Closed-Loop Deep Brain Stimulation for Refractory Chronic Pain

Inclusion Criteria: 1. Age 22-80 years old 2. Clinical diagnosis of a refractory chronic pain syndrome including 1. post-traumatic pain syndromes (e.g. root avulsions, nerve crush injuries, spinal cord injury) 2. postsurgical pain syndromes (e.g., postmastectomy syndrome, post-thoracotomy syndrome, phantom limb pain, post-surgical spinal pain) 3. postherpetic neuralgia 4. complex regional pain syndrome 5. atypical facial pain 6. central pain syndromes (e.g. post-stroke pain, multiple sclerosis pain, post-radiation pain) 7. post-radiation plexopathy 3. Two or more years or more of medically refractory severe pain 4. Average daily pain for the past 30 days reported as \>6 on a 0-10 numeric rating scale (NRS) 5. Pain that fluctuates over a range of at least 3 points on the NRS 6. Patient has failed at least two pain medications from different classes as determined by a neurologist or pain management specialist with stable doses of medications for 30 days prior to baseline visit. 7. Lack of a surgically correctible etiology for the pain as determined by 2 independent surgeons 8. Ability to speak / read English 9. Capable of understanding and providing informed consent 10. Absence of significant cognitive impairment - score of 25 or greater on the Montreal Cognitive Assessment (MoCA) 11. Successful detection of pain biomarkers or positive symptomatic response to inpatient stimulation trial period if performed. Exclusion Criteria: 1. Major medical co-morbidities increasing the risk of surgery including uncontrolled hypertension, coagulopathy, severe diabetes, major organ system failure, active infection or history of implant related infections, immunocompromised state or malignancy with \< 5 years life expectancy 2. Presence of cardiac pacemakers/defibrillators, implanted medication pumps, intra-cardiac lines, any intracranial implants (e.g., aneurysm clip, shunt, cochlear implant, electrodes) or other implanted stimulators not compatible with RC+S system 3. Pregnancy or breast feeding: all women of child bearing potential will have a negative urine pregnancy test prior to undergoing their surgical procedure. 4. Active depression (BDI \> 20), Suicide attempt \</= 12 months or imminent suicide risk, or other untreated or uncontrolled psychiatric illness that evaluating psychiatrist would recommend exclusion of patient after neuropsychiatric evaluation. 5. History of substance abuse in past 3 years 6. Inability to stop anticoagulation or platelet anti-aggregation …