Timarova Gabriela, Šteňo Andrej
2nd Department of Neurology, Faculty of Medicine, Comenius University, Dérer's University Hospital, Limbova str.5, 83305, Bratislava, Slovak Republic.
Department of Neurosurgery, Faculty of Medicine, Comenius University, Dérer's University Hospital, Bratislava, Slovak Republic.
BMC Neurol. 2017 Jun 15;17(1):113. doi: 10.1186/s12883-017-0892-4.
Vagal nerve stimulation (VNS) for refractory epilepsy is well established. Trigeminal neuralgia itself is a common disease in adults, and thus, late-onset pain in the trigeminal region under VNS, which is extremely rare, may not be recognized as caused by VNS.
Two patients with drug-resistant symptomatic epilepsy treated with chronic VNS experienced stimulation-related pain in the lower and upper jaw and teeth on the side of stimulation. No evidence of local spread of the stimulation current was present. The pain started with a delay of years after device implantation and weeks after the last increase in the pacing parameters. At the time of onset, the pain was not recognized as VNS-related, leading to extensive examinations. The trigeminal neuralgia-like pain resolved after adjustment of the stimulation current intensity. In one of the patients, the pain disappeared within one to two days following every epileptic seizure. To our knowledge, this is the first case report of late-onset trigeminal pain under VNS revealing a direct link between epileptogenic and pain processes.
A painless interval between the last change of the pacing parameters and trigeminal pain can lead to the erroneous interpretation that this is a typical trigeminal neuralgia. The lack of its recognition as a side effect of VNS can lead to unnecessary examinations and delayed adjustment of stimulation parameters. In patients with signs of late-onset trigeminal pain under VNS with normal electrode impedance and no evidence of local current spread, the replacement of the VNS lead does not seem to be beneficial. A review of the literature on VNS side effects including pain and device malfunctions was undertaken.
迷走神经刺激术（VNS）用于治疗难治性癫痫已得到充分确立。三叉神经痛本身是成年人的常见疾病，因此，VNS 治疗下三叉神经区域出现的迟发性疼痛极为罕见，可能未被认为是由 VNS 引起的。
两名接受慢性 VNS 治疗的耐药症状性癫痫患者在刺激侧的下颌、上颌和牙齿出现了与刺激相关的疼痛。没有刺激电流局部扩散的证据。疼痛在设备植入数年及起搏参数最后一次增加数周后开始出现。疼痛发作时，未被认为与 VNS 相关，导致进行了广泛检查。调整刺激电流强度后，三叉神经痛样疼痛得到缓解。在其中一名患者中，每次癫痫发作后一到两天内疼痛消失。据我们所知，这是首例关于 VNS 治疗下迟发性三叉神经痛揭示致痫过程与疼痛过程之间直接联系的病例报告。
起搏参数最后一次改变与三叉神经痛之间无痛间期可能导致错误地认为这是典型的三叉神经痛。未将其识别为 VNS 的副作用可能导致不必要的检查和刺激参数调整延迟。对于 VNS 治疗下出现迟发性三叉神经痛体征、电极阻抗正常且无局部电流扩散证据的患者，更换 VNS 导线似乎并无益处。对包括疼痛和设备故障在内的 VNS 副作用的文献进行了综述。
