Dinsmoor David A, Usoro Joshua O, Barka Noah D, Billstrom Tina M, Litvak Leonid M, Poree Lawrence R
Medtronic plc, Minneapolis, MN, USA.
Department of Anesthesia, University of California San Francisco Pain Management Center, San Francisco, CA, USA.
Pain Rep. 2022 Nov 11;7(6):e1047. doi: 10.1097/PR9.0000000000001047. eCollection 2022 Nov-Dec.
Unlike conventional dorsal spinal cord stimulation (SCS)-which uses single pulses at a fixed rate-burst SCS uses a fixed-rate, five-pulse stimuli cluster as a treatment for chronic pain; mechanistic explanations suggest burst SCS differentially modulate the medial and lateral pain pathways vs conventional SCS. Neural activation differences between burst and conventional SCS are quantifiable with the spinal-evoked compound action potential (ECAP), an electrical measure of synchronous neural activation.
We implanted 7 sheep with a dorsal stimulation lead at T9/T10, a dorsal ECAP sensing lead at T6/T7, and a lead also at T9/T10 but adjacent to the anterolateral system (ALS). Both burst and conventional SCS with stimulation amplitudes up to the visual motor threshold (vMT) were delivered to 3 different dorsal spinal locations, and ECAP thresholds (ECAPTs) were calculated for all combinations. Then, changes in ALS activation were assessed with both types of SCS.
Evoked compound action potential thresholds and vMTs were significantly higher ( < 0.05) with conventional vs burst SCS, with no statistical difference ( > 0.05) among stimulation sites. However, the vMT-ECAPT window (a proxy for the useable therapeutic dosing range) was significantly wider ( < 0.05) with conventional vs burst SCS. No significant difference ( > 0.05) in ALS activation was noted between conventional and burst SCS.
When dosed equivalently, no differentially unique change in ALS activation results with burst SCS vs conventional SCS; in addition, sub-ECAPT burst SCS results in no discernable excitability changes in the neural pathways feeding pain relevant supraspinal sites.
与传统的背侧脊髓刺激（SCS）不同，传统SCS以固定频率使用单脉冲，而爆发式SCS使用固定频率的五脉冲刺激簇来治疗慢性疼痛；机制解释表明，与传统SCS相比，爆发式SCS对内侧和外侧疼痛通路的调节有所不同。爆发式SCS和传统SCS之间的神经激活差异可以通过脊髓诱发复合动作电位（ECAP）进行量化，ECAP是一种同步神经激活的电测量方法。
我们给7只绵羊在T9/T10植入背侧刺激电极，在T6/T7植入背侧ECAP传感电极，并在T9/T10也植入一个靠近前外侧系统（ALS）的电极。将刺激幅度高达视觉运动阈值（vMT）的爆发式SCS和传统SCS都施加到3个不同的背侧脊髓位置，并计算所有组合的ECAP阈值（ECAPTs）。然后，用两种类型的SCS评估ALS激活的变化。
与爆发式SCS相比，传统SCS的诱发复合动作电位阈值和vMTs显著更高（<0.05），刺激部位之间无统计学差异（>0.05）。然而，与爆发式SCS相比，传统SCS的vMT-ECAPT窗口（可用于治疗剂量范围的指标）显著更宽（<0.05）。传统SCS和爆发式SCS之间在ALS激活方面没有显著差异（>0.05）。
当剂量相等时，爆发式SCS与传统SCS相比，在ALS激活方面没有差异独特的变化；此外，低于ECAPT的爆发式SCS不会导致与疼痛相关的脊髓上部位的神经通路出现可察觉的兴奋性变化。
