Ragazzo P C, Galanopoulou A S
Epilepsy Surgery Unit, Instituto de Neurologia de Goiania, Goias, 74, 000, Brazil.
Brain Res Brain Res Rev. 2000 Apr;32(1):316-27. doi: 10.1016/s0165-0173(99)00098-3.
Pharmacologic activation of epileptic foci has been used experimentally with the hope that it may accelerate the presurgical evaluation of patients with medically intractable epilepsy. In this article, we will review the existing literature on these activating tests giving emphasis on the opioid analogs, and particularly alfentanil. Alfentanil is an opioid analog with rapid anesthetic effect, which has been known to trigger epileptiform discharges in epilepsy patients. 58 temporal lobe epilepsy (TLE) patients were studied with alfentanil activation during electrocorticography, at the Epilepsy Surgery Unit (ING, Brazil). An increase of the interictal epileptiform discharges was observed originating from hippocampal and parahippocampal regions (96.5%). To a lesser extent, alfentanil activated the basal and lateral temporal regions. Electrographic seizures were observed in 38%. In addition, we performed continuous video-EEG (VT/EEG) monitoring, with scalp and bilateral foramen ovale electrodes, in 12 TLE patients. The results of spontaneously observed seizures were compared with the electrographic changes following alfentanil activation (50-75 microg/kg, i.v.). In seven cases, alfentanil triggered focal electrographic seizures, ipsilaterally to the side generating the spontaneous seizures and in two patients it produced bilateral sequential activation of the temporal lobes. Ictal SPECTs during the alfentanil test showed hyperperfusion at the lateral temporal regions, ipsilaterally to the activated area or bilaterally. In summary, our study confirms the activating effect of alfentanil, and provides a strong evidence for its selective activating effect on the temporal lobes of TLE patients. The ictal SPECT during alfentanil activation did not offer any additional advantage for the localization of the ictal onset.
癫痫病灶的药理学激活已在实验中使用，希望它能加速药物难治性癫痫患者的术前评估。在本文中，我们将回顾关于这些激活试验的现有文献，重点关注阿片类类似物，特别是阿芬太尼。阿芬太尼是一种具有快速麻醉作用的阿片类类似物，已知它会在癫痫患者中引发癫痫样放电。在巴西癫痫手术单元（ING），对58例颞叶癫痫（TLE）患者在皮质脑电图监测期间进行了阿芬太尼激活研究。观察到发作间期癫痫样放电增加，起源于海马和海马旁区域（96.5%）。在较小程度上，阿芬太尼激活了颞叶基底和外侧区域。38%的患者观察到脑电图发作。此外，我们对12例TLE患者进行了连续视频脑电图（VT/EEG）监测，使用头皮电极和双侧卵圆孔电极。将自发观察到的发作结果与阿芬太尼激活（静脉注射50 - 75微克/千克）后的脑电图变化进行比较。在7例患者中，阿芬太尼引发了局灶性脑电图发作，与产生自发发作的一侧同侧，在2例患者中它导致了颞叶的双侧顺序激活。阿芬太尼试验期间的发作期单光子发射计算机断层扫描（SPECT）显示，在激活区域同侧或双侧的颞叶外侧区域有血流灌注增加。总之，我们的研究证实了阿芬太尼的激活作用，并为其对TLE患者颞叶的选择性激活作用提供了有力证据。阿芬太尼激活期间的发作期SPECT在发作起始定位方面没有提供任何额外优势。
