1.2 kHz High-Frequency Stimulation as a Rescue Therapy in Patients With Chronic Pain Refractory to Conventional Spinal Cord Stimulation

Abstract

Objectives: We aimed to investigate the efficacy of new subperception stimulation paradigms including 1.2 kHz-highfrequency stimulation (HFS) and advanced-HFS field-shaping algorithm (dorsal horn HFS [DHHFS]) in refractory cases which initially benefited from conventional spinal cord stimulation (SCS) and lost the effect throughout time.Materials and Methods: In the context of a rescue-therapy, patients underwent externalization of the implanted SCS-leads and were tested with multiple combinations of new SCS paradigms. Pain intensity was analyzed using the numeric rating scale (NRS), and data were collected preoperatively and at multiple postoperative follow-ups.Results: Thirty-seven patients underwent externalization of the leads. Mean preoperative NRS-score was 8.1/10 points (SD ± 0.9) for the ON-stimulation period. Patients received a combination of either tonic, burst and 1.2 kHz-HFS, or burst and 1.2 kHz-HFS, DHHFS, or 1.2 kHz-HFS and DHHFS, or 1.2 kHz-HFS alone. The mean postoperative NRS-score after the testingphase was 3.8/10 points (SD ± 2.5), showing a 48.0% mean reduction (p < 0.001). In total, 29 patients reported a significant reduction above 50% in NRS-scores and therefore were reimplanted with new generators that could deliver the new paradigms. Eight patients underwent full SCS-system explantation. The patients who continued with the new paradigms (n = 29) reported mean NRS-scores of 3.5/10 points (SD ± 1.7) 12 months postoperatively, still showing a significant reduction of 43.3% when compared to preoperative scores (p < 0.001). Conclusion:Rescue-therapy with combination of multiple waveforms, including tonic, burst, 1.2 kHz-HFS, and DHHFS, was associated with a significant pain relief in patients with failed conventional SCS. This approach is a safe and efficient and should be considered before explantation of the SCS-system.

The Added Value of Subcutaneous Peripheral Nerve Field Stimulation Combined with SCS, as Salvage Therapy, for Refractory Low Back Pain Component in Persistent Spinal Pain Syndrome Implanted Patients: A Randomized Controlled Study (CUMPNS Study) Based on 3D-Mapping Composite Pain Assessment

“…Burst stimulation appeared in 2013 [56], paresthesia freehigh frequency techniques were developed contemporarily and it took about 5 years for our community to publish counter-studies, counterbalancing the "overly promising" initial results of some of these techniques [57][58][59][60], the objective being to orient us toward the right compromise for our patients, mixing the two approaches as complementary tools: (i) Spatial resolution can be adjusted by the choice of the neural target and new programing capabilities, based on electrical fragmentation of the current; and (ii) temporal resolution can be adjusted by the IPG, as an alternative to tonic conventional SCS or a combination of several waveforms delivered to the patient, the objective being to enhance our ability to personalize SCS therapies [2,61]. As a consequence, some recently marketed adaptors play on the temporal resolution of SCS and give the patient the opportunity to extensively test the different existing waveforms with promising results [62][63][64]. These new insights need to be integrated in our approach to reflect the state of the art, since this paper's ambition is to propose a salvage algorithm.…”

“…Inspired by the previous algorithm and using a similar substrate, our approach now consists in: (1) checking impedance and hardware dysfunction before (2) attempting to reprogram this patient, using either a spatial and/or a temporal retargeting approach, if the patient is complaining of a loss of coverage, or a temporal resolution retargeting approach, if the patient is complaining of a loss in SCS efficacy, despite adequate back pain coverage, given the possibilities of the IPG and existing lead(s). This approach could require SCS system reexploration and, for some patients, conversion using an implanted adaptor, after a new external lead trial [62,63,[65][66][67].…”

The Challenge of Converting “Failed Spinal Cord Stimulation Syndrome” Back to Clinical Success, Using SCS Reprogramming as Salvage Therapy, Through Neurostimulation Adapters Combined with 3D-Computerized Pain Mapping Assessment. A Real-Life Retrospective Cohort Analysis

“…This first step suggested the potential use of adapters in patients presenting LoE, while preserving the preexisting leads already in place. Similarly, Andrade et al (2021) [35] showed that combination of multiple waveforms Burst and HF, used as a salvage therapy, was safe and efficient to decrease pain in 37 patients already implanted with conventional SCS.…”

“…To take the best decision for the patient, one needs to put into the balance the potential drawbacks of the invasiveness of such procedures, given the risk of infection and total explantation. Second, Internal Pulse Generator (IPG) upgrade; addressing the following question: Should we keep the lead(s) in place and change the way they are programmed [20,35,37]? Indeed, over the last 15 years, new SCS paradigms have been developed, relying on different mechanisms of action [38,39] and offering new ways to shape the electrical field, both spatially and temporally.…”

“…With a simple surgical procedure, previously inaccessible SCS programs and waveforms can be used to regain pain relief [17,18]. Proposing new SCS waveforms to rescue patients presenting with FSCSS was recently introduced in clinical practice and showed promising results and significant improvements in patient outcomes [6,11,[19][20][21]. However, the dichotomy between the 2 above-mentioned sub-categories of FSCSS patients, who might both benefit from this new strategy (i.e.…”