神经电刺激治疗慢性头面部疼痛：综述（二十四）
英语晨读 ·
山东省立医院疼痛科英语晨读已经坚持10余年的时间了，每天交班前15分钟都会精选一篇英文文献进行阅读和翻译。一是可以保持工作后的英语阅读习惯，二是可以学习前沿的疼痛相关知识。我们会将晨读内容与大家分享，助力疼痛学习。
本次文献选自Antony AB, Mazzola AJ, Dhaliwal GS, et al. Neurostimulation for the Treatment of Chronic Head and Facial Pain: A Literature Review[J]. Pain Physician, 2019, 22(5):447-477. 本次学习由陈阳住院医师主讲。
Gasserian Ganglion Stimulation
The Gasserian ganglion of the trigeminal nerve, as discussed, has been a target of stimulation. Reported in 1997, Taub et al described a series of 34 total patients with medically intractable chronic facial pain of which 19 were treated with Gasserian ganglion stimulation postsuccessful temporary trial. Success, defined as at least 50% reduction in pain with stimulator active, was achieved in 5 of 7 patients with diagnosed central pain, 5 of 22 for peripheral pain, and none of the 4 with PHN. The authors concluded that Gasserian ganglion stimulation most effectively treated central pain from stroke. More recently, results have been increasingly favorable. The Gasserian ganglion has been a target for neuropathic pain primarily caused by infliction on the trigeminal nerve either following accidental injuries including surgical or trauma, herpes zoster infection, or a result of postinvasive ablation procedure. Kustermans et al retrospectively analyzed 17 patients with refractory TN who after successful 4-week trial were implanted with a neurostimulation electrode at the level of the Gasserian ganglion. A total of 15 out of the 17 patients exhibited at least 50% pain relief postimplant. Although the pain relief decreased from 6 to 24 months, the authors conclude 44% of patients maintained long-term pain relief after 24 months. Therefore Gasserian ganglion stimulation is promising and should be considered prior to invasive treatments such as motor cortex stimulation or deep brain stimulation.
半月节刺激
如上所述，三叉神经的半月节已成为刺激的靶点。Taub等人于1997年发表文章，收集了共34例药物难治性慢性面部疼痛的患者，其中19例在临时测试成功后通过半月节刺激治疗。成功被定义为在使用刺激器的情况下疼痛至少减少了50％，在7例被诊断为中枢疼痛的患者中有5例获得了成功，22例外周痛中有5例获得了成功，而4例PHN的患者中没有一个。作者得出结论，半月节刺激有效地治疗了中风引起的中枢性疼痛。最近，结果变得越来越有利。半月节已成为主要由意外伤害（包括外科手术或外伤）、带状疱疹感染或侵入性消融手术导致对三叉神经造成伤害而引起神经性疼痛的靶点。Kustermans等人回顾性分析了17例难治性TN患者，这些患者在成功进行了4周的测试后，植入了位于半月节水平的神经刺激电极。在17名患者中，共有15名在植入后表现出至少50％的疼痛缓解。尽管疼痛缓解能力从6个月到24个月有所下降，但作者得出的结论是，有44％的患者在24个月后可以长期缓解疼痛。因此，半月节刺激是有前途的，应在侵入性治疗（例如运动皮层刺激或脑深部刺激）之前考虑。
Future Treatments on the Horizon
With advancing technology, new devices have been developed that are smaller and take advantage of wireless capabilities. This allows for the implantation of tiny leads without the need for a larger implantable power source. One case report describes efficacy of a supraorbital implantation of 2 octopolar wireless neurostimulators with an external pulse generator for a patient with posttraumatic neuralgia. Stimulation was given at HF (10 kHz) over the supraorbital nerve and patient reported a decrease in pain from 8 to 2 at both 12- and 24-month follow-up. In theory, a smaller wireless device can lead to a less invasive implantation and fewer complications including skin erosion, lead migration, and local pain.
未来疗法展望
随着技术的进步，已经开发出了体积更小并且能够利用无线功能的新设备。这允许植入细小的电极，而无需更大的可植入电源。一项病例报告描述了眶外植入2枚带有外部脉冲发生器的八极无线神经刺激器对创伤后神经痛患者的疗效。在眶上神经以HF（10 kHz）刺激，患者报告在12个月和24个月的随访中疼痛从8减轻到2。从理论上讲，较小的无线设备可以减轻植入创伤，并减少并发症，包括皮肤损坏、电极移位和局部疼痛。
As aforementioned, currently there are implantable on-demand wireless microstimulators that affords the patient the ability to actively control stimulation themselves, as needed. Autonomic Technologies Inc. neurostimulation is now referred to as SPG microstimulation therapy and is available in the European Union for the treatment of episodic and chronic CH. Currently, SPG microstimulation remains investigational in the United States. Pietzsch et al reviewed the Pathway CH-1 study by Schoenen et al and concluded that SPG stimulation has positive outcomes in patients with chronic CH and may provide an overall health care cost savings within 5 years poststimulation. Although this study assumes the results from the Pathway CH-1 study can be generalized to the entire population suffering from CH, it suggests this neuromodulation technique, while providing better health outcomes, can also simultaneously improve cost-efficacy over time.
如前所述，当前存在可植入的按需无线微型刺激器，该微型刺激器使患者能够根据需要自己主动控制刺激。Autonomic Technologies Inc.的神经刺激器主要用于SPG微刺激疗法，在欧盟被批准用于治疗发作性和慢性CH。目前，SPG微刺激在美国仍处于研究阶段。 Pietzsch等人回顾了Schoenen等人的Pathway CH-1研究，得出的结论是SPG刺激对慢性CH患者具有积极的效果，并且可以在刺激后5年内节省总体医疗费用。尽管该研究是假设可以将Pathway CH-1研究的结果推广到患有CH的整个人群，但它表明这种神经调节技术在提供更好疗效的同时，还可以随着时间的流逝提高成本效益。