intervention name(s): repetitive transcranial magnetic stimulation (Magstim rapid magnetic stimulator)
Intervention type(s): Device
Intervention description(s): For the active group, rTMS over the right prefrontal cortex and the SMA was sequentially performed. The rTMS of the right dorsolateral prefrontal cortex was conducted at a point 5 cm anterior to the point at which the MT was determined, and it was administered at an intensity of 110% of the RMT, a frequency of 1 Hz, for 10 minutes, and with an inter-train interval of 2 minutes (1200 stimuli/d).
The vertex (Cz) was measured for each patient, and the SMA was defined at 15% of the distance between the inion and nasion anterior to Cz on the sagittal midline, according to the international 10-20 EEG system. The rTMS over the SMA was administered at an intensity of 100% of the RMT, a frequency of 1 Hz, for 10 minutes and with an inter-train interval of 2 minutes (1200 stimuli/d).
For the sham group, the sham stimulation was applied with the coil angled at 45° from the scalp using the same parameters as the active stimulation group over the same area.
Other intervention name(s): A Magstim rapid magnetic stimulator with a 70-mm figure-of-eight coil (Magstim Company Ltd, Whitland, UK) was used for treatment.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: obsessive-compulsive disorder; repetitive transcranial magnetic stimulation; right dorsolateral prefrontal cortex; supplementary motor area (SMA)