Local Cerebral Oxygenation in Chronic Pain Patients Utilizing Spinal Cord Stimulation

Inclusion Criteria:

1. Be 18 years of age or older at the time of enrolment

2. Diagnosed with chronic, intractable pain of the trunk and/or limbs, which has beenrefractory to conservative therapy for a minimum of 6 months

3. Subject has a minimum Visual Analog Scale (VAS) score of 50 mm or higher (where 100mm indicates the worst imaginable pain) at baseline or a 5 on a Numerical RatingScale (NRS)

4. Be an appropriate candidate for the surgical procedures required in this study basedon the clinical judgment of the implanting physician

5. Be willing and capable of giving informed consent

6. Be willing and able to comply with study-related requirements, procedures, andvisits

Exclusion Criteria:

1. Subject is pregnant or nursing

2. Have a medical condition or pain in other area(s), not intended to be treated withSCS, that could interfere with study procedures, as determined by the Investigator

3. Have evidence of an active disruptive psychological or psychiatric disorder or otherknown condition significant enough to impact perception of pain, compliance ofintervention, and/or ability to evaluate treatment outcomes

4. Have an existing drug pump and/or SCS system or another active implantable devicesuch as a pacemaker, deep brain stimulator (DBS), or sacral nerve stimulator (SNS)

5. Have prior experience with SCS

6. Be concomitantly participating in another clinical study

7. Subject has secondary gain issues that could interfere with the study measures oroutcomes

8. Subject is contraindicated for use of non-invasive cerebral oxygenation measurements (e.g., at risk for sensor displacement such as facial cosmetic. Non-intact skin onthe forehead, or ENT surgery)

9. Subject is allergic to any adhesives, materials or fluids in or used in conjunctionwith the CereVu sensor