• Decrease (≥50% by reference to a prospective pre-implantation run-in period) of the weekly frequency of cluster headache attacks between treatment and placebo one-month sequences. [ Time Frame: between treatment and placebo one-month sequences. ] [ Designated as safety issue: No ]
  

• Intensity of dysautomic dysfunction, acute treatment consumption, quality of life Between treatment and placebo one-month sequences. [ Time Frame: Between treatment and placebo one-month sequences. ] [ Designated as safety issue: No ]
  

Over the past 7 years, deep brain stimulation (DBS) has been used in various centres to treat patients with intractable chronic cluster headache (CH). Results in these non-controlled studies were encouraging but need to be confirmed in controlled conditions. The aim of this study is to evaluate the efficacy and safety of DBS in chronic and treatment-resistant CH, in randomized placebo-controlled conditions.

Inclusion criteria are: patients with chronic CH (>3years), with daily attack and non response to adequate treatment (verapamil up 960 mg/d, lithium with plasmatic level 0.6-1 mEq/ ml, and association of both drugs). After induction of local anaesthesia, electrodes are implanted stereotactically in the postero-inferior hypothalamus according to the previously described coordinates, and connected to a sub-cutaneous generator. In this crossover, randomized, placebo-controlled double-blinded study, the efficacy of DBS is evaluated using comparison of two one-month sequences: one with stimulation "on" and the other with stimulation "off" (considered as the placebo sequence). Primary efficacy is defined as ≥50% decrease of weekly frequency of CH attacks, compared to a prospective run-in pre-implantation period. Safety and tolerability are clinically and biologically assessed. After the randomized period, long-term efficacy and safety are evaluated after one year of stimulation in open conditions.