Neuropathy;Peripheral
Conditions
Keywords
spinal cord stimulation, virtual reality, full body illusion
Brief summary
The study hypothesis is that spinal cord stimulation (SCS) combined with virtual leg illumination (provided through a wearable headset (OculusRift, OculusVR, Irvine, CA) and a custom-designed virtual reality leg scenario) will lead to controlled analgesia induction, boosting analgesic effects obtained with standard SCS treatments and will further be associated with changes in the perception of the affected body part.
Detailed description
Epidural spinal cord stimulation (SCS) is an approved treatment for truncal and extremity neuropathic pain. The mechanisms underlying the efficacy of SCS are unknown. Recent advances in cognitive neuroprosthetics using virtual reality allow for modulation of body perception and bodily experience, which has also been shown to modulate pain perception. The present research proposal plans to merge expertise in cognitive neuroprosthetics with neuromodulation techniques in order to test the analgesic properties of the combination of epidural spinal cord stimulation with a new system of multisensory stimulation based on virtual and enhanced reality (i.e., neuro-visual stimulation). The investigators propose to study this hypothesis prospectively in 25 patients with implanted SCS systems for the treatment of chronic neuropathic pain. Primary outcomes will be pain reduction (based on subjective, functional and physiological measures) and changes in body perception (based on subjective and objective measures). The present study will generate a proof-of-concept for the application of neuro-visual stimulation for the treatment of chronic pain and will form the basis for future NIH funding application.
Interventions
DEVICEneurovisual stimulation
a new system of multisensory stimulation based on virtual and enhanced reality (i.e., neuro-visual stimulation)
Sponsors
Swiss Federal Institute of Technology
Ohio State University
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
OTHER
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
1. Age 18-and older at the time of enrollment 2. Patients carrying a diagnosis of CPRS type 125 or chronic refractory neuropathic leg pain following FBS4 3. Patients who have implanted epidural SCS 4. The SCS implantation for at least three months prior to enrollment 5. Patients with efficacious SCS as defined by ≥ 50% pain improvement after switching SCS from an OFF state to an ON state ('optimal' stimulation efficacy) 6. Patients willing and able to provide informed consent
Exclusion criteria
1. Patients who are unable to effectively or efficiently communicate for example patients suffering from speech deficits (dysarthria, aphasia) or are non-English speaking. 2. Patients with history of prior cranial surgery, significant brain lesions for example intracranial tumors, strokes etc. 3. Non efficacious response to SCS \<50% pain improvement with optimal stimulation parameters 4. Evidence of untreated psychiatric disorders or drugs/alcohol abuse. 5. History of seizures
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Average Pain Reduction Post Intervention | At each hour from 1-5 hours post intervention | 10 point Visual Analog pain rating Scale. Subjective pain perception will be measured by pain ratings on a 10cm visual continuous analog scale (VAS). Patients rate their pain, ranging from no pain (bottom part of the scale) to the worst imaginable pain (upper part of the scale) (Huskisson 1974). The pain reduction will be an average total of the pain scores taken at hours 1, 2, 3, 4, and 5. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Pain Reduction Base on Patient Perception | per minute in each virtual reality condition for 10 minutes in each reality condition. | Validated questionnaires developed by the collaborators (Swiss Federal Institute of Technology) will be used in order to investigate induced changes in leg perception and ownership. In particular, we will assess: 1) feeling of ownership towards the leg shown in the virtual reality set-up (leg ownership); 2) tactile sensations felt on the virtual legs, depending on the different conditions of SCS and visual stimulation. Patients will be asked to indicate how much they agreed with each item using a 7-point colored vertical Likert scale ranging from 0 (complete disagreement, the bottom extreme, red point) to +6 (complete agreement, the top extreme, green point). |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Neurovisual Stimulation Participants in this study will be adults who have already undergone implantation of SCS for the treatment of their pain conditions. The study involves no further treatment or intervention. Subjects will be approached for participation in this study during their routine postoperative clinical visit to the Center for Neuromodulation at the Ohio State University (OSU).All eligible patients will undergo a one-day visit for the virtual reality and full body illusion intervention. This research will also investigate leg embodiment and leg analgesic effects during SCS integrated with different patterns of virtual leg illumination.
neurovisual stimulation: a new system of multisensory stimulation based on virtual and enhanced reality (i.e., neuro-visual stimulation) | 15 |
| Total | 15 |
Baseline characteristics
| Characteristic | Neurovisual Stimulation | — |
|---|---|---|
| Age, Continuous | 47.7 years STANDARD_DEVIATION 9.56 | — |
| Race and Ethnicity Not Collected | — | — Participants |
| Region of Enrollment United States | 15 Participants | — |
| Sex: Female, Male Female | 5 Participants | — |
| Sex: Female, Male Male | 10 Participants | — |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | 0 / 15 |
| other Total, other adverse events | 0 / 15 |
| serious Total, serious adverse events | 0 / 15 |
Outcome results
Primary
Average Pain Reduction Post Intervention
10 point Visual Analog pain rating Scale. Subjective pain perception will be measured by pain ratings on a 10cm visual continuous analog scale (VAS). Patients rate their pain, ranging from no pain (bottom part of the scale) to the worst imaginable pain (upper part of the scale) (Huskisson 1974). The pain reduction will be an average total of the pain scores taken at hours 1, 2, 3, 4, and 5.
Time frame: At each hour from 1-5 hours post intervention
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Neurovisual Stimulation | Average Pain Reduction Post Intervention | 2.72 score on a scale | Standard Error 0.6 |
Secondary
Pain Reduction Base on Patient Perception
Validated questionnaires developed by the collaborators (Swiss Federal Institute of Technology) will be used in order to investigate induced changes in leg perception and ownership. In particular, we will assess: 1) feeling of ownership towards the leg shown in the virtual reality set-up (leg ownership); 2) tactile sensations felt on the virtual legs, depending on the different conditions of SCS and visual stimulation. Patients will be asked to indicate how much they agreed with each item using a 7-point colored vertical Likert scale ranging from 0 (complete disagreement, the bottom extreme, red point) to +6 (complete agreement, the top extreme, green point).
Time frame: per minute in each virtual reality condition for 10 minutes in each reality condition.
Population: Patients will rate their pain reduction on a scale of 0-6, each minute in each of the three virtual reality conditions. The pain score change reported is an average of all time points in all virtual reality settings. A change in pain rating was calculated between different SCS and VR conditions. Percentage pain reduction was then calculated to test whether SCS combined with VR reduced pain more significantly than VR alone. The calculation done was a mean score of all pain ratings at all points.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Neurovisual Stimulation | Pain Reduction Base on Patient Perception | 0.7 average score on scale of pain reduction | Standard Error 0.25 |