A Call to Action Toward Optimizing the Electrical Dose Received by Neural Targets in Spinal Cord Stimulation Therapy for Neuropathic Pain

Chakravarthy, Krishnan; Reddy, Rajiv; Al‐Kaisy, Adnan; Yearwood, Thomas; Grider, Jay S.

doi:10.2147/jpr.s323372

Cited by 7 publications

(7 citation statements)

References 63 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Recognizing the criticality of appropriately dosing the SCS to achieve optimal therapeutic outcomes, we agree with Dietz et al 18 regarding the need to understand how to best translate dosing-relevant preclinical findings-ie, stimulation amplitudes referenced to MTs in rats-to clinical use cases. 18,34 Although caution is warranted when comparing results between reports owing to differences in SCS rates and PWs, our findings in anesthetized rats do not agree with the large disparity between vMT and ECAPT reported by Dietz et al 18 In their work using 2-Hz, 20-μs PW SCS, they note a vMT:ECAPT ratio of 13.4. For this reason, they conclude that vMT referenced SCS (at 66%-90% of the vMT, for instance) in anesthetized rats may result in spinal cord activation significantly greater than that employed clinically.…”

Section: Ecapt Vmt and Scs Amplitudescontrasting

confidence: 84%

Spinal Evoked Compound Action Potentials in Rats With Clinically Relevant Stimulation Modalities

Cedeño¹,

Vallejo²,

Kelley³

et al. 2023

Neuromodulation: Technology at the Neural Interface

View full text Add to dashboard Cite

Section: Ecapt Vmt and Scs Amplitudescontrasting

confidence: 84%

Spinal Evoked Compound Action Potentials in Rats With Clinically Relevant Stimulation Modalities

Cedeño¹,

Vallejo²,

Kelley³

et al. 2023

Neuromodulation: Technology at the Neural Interface

View full text Add to dashboard Cite

“…In conjunction with selecting the optimal dose, consistent dosing —that is, maintaining a consistent VTA throughout therapy—is critical to optimizing therapeutic outcomes. 33 …”

Section: Compensating For Motion: Closed-loop Control Considerations For Scsmentioning

confidence: 99%

A New Direction for Closed-Loop Spinal Cord Stimulation: Combining Contemporary Therapy Paradigms with Evoked Compound Action Potential Sensing

Vallejo¹,

Chakravarthy²,

Will³

et al. 2021

JPR

Self Cite

View full text Add to dashboard Cite

Spinal cord stimulation (SCS) utilizes the delivery of mild electrical pulses via epidural electrodes placed on the dorsal side of the spinal cord, typically to treat chronic pain. The first clinical use of SCS involved the delivery of paresthesia inducing, low-frequency waveforms to the neural targets corresponding to the painful areas. Contemporary SCS therapies now leverage novel therapeutic pathways to limit paresthesia and deliver superior clinical outcomes. Historically, SCS has largely been delivered with fixed stimulation parameters. This approach, referred to as open-loop (OL) SCS, does not account for the fluctuations in spacing—driven by postural changes and activity—between the electrodes and the cord. These fluctuations result in variability in the delivered dose and the volume of tissue activation (VTA) that manifests with each stimulation pulse. Inconsistent dosing may lead to suboptimal therapeutic efficacy and durability. To address this clinical need, closed-loop (CL) SCS systems have been developed to automatically adjust stimulation parameters to compensate for this variability. The evoked compound action potential (ECAP), a biopotential generated by the synchronous activation of dorsal column fibers, is indicative of the VTA resulting from the stimulation pulse. The ECAP may be utilized as a control signal in CL SCS systems to adjust stimulation parameters to reduce variability in the ECAP, and in turn, variability in the VTA. While investigational CL SCS systems with ECAP sensing have so far focused solely on managing paresthesia-based SCS, such systems must also incorporate the stimulation approaches that now define the contemporary clinical practice of SCS. Accordingly, we describe here a flexible, next-generation framework for neural responsive SCS that blends science-based methodologies for pain management with real-time CL control for biophysical variation. We conclude with a clinical example of such a system and the associated performance characteristics.

show abstract

“…In contrast, the inherently dynamic relationship between the electrodes and spinal cord in all SCS paradigms means that open-loop SCS (OL-SCS) may not always produce the optimal neural response ( figure 1 ). 13 …”

Section: Introductionmentioning

confidence: 99%

Durable multimodal and holistic response for physiologic closed-loop spinal cord stimulation supported by objective evidence from the EVOKE double-blind randomized controlled trial

Kapural¹,

Mekhail²,

Costandi³

et al. 2023

Reg Anesth Pain Med

View full text Add to dashboard Cite

IntroductionChronic pain patients may experience impairments in multiple health-related domains. The design and interpretation of clinical trials of chronic pain interventions, however, remains primarily focused on treatment effects on pain intensity. This study investigates a novel, multidimensional holistic treatment response to evoked compound action potential-controlled closed-loop versus open-loop spinal cord stimulation as well as the degree of neural activation that produced that treatment response.MethodsOutcome data for pain intensity, physical function, health-related quality of life, sleep quality and emotional function were derived from individual patient level data from the EVOKE multicenter, participant, investigator, and outcome assessor-blinded, parallel-arm randomized controlled trial with 24 month follow-up. Evaluation of holistic treatment response considered whether the baseline score was worse than normative values and whether minimal clinical important differences were reached in each of the domains that were impaired at baseline. A cumulative responder score was calculated to reflect the total minimal clinical important differences accumulated across all domains. Objective neurophysiological data, including spinal cord activation were measured.ResultsPatients were randomized to closed-loop (n=67) or open-loop (n=67). A greater proportion of patients with closed-loop spinal cord stimulation (49.3% vs 26.9%) were holistic responders at 24-month follow-up, with at least one minimal clinical important difference in all impaired domains (absolute risk difference: 22.4%, 95% CI 6.4% to 38.4%, p=0.012). The cumulative responder score was significantly greater for closed-loop patients at all time points and resulted in the achievement of more than three additional minimal clinical important differences at 24-month follow-up (mean difference 3.4, 95% CI 1.3 to 5.5, p=0.002). Neural activation was three times more accurate in closed-loop spinal cord stimulation (p<0.001 at all time points).ConclusionThe results of this study suggest that closed-loop spinal cord stimulation can provide sustained clinically meaningful improvements in multiple domains and provide holistic improvement in the long-term for patients with chronic refractory pain.Trial registration numberNCT02924129.

show abstract

A Call to Action Toward Optimizing the Electrical Dose Received by Neural Targets in Spinal Cord Stimulation Therapy for Neuropathic Pain

Cited by 7 publications

References 63 publications

Spinal Evoked Compound Action Potentials in Rats With Clinically Relevant Stimulation Modalities

Spinal Evoked Compound Action Potentials in Rats With Clinically Relevant Stimulation Modalities

A New Direction for Closed-Loop Spinal Cord Stimulation: Combining Contemporary Therapy Paradigms with Evoked Compound Action Potential Sensing

Durable multimodal and holistic response for physiologic closed-loop spinal cord stimulation supported by objective evidence from the EVOKE double-blind randomized controlled trial

Contact Info

Product

Resources

About