StruCtuRal And FuncTional Brain Alterations by Conventional Spinal Cord Stimulation And High DensitY Stimulation

Study Overview
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Brief Summary
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This study is an interventional prospective observatory single center trial, investigating the supraspinal effects of long term conventional SCS (60 Hz) and paresthesia-free high density SCS in failed back surgery syndrome (FBSS) patients with back and leg pain completed with resting state functional magnetic resonance (rs fMRI) and voxel-based magnetic resonance morphometry (VBM).

Detailed Description
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When patient meets all inclusion criteria and no exclusion criteria, a neuroimaging protocol will be obtained at baseline, prior to trial implantation of SCS. At trial implantation a Vectris® SureScan® MRI 1x8 lead will be implanted, targeted by intraoperative mapping. This lead will be connected to a temporary extension cable and ENS. Normal trial period will be respected based on the reimbursement rules in Belgium (4 weeks). When the patient is eligible for implantation of the definitive SCS system (more than 50% pain reduction and/or more than 50% reduction in pain medication), patient will undergo surgery for definitive implantation. Then the Vectris® SureScan® MRI lead will be connected to a RestoreSensor® SureScan® MRI neurostimulator. After stabilisation of the stimulation parameters at least for more than 1 month, the second session of neuroimaging will occur (T1) with the RestoreSensor® SureScan® MRI neurostimulator in MRI mode. Minimal one month later ( 2 months after implantation of definitive SCS system) the patient will undergo the last session of neuroimaging (T2) with the stimulator in MRI mode. During that period prior to the MR-session, a new protocol will occur with paresthesia free high density SCS. The MRI protocol will occur after stabilisation of the stimulation parameters at least for more than 1 month. During the whole period, patients will fill in a VAS diary (back and leg pain separately) and at time of neuroimaging T1 and T2 a Likert-scale in order to evaluate the satisfaction grade of the patient. Additionally, patients will also wear during the whole period an Actiwatch, measuring sleep patterns and filling in questionnaires at B, T1 and T2 (Pittsburgh Sleep Quality Index (PSQI) and Holland Sleep Disorders Questionnaire (HSDQ).

Official Title
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StruCtuRal And FuncTional Brain Alterations by Conventional Spinal Cord Stimulation And High DensitY Stimulation: a Combined Voxel-based Morphometry and Resting State Functional Connectivity Study

Conditions
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Failed Back Surgery Syndrome

Intervention / Treatment
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* Other: fMRI


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Subject is at least 18 years old. Subject is able and willing to comply with the follow-up schedule and protocol Diagnosis of FBSS with predominant leg pain (VAS) > 5) and non-dominant back pain. Cognitive and language functioning enabling coherent communication between the examiner and the subject; Failed conservative treatments for pain including but not limited to pharmacological therapy and physical therapy Stable neurologic function in the past 30 days In the opinion of the Investigator, the subject is psychologically appropriate for the implantation for an active implantable medical device Subject is able to provide written informed consent Subject speaks Dutch or French. Exclusion Criteria: Female subject of childbearing potential is pregnant/nursing, or plans to become pregnant during the course of the trial Subject has had radiofrequency treatment of an intended target DRG within the past 3 months Subject currently has an active implantable device including ICD, pacemaker, spinal cord stimulator, deep brain stimulator or intrathecal drug pump Subject is unable to operate the device or has no relative available. Subjects with indwelling devices that may pose an increased risk of infection Subject currently has an active infection Subject has, in the opinion of the Investigator, a medical comorbidity that contraindicates placement of an active medical device Subject has participated in another clinical investigation within 30 days Subject has a coagulation disorder or uses anticoagulants that, in the opinion of the investigator, precludes participation Subject has been diagnosed with cancer in the past 2 years Life expectancy < 6 months Imaging (MRI, CT, x-ray) findings within the last 12 months that, in the Investigator's opinion, contraindicates lead placement Existing extreme fear for entering MRI General contraindication for MRI (pacemaker, etc…) Age male/female patient <18 years

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: spinal cord stimulation<br>The Vectris® SureScan® MRI lead will be connected to a RestoreSensor® SureScan® MRI neurostimulator. | Other: fMRI<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Grey Mater Volume assessed by Voxel-based morphometry analysis (based on MRI images) |  | The change between baseline and 1 month after definitive implantation (T1) and the change between baseline and 2 months after definitive implantation (T2). | 
| Functional connectivity analysis using in-house developed software (based on MRI images) |  | The change between baseline and 1 month after definitive implantation (T1) and the change between baseline and 2 months after definitive implantation (T2). | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Visual Analogue Scale (VAS) pain diary |  | Three times every day (morning, afternoon and evening), starting 1 week before baseline measurements up to 2 months until study completion. | 
| Objective sleep quality will be measured using the Actiwatch spectrum plus (Respironics). |  | The difference between 7 days at baseline before implantation and 7 days before T1 ( 1 month after definitive implantation) and 7 days before T2 ( 2 months after definitive implantation). | 
| Subjective sleep quality will be measured by the Pittsburgh Sleep Quality Index (PSQI) |  | The change between baseline and 1 month after definitive implantation (T1) and the change between baseline and 2 months after definitive implantation (T2). | 
| Pain catastrophizing is assessed by the Pain Catastrophizing Scale (PCS) |  | The change between baseline and 1 month after definitive implantation (T1) and the change between baseline and 2 months after definitive implantation (T2). | 
| Likert-scale in order to evaluate the satisfaction grade of the patient. |  | The change between baseline and 1 month after definitive implantation (T1) and the change between baseline and 2 months after definitive implantation (T2). | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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spinal cord stimulation, resting state functional magnetic resonance, voxel-based magnetic resonance morphometry