Cossu Massimo, Mirandola Laura, Tassi Laura
Epilepsy Surgery Center, Department of Neuroscience, Niguarda Hospital, Piazza Ospedale Maggiore 3, 20162 Milan, Italy.
Epilepsy Res. 2018 May;142:121-125. doi: 10.1016/j.eplepsyres.2017.07.001. Epub 2017 Jul 3.
Drug-resistant focal epilepsy is a common occurrence in patients with gray matter nodular heterotopia (NH), and surgical treatment is often considered in these cases. NH-related epileptogenicity is sustained by complex networks, which may involve the nodules and extralesional cortex in various combinations. Therefore, invasive EEG is usually required to identify the structures involved in seizure generation. It has been reported that surgery may be effective in cases with unilateral lesions, whereas bilateral cases are not optimal candidates for surgical success. Furthermore, violation of cortical and subcortical structures for approaching deep-seated nodules may result in neurological deficits. For these reasons, selective stereotactic ablation with radiofrequency thermocoagulation (RFTC) has been proposed as an alternative option in these patients. In particular, RFTC may be performed by using the same recording intracerebral electrodes implanted for stereo-electro-encephalo-graphy (SEEG) monitoring, with the advantage of a reliable electro-clinical guide. Excellent results on seizures have been initially reported following coagulation of single, unilateral NH. Subsequent experience has indicated that, basing on the evidence of SEEG recording, promising results may be obtained also in more extended unilateral and bilateral cases. In more complex cases, coagulation of both the nodules and of the involved extralesional cortical structures is often required. In a recently reported series, 67% of patients experienced sustained seizure freedom after the procedure. However, post RFTC seizure outcome in complex cases (NH plus other malformations of cortical development) is not as good as in other patterns of NH. RFTC, especially if guided by SEEG evaluation, should be considered as a first-line treatment option in NH-related epilepsy. Satisfactory results may be obtained also in cases not amenable to traditional surgery. The procedure is safe and does not prevent eventual resective surgery in case of failure in seizure control. For these reasons, in patients undergoing SEEG evaluation, electrode arrangement should be planned with the aim to cover as extensively as possible the heterotopic and extralesional areas, which will presumably be the targets of RFTC.
耐药性局灶性癫痫在灰质结节性异位症（NH）患者中很常见，这些病例通常会考虑手术治疗。NH相关的致痫性由复杂网络维持，这些网络可能以各种组合方式涉及结节和病灶外皮质。因此，通常需要进行侵入性脑电图检查以确定癫痫发作产生所涉及的结构。据报道，手术在单侧病变的病例中可能有效，而双侧病例并非手术成功的最佳候选者。此外，为接近深部结节而侵犯皮质和皮质下结构可能导致神经功能缺损。出于这些原因，有人提出使用射频热凝术（RFTC）进行选择性立体定向消融作为这些患者的替代选择。特别是，RFTC可以通过使用为立体脑电图（SEEG）监测而植入的相同记录脑内电极来进行，具有可靠的电临床指导优势。最初报道在对单个单侧NH进行凝固后癫痫发作取得了优异结果。随后的经验表明，基于SEEG记录的证据，在更广泛的单侧和双侧病例中也可能获得良好结果。在更复杂的病例中，通常需要对结节和受累的病灶外皮质结构进行凝固。在最近报道的一组病例中，67%的患者术后癫痫持续缓解。然而，复杂病例（NH加其他皮质发育畸形）的RFTC术后癫痫发作结果不如其他NH模式。RFTC，特别是在SEEG评估指导下，应被视为NH相关癫痫的一线治疗选择。在不适合传统手术的病例中也可能获得满意结果。该手术是安全的，并且在癫痫控制失败的情况下不妨碍最终的切除手术。出于这些原因，在接受SEEG评估的患者中，电极布置应计划为尽可能广泛地覆盖异位和病灶外区域，这些区域可能是RFTC的目标。
