Assessment of Neurophysiological Effects of Medication Tapering During Treatment With ECAP Controlled Closed-loop Spinal Cord Stimulation Trial Periods
试验速览
- 阶段
- 不适用
- 状态
- 招募中
- 发起方
- 入组人数
- 50
- 试验地点
- 1
- 主要终点
- Spinal cord sensitivity expressed in ECAP amplitude (µV) as a function of the SCS stimulation amplitude (mA).
研究概览
简要总结
This study is being conducted in patients who will receive a spinal cord stimulator. This device helps manage chronic neuropathic pain in the trunk and/or limbs. The patients will receive a spinal cord stimulator that is available, notified, and reimbursed in Belgium, which uses a special technology automatically adjusting the intensity of the stimulation. This is called a closed-loop system.
The closed-loop system stimulates the Beta fibers in the spinal cord and simultaneously measures their response. Based on the measured response, the stimulation strength is automatically adjusted. In Belgium, after implant of the leads the effect must first be evalauted for 3 weeks before implanting the Internal Pulse Generator; this is called the trial period. Only if the trial is successful, the patients will receive a permanent implant.
The primary goal of the study is to evaluate how different types of pain medication influence the neurophysiological response of the Beta fibers during spinal cord stimulation. Patients will be divided into three groups, based on the medication they are taking before receiving a spinal cord stimulator:
- patients not taking any pain medication,
- patients taking strong opioids,
- patients taking anticonvulsant medication.
As part of the study, patients will follow the normal clinical schedule. During visits, they will be asked questions about their pain, sleep, medication use, and activity. The study will end one month after the patient receives the permanent spinal cord stimulator implant.
详细描述
Chronic neuropathic pain, particularly in patients with Persistent Spinal Pain Syndrome Type 2 (PSPS-T2, formerly FBSS), remains a major therapeutic challenge. Spinal cord stimulation (SCS) is an established therapy for patients with refractory pain. In Belgium, a 21-day trial period with an externalized epidural lead is mandatory before permanent implantation. During this trial, pain relief, improved sleep, increased activity, and reduction in pain medication intake must be documented in order to qualify for a permanent implant.
The Evoke™ Closed-Loop SCS system (Saluda Medical) is a CE-marked device used within its licensed indication in this study. This system uniquely records Evoked Compound Action Potentials (ECAPs) from the spinal cord, allowing continuous monitoring of neural activation. Closed-loop algorithms adjust stimulation output in real time based on measured ECAPs, thereby aiming to deliver consistent therapy within each patient's therapeutic window.
Recent pilot data and case reports have suggested that reductions in pain medication, particularly strong opioids and anticonvulsants, may alter spinal cord sensitivity to stimulation and ECAP parameters. A prospective pilot study performed at ZAS St. Augustinus Hospital (Belgium) demonstrated measurable changes in spinal cord sensitivity after medication reduction in patients implanted with the Evoke system. These findings suggest that medication tapering may influence neurophysiological responsiveness to SCS and highlight the importance of documenting this relationship systematically.
Study Design
This is a multicenter, open-label, prospective observational study enrolling 50 patients scheduled for SCS with the Evoke closed-loop system. Patients will be stratified into three groups according to baseline pain medication use:
研究设计
- 研究类型
- Observational
- 观察模型
- Cohort
- 时间视角
- Prospective
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Patient deemed a suitable candidate for SCS and routinely scheduled to undergo a trial phase with the Evoke SCS system.
- •Diagnosis of Persistent Spinal Pain Syndrome Type 2 (lower spine).
- •Current medication use:
- •No strong opioids or anticonvulsants, or other analgesics
- •Monotherapy with a strong opioid, or
- •Monotherapy with an anticonvulsant.
- •Willing and able to provide written informed consent to participate, based on a voluntary agreement after a full explanation of the study.
- •Age ≥ 18 years at the time of enrollment.
- •Willing and able to comply with study requirements, procedures, and follow-up visits.
排除标准
- •Evidence of an active disruptive psychological or psychiatric disorder, or other condition significant enough to impact pain perception, compliance with intervention, or ability to evaluate outcomes (as determined by the investigator in consultation with a clinical psychologist).
- •Current diagnosis of a progressive neurological disease such as multiple sclerosis, chronic inflammatory demyelinating polyneuropathy, rapidly progressive arachnoiditis, rapidly progressive diabetic peripheral neuropathy, brain or spinal cord tumor, or severe/critical spinal stenosis.
- •Current diagnosis or condition such as coagulation disorder, bleeding diathesis, platelet dysfunction, progressive peripheral vascular disease, or uncontrolled diabetes mellitus that presents excess risk for the procedure (as determined by the investigator).
- •Active systemic or local infection.
- •Pregnancy.
- •Within 6 months prior to enrollment: significant untreated addiction to dependency-producing medications or a history of substance abuse (including alcohol or illicit drugs).
研究组 & 干预措施
Without strong opioids or anticonvulsants or other analgesic drugs
Patients with Persistent Spinal Pain Syndrome Type 2 (PSPS-T2) (lower spine) who are not taking any analgesic medication.
干预措施: Spinal Cord Stimulation with Evoke Closed-Loop System (Other)
Monotherapy with strong opioids
Patients with Persistent Spinal Pain Syndrome Type 2 (PSPS-T2) (lower spine) treated with analgesic monotherapy consisting of strong opioids (e.g., morphine, oxycodone, hydromorphone, fentanyl, methadone, oxymorphone).
干预措施: Spinal Cord Stimulation with Evoke Closed-Loop System (Other)
Monotherapy with anticonvulsants
Patients with Persistent Spinal Pain Syndrome Type 2 (PSPS-T2) (lower spine) treated with analgesic monotherapy consisting of anticonvulsants (e.g., gabapentin, pregabalin, carbamazepine, lamotrigine, topiramate).
干预措施: Spinal Cord Stimulation with Evoke Closed-Loop System (Other)
结局指标
主要结局
Spinal cord sensitivity expressed in ECAP amplitude (µV) as a function of the SCS stimulation amplitude (mA).
时间窗: From start of SCS trial (baseline) to 1 month after permanent implantation.
Spinal cord sensitivity to spinal cord stimulation (SCS), will be assessed using activation plots describing the relationship between SCS stimulation current (mA) and the resultant Evoked Compound Action Potential (ECAP) amplitude (µV). Change is spinal cord sensitivity (µV/mA) will be compared between the SCS trial phase and at 1 month after permanent implantation across the different medication groups.
次要结局
- Change in pain intensity measured using a 10 cm Visual Analog Scale (VAS)(From start of SCS trial (baseline) to 1 month after permanent implantation.)
- Change in pain medication intake measured via Belgian Pain Platform (BPP) and clinical verification(From start of SCS trial (baseline) to 1 month after permanent implantation.)
- Change in neurophysiological parameters such as conduction velocity (m/sec), rheobase (mA) and chronaxie (µs), measured using the Evoke system's neurophysiological assessment tools.(From start of SCS trial (baseline) to 1 month after permanent implantation.)
研究者
Dr. Tony Van Havenbergh
Chairman, Department of Neurosurgery (NeurochirurgieGroep); Director, Antwerp Skull Base Team; Director, Brai²n
Brai²n