Deep Brain Stimulation (DBS) of the Globus Pallidus (GP) in Huntington's Disease (HD)

Inclusion Criteria: * Clinically symptomatic and genetically confirmed HD (number of CAG repeats ≥ 36) * Age ≥18 years * Moderate stage of the disease (UHDRS motor score ≥ 30) * Chorea despite best medical treatment (UHDRS chorea subscore ≥ 10) * Mattis Dementia Rating Scale ≥ 120 (or \> 80% of items testable independently from motor impairment) * Patient has stable medication prior six weeks before inclusion * Signed informed consent Exclusion Criteria: * Juvenile HD (Westphal variant) or predominant bradykinesia * Postural instability with UHDRS retropulsion score \> 2 * Severe comorbidity compromising operability and/or life expectancy and/or quality of life during the trial duration (e.g. cancer with life expectancy \< 6 months, NYHA 3 and 4 rising the anaesthetic risk according to the anaesthesiologist) * Acute suicidality * Acute psychosis (symptoms within previous 6 months) * Participation in any interventional clinical trial within 2 months before screening * Cortical atrophy grade 3 * Patients with risk of coagulopathies and/or increased risk of haemorrhage * Patients with an implanted pacemaker or defibrillator * Pregnancy * lactation