Small Fiber Neuropathy
Conditions
Keywords
Small Fiber Neuropathy, Intra-Epidermal Nerve Fiber Density, IENFD, Spinal Cord Stimulation, SCS, ECAP-Controlled Stimulation, Closed-Loop Stimulation, Saluda Evoke, Quantitative Sensory Testing, QST, Neuropathic Pain, Mixed Neuropathy, EMG/NCS
Brief summary
This prospective observational pilot study will evaluate structural, functional, and patient-reported outcomes in adults with small fiber neuropathy who receive Saluda Evoke ECAP-controlled spinal cord stimulation as part of routine clinical care. The study does not assign, direct, or modify spinal cord stimulation therapy. All decisions regarding patient selection, trial stimulation, permanent implantation, and device programming are made independently by the treating physician according to standard clinical practice. The primary objective is to assess change in intra-epidermal nerve fiber density from baseline to 12 months. Secondary objectives include evaluation of quantitative sensory testing, pain intensity, patient-reported outcomes, and correlations between changes in nerve fiber density, sensory function, and neuropathic pain outcomes. The study will enroll up to 10 adult participants with clinically diagnosed small fiber neuropathy and chronic neuropathic pain. Research assessments include patient-reported outcome measures, quantitative sensory testing, review of available clinical records, and a 12-month follow-up skin biopsy for intra-epidermal nerve fiber density. This aligns with the approved protocol: observational, 10 adults, 12-month participant follow-up, primary IENFD endpoint, and secondary QST/pain/correlation endpoints.
Interventions
DEVICEEvoke SCS system
Spinal cord stimulation using the Saluda Evoke system, an ECAP-controlled closed-loop SCS device that monitors neural response and adjusts stimulation in real time. Participants receive SCS therapy as part of routine clinical care. The study observes structural, sensory, pain, and patient-reported outcomes over 12 months and does not assign, direct, or modify device use, implantation, or programming. This matches the protocol's device description and keeps the intervention generic enough for ClinicalTrials.gov while still identifying the Saluda Evoke system.
Sponsors
TriCity Research Center
Saluda Medical Americas, Inc.
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
19 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Age 19 years or older. * Clinically diagnosed small fiber neuropathy based on abnormal intra-epidermal nerve fiber density (IENFD) skin biopsy. * Chronic neuropathic pain with Numeric Pain Rating Scale score of at least 6. * Candidate for ECAP-controlled spinal cord stimulation therapy based on the - - - Principal Investigator's medical judgment. * Able and willing to undergo baseline and 12-month skin biopsies. * Able to comply with 12-month quantitative sensory testing. * Able to provide informed consent.
Exclusion criteria
* Confounding factors that may independently contribute to small fiber damage or alter nerve fiber density, including uncontrolled diabetes defined as HbA1c greater than 8.5% within the last 3 months, autoimmune disorders such as lupus, or history of alcohol abuse. * Contraindications to spinal cord stimulation therapy, including active infection, coagulation disorders, allergy to medical device components, or other relevant surgical/device contraindications. * Uncontrolled medical or psychiatric conditions. * Pregnancy or planning to become pregnant during the study period.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Intra-Epidermal Nerve Fiber Density From Baseline to 12 Months | Baseline to 12 months | Change in intra-epidermal nerve fiber density measured by skin biopsy from baseline to 12 months in participants with small fiber neuropathy receiving ECAP-controlled spinal cord stimulation as part of routine clinical care. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in Thermal Detection Thresholds From Baseline to 12 Months | Baseline to 12 months | Change in heat and cold detection thresholds measured by quantitative sensory testing as a functional measure of small fiber integrity. |
| Change in Numeric Pain Rating Scale Score Over 12 Months | Baseline, 1 week, 3 months, 6 months, and 12 months | Change in pain intensity measured using the Numeric Pain Rating Scale. The Numeric Pain Rating Scale is an 11-point scale from 0 to 10, where 0 indicates no pain and 10 indicates the worst pain imaginable. Higher scores indicate worse pain. |
| Patient Global Impression of Change Score Over 12 Months | 1-week, 3 months, 6 months, and 12 months | Participant-reported overall impression of change measured using the Patient Global Impression of Change scale. The scale ranges from 1 to 7, where 1 indicates no change or worsening and 7 indicates a great deal better and a considerable improvement that has made all the difference. Higher scores indicate greater improvement. |
| Correlation Between Change in IENFD and Change in Quantitative Sensory Testing Thresholds | Baseline to 12 months | Correlation between change in intra-epidermal nerve fiber density measured by skin biopsy and change in heat and cold detection thresholds measured by quantitative sensory testing from baseline to 12 months.. |
| Correlation Between Change in IENFD and Change in Pain Intensity | Baseline to 12 months | Correlation between change in intra-epidermal nerve fiber density measured by skin biopsy and change in pain intensity measured using the Numeric Pain Rating Scale from baseline to 12 months. The Numeric Pain Rating Scale is an 11-point scale from 0 to 10, where 0 indicates no pain and 10 indicates the worst pain imaginable. Higher scores indicate worse pain. |
Countries
United States
Contacts
PRINCIPAL_INVESTIGATORPravardhan Birthi, M.D.
TriCity Research Center, LLC
STUDY_DIRECTORMahesh Pattabiraman, Ph.D.
TriCity Research Center
Outcome results
None listed