title: Occipital nerve stimulation in medically intractable, chronic cluster headache. The ICON study: rationale and protocol of a randomised trial.
abstract: BACKGROUND
  About 10% of cluster headache patients have the chronic form. At least 10% of this chronic group is intractable to or cannot tolerate medical treatment. Open pilot studies suggest that occipital nerve stimulation (ONS) might offer effective prevention in these patients. Controlled neuromodulation studies in treatments inducing paraesthesias have a general problem in blinding. We have introduced a new design in pain neuromodulation by which we think we can overcome this problem.
  
  
  METHODS
  We propose a prospective, randomised, double-blind, parallel-group international clinical study in medically intractable, chronic cluster headache patients of high- versus low-amplitude ONS. Primary outcome measure is the mean number of attacks over the last four weeks. After a study period of six months there is an open extension phase of six months. Alongside the randomised trial an economic evaluation study is performed.
  
  
  CONCLUSIONS
  The ICON study will show if ONS is an effective preventive therapy for patients suffering medically intractable chronic cluster headache and if there is a difference between high- and low-amplitude stimulation. The innovative design of the study will, for the first time, assess efficacy of ONS in a blinded way.
authors.affiliation: Department of Neurology, LUMC, the Netherlands.
authors.forename: Leopoldine A
authors.initials: LA
authors.lastname: Wilbrink
authors.forename: Onno P M
authors.initials: OP
authors.lastname: Teernstra
authors.forename: Joost
authors.initials: J
authors.lastname: Haan
authors.forename: Erik W
authors.initials: EW
authors.lastname: van Zwet
authors.forename: Silvia M A A
authors.initials: SM
authors.lastname: Evers
authors.forename: Geert H
authors.initials: GH
authors.lastname: Spincemaille
authors.forename: Peter H
authors.initials: PH
authors.lastname: Veltink
authors.forename: Wim
authors.initials: W
authors.lastname: Mulleners
authors.forename: Ronald
authors.initials: R
authors.lastname: Brand
authors.forename: Frank J P M
authors.initials: FJ
authors.lastname: Huygen
authors.forename: Rigmor H
authors.initials: RH
authors.lastname: Jensen
authors.forename: Koen
authors.initials: K
authors.lastname: Paemeleire
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Goadsby
authors.forename: Veerle
authors.initials: V
authors.lastname: Visser-Vandewalle
authors.forename: Michel D
authors.initials: MD
authors.lastname: Ferrari
mesh_terms: D002985:Clinical Protocols; D003027:Cluster Headache / Q000628:therapy*; D004311:Double-Blind Method; D004599:Electric Stimulation Therapy / Q000379:methods*; D004567:Electrodes, Implanted; D006801:Humans; D012107:Research Design; D012886:Skull / Q000294:innervation
keywords: Cluster headache; ICON study; chronic cluster headache; occipital nerve stimulation; study protocol