Nuffield Department of Surgical Sciences, University of Oxford, Oxford, UK.
Nuffield Department of Anaesthetics, John Radcliffe Hospital, Oxford, UK.
Neuromodulation. 2020 Feb;23(2):245-251. doi: 10.1111/ner.12959. Epub 2019 May 9.
To quantify the relationship between the electrical power requirement to achieve pain relief and the position of the active electrode of dorsal root ganglion stimulators within the spinal nerve root exit foramen.
Retrospective analysis of prospectively collected data of 92 consecutive patients undergoing dorsal root ganglion stimulation (DRGS) for chronic pain in a single center. Cervical and sacral cases, and failed trials/explanted DRGS were excluded, so we report on 57 patients with 78 implanted leads. Anteroposterior and lateral fluoroscopic images of the lead in the exit foramen were examined, and the active electrode positions were put into categories depending on their location relative to fixed anatomical landmarks. The clinical outcome and the power requirements for each of these groups of electrodes were then analyzed. Overall pain outcome was assessed by numeric pain rating scale score pre-operatively and post-operatively.
There was no significant relationship between power requirements and mediolateral electrode position, although the lowest average was observed with electrode positions directly below the center of the pedicle. On lateral x-ray, the lowest power requirements were observed in the electrodes positioned superodorsally or dorsally within the foramen. Importantly, power requirements in this location were consistently low, while the power requirements in other locations were not only higher but also much more variable. Electrodes in the superodorsal position required a median output power almost four times lower than electrodes in other positions (p = 0.002). Clinical outcome was not significantly related to power requirement or foraminal position.
Aiming for a superodorsal electrode position on lateral intraoperative fluoroscopy is desirable, since siting leads in this location reduces the required stimulator output power very substantially and thus will extend battery life. Position within the foramen does not determine clinical outcome, and so the implanter can safely aim for the low power site without detriment to the analgesic efficacy of the system.
定量研究达到缓解疼痛所需的电力与背根神经节刺激器（DRGS）的活动电极在脊神经根出孔内位置之间的关系。
对单中心连续 92 例接受 DRGS 治疗慢性疼痛的患者前瞻性收集数据进行回顾性分析。排除颈椎和骶骨病例以及失败试验/植入式 DRGS，因此我们报告了 57 例患者共 78 个植入式导联。检查了导线下出口孔的前后位和侧位荧光透视图像，并根据其与固定解剖学标志的相对位置将活动电极位置分类。然后分析了这些电极组的临床结果和功率需求。总体疼痛结果通过手术前后数字疼痛评分量表评分进行评估。
功率需求与电极的内外侧位置之间无显著关系，尽管观察到电极位于椎弓根中心正下方时平均功率最低。在侧位 X 光片上，位于孔内最上方和背侧的电极所需的功率最低。重要的是，该位置的功率需求始终较低，而其他位置的功率需求不仅更高，而且变化更大。位于最上方和背侧的电极所需的输出功率中位数几乎比其他位置的电极低四倍（p = 0.002）。临床结果与功率需求或出孔位置无显著关系。
在术中侧位荧光透视时，理想的目标是放置一个位于最上方和背侧的电极，因为将导联放置在此位置可大大降低所需刺激器输出功率，从而延长电池寿命。出孔内的位置并不能决定临床结果，因此植入者可以安全地选择低功率部位，而不会对系统的镇痛效果造成不利影响。
