Ko D, Heck C, Grafton S, Apuzzo M L, Couldwell W T, Chen T, Day J D, Zelman V, Smith T, DeGiorgio C M
Department of Neurology, University of Southern California, Los Angeles, USA.
Neurosurgery. 1996 Aug;39(2):426-30; discussion 430-1. doi: 10.1097/00006123-199608000-00061.
To determine the central areas of activation by vagal nerve stimulation (VNS) in epilepsy. VNS is a promising neurosurgical method for treating patients with partial and secondary generalized epilepsy. The anti-epileptic mechanism of action from VNS is not well understood.
We performed H2(15)O PET blood flow functional imaging on three patients with epilepsy in a vagal nerve stimulation study (E04 Protocol with Cyberonics). The three patients included two that had previous epilepsy surgery but continued to have frequent seizures. Seizure onset was frontal in two patients and bitemporal in the third patient. Twelve PET scans per subject were acquired every 10 minutes with a Siemens 953/A scanner. In 6 stimulus scans, VNS was activated for 60 seconds (2 mA, 30 Hz) commensurate with isotope injection. In 6 control scans no VNS was administered. No clinical seizures were present during any scan. Three way ANOVA with linear contrasts subject, task, repetition) of coregistered images identified significant treatment effects.
The difference between PET with VNS and without revealed that left VNS activated right thalamus (P < 0.0006), right posterior temporal cortex (P < 0.0003), left putamen (P < 0.0002), and left inferior cerebellum (P < 0.0009).
VNS causes activation of several central areas including contralateral thalamus. Localization to the thalamus suggests a possible mechanism to explain the therapeutic benefit, consistent with the role of the thalamus as a generator and modulator of cerebral activity.
确定癫痫患者经迷走神经刺激（VNS）后的中枢激活区域。VNS是一种治疗部分性和继发性全身性癫痫患者的有前景的神经外科方法。VNS的抗癫痫作用机制尚不完全清楚。
我们对三名癫痫患者进行了H2(15)O PET血流功能成像，以进行迷走神经刺激研究（采用Cyberonics公司的E04方案）。这三名患者中，两名曾接受过癫痫手术，但仍频繁发作。两名患者的癫痫发作起始于额叶，第三名患者的发作起始于双侧颞叶。使用西门子953/A扫描仪，每10分钟为每位受试者采集12次PET扫描。在6次刺激扫描中，VNS在与同位素注射同步时激活60秒（2毫安，30赫兹）。在6次对照扫描中未进行VNS刺激。在任何扫描过程中均未出现临床癫痫发作。对配准图像进行三因素方差分析（受试者、任务、重复），确定了显著的治疗效果。
VNS与无VNS状态下的PET差异显示，左侧VNS激活了右侧丘脑（P < 0.0006）、右侧颞叶后皮质（P < 0.0003）、左侧壳核（P < 0.0002）和左侧小脑下部（P < 0.0009）。
VNS可导致包括对侧丘脑在内的多个中枢区域激活。定位于丘脑提示了一种可能解释治疗益处的机制，这与丘脑作为大脑活动的发生器和调节器的作用相一致。
