The relations between location and outcome in stereotactic neurosurgery for drug abuse

INTERVENTION: 1. Radiofrequency ablation of the NAc 2. Different lesioning location and volumn within NAc in four groups 3. Abstinence from opioid use and adverse events related to operation 4. Neuropsychiatric functional changes, measured by formal neuropsychiatric instruments Follow up length: 4 years CONDITION: Functional neurosurgery for drug addiction ; Surgery ; Functional neurosurgery PRIMARY OUTCOME: Abstinence from opioid use, measured by morphine urinalysis and naloxone testing in the fourth post‐operative year SECONDARY OUTCOME: 1. Complications in stereoctactic surgery (e.g fever, nausea/emesis, seizure, infection, intracranial haemorrhages); 2. Possible neuropsychiatric change related to NAc ablation: memory, motivation, emotion, olfactory sensation; ; After operation, the secondary outcomes were measured at six month intervals and extended for four years. INCLUSION CRITERIA: 1. Heroin abuse using 0.3 ‐ 1.0 g daily for at least 3 years by intravenous injection with or without concomitant nasal inhalation 2. Failure of multiple other treatment modalities 3. Ages between 18 and 50 years, either sex 4. Completion of detoxification treatment preoperatively with no somatic symptoms of withdrawal and negative morphine urinalysis and naloxone tests