立体定向脑电图证实的岛叶癫痫手术疗效分析

 目的 探讨经立体定向脑电图（stereoelectroencephalography,SEEG）证实为岛叶起源的难治性癫痫的手术疗效。方法 选取2017年4月至2020年10月上海德济医院癫痫中心行SEEG监测明确为岛叶起源的难治性癫痫病例11例,回顾性分析其临床资料（症状学、头皮脑电图、影像学、SEEG结果、术后病理学诊断以及术后癫痫控制情况等）,评估并探讨岛叶起源的难治性癫痫的外科手术疗效。结果 11例患者共植入电极148根,其中岛叶电极69根,未出现电极相关并发症。所有患者均按照个体化手术方案行致痫灶切除,随访时间6~42个月。术后9例患者无癫痫发作（Engel Ⅰ级）,1例仅有轻型发作（Engel Ⅱ级）,1例仍有癫痫频繁发作（Engel Ⅳ级）。组织病理学诊断：神经胶质增生6例,灶性软化3例,结节性硬化1例,炎症1例（脑膜炎病史）。术后2例患者出现不同程度的对侧肢体偏瘫,1例患者出现混合性失语,1例剧烈呕吐,1例颅内感染。上述除1例患者出现永久性一侧肢体轻瘫外,其余病例均于1个月内恢复正常。结论 经SEEG监测明确为岛叶起源的难治性癫痫经临床评估后可行外科手术切除治疗者,多能够获得较为满意的癫痫控制结果。     

Evolution of pediatric epilepsy surgery program over 2000–2017: Improvement of care?

PurposeWe assessed trends in spectrum of candidates, diagnostic algorithm, therapeutic approach and outcome of a pediatric epilepsy surgery program between 2000 and 2017.MethodsAll pediatric patients who underwent curative epilepsy surgery in Motol Epilepsy Center during selected period (n = 233) were included in the study and divided into two groups according to time of the surgery (developing program 2000–2010: n = 86, established program 2011–2017: n = 147). Differences in presurgical, surgical and outcome variables between the groups were statistically analyzed.ResultsA total of 264 resections or hemispheric disconnections were performed (including 31 reoperations). In the later epoch median age of candidates decreased. Median duration of disease shortened in patients with temporal lobe epilepsy. Number of patients with non-localizing MRI findings (subtle or multiple lesions) rose, as well as those with epileptogenic zone adjacent to eloquent cortex. There was a trend towards one-step procedures guided by multimodal neuroimaging and intraoperative electrophysiology; long-term invasive EEG was performed in fewer patients. Subdural electrodes for long-term invasive monitoring were almost completely replaced by stereo-EEG. The number of focal resections and hemispherotomies rose over time. Surgeries were more often regarded complete. Histopathological findings of resected tissue documented developing spectrum of candidates. 82.0% of all children were seizure-free two years after surgery; major complications occurred in 4.6% procedures; both groups did not significantly differ in these parameters.ConclusionIn the established pediatric epilepsy surgery program, our patients underwent epilepsy surgery at younger age and suffered from more complex structural pathology. Outcomes and including complication rate remained stable.     

Sleep modulates effective connectivity: A study using intracranial stimulation and recording

ObjectiveSleep is an active process with an important role in memory. Epilepsy patients often display a disturbed sleep architecture, with consequences on cognition. We aimed to investigate the effect of sleep on cortical networks’ organization.MethodsWe analyzed cortico-cortical evoked responses elicited by single pulse electrical stimulation (SPES) using intracranial depth electrodes in 25 patients with drug-resistant focal epilepsy explored using stereo-EEG. We applied the SPES protocol during wakefulness and NREM – N2 sleep. We analyzed 31,710 significant responses elicited by 799 stimulations covering most brain structures, epileptogenic or non-epileptogenic. We analyzed effective connectivity between structures using a graph-theory approach.ResultsSleep increases excitability in the brain, regardless of epileptogenicity. Local and distant connections are differently modulated by sleep, depending on the tissue epileptogenicity.In non-epileptogenic areas, frontal lobe connectivity is enhanced during sleep. There is increased connectivity between the hippocampus and temporal neocortex, while perisylvian structures are disconnected from the temporal lobe. In epileptogenic areas, we found a clear interhemispheric difference, with decreased connectivity in the right hemisphere during sleep.ConclusionsSleep modulates brain excitability and reconfigures functional brain networks, depending on tissue epileptogenicity.SignificanceWe found specific patterns of information flow during sleep in physiologic and pathologic structures, with possible implications for cognition.     

Epileptogenic network of focal epilepsies mapped with cortico-cortical evoked potentials

ObjectiveThe goal of this study was to investigate the spatial extent and functional organization of the epileptogenic network through cortico-cortical evoked potentials (CCEPs) in patients being evaluated with intracranial stereoelectroencephalography.MethodsWe retrospectively included 25 patients. We divided the recorded sites into three regions: epileptogenic zone (EZ); propagation zone (PZ); and noninvolved zone (NIZ). The root mean square of the amplitudes was calculated to reconstruct effective connectivity network. We also analyzed the N1/N2 amplitudes to explore the responsiveness influenced by epileptogenicity. Prognostic analysis was performed by comparing intra-region and inter-region connectivity between seizure-free and non-seizure-free groups.ResultsOur results confirmed that stimulation of the EZ caused the strongest responses on other sites within and outside the EZ. Moreover, we found a hierarchical connectivity pattern showing the highest connectivity strength within EZ, and decreasing connectivity gradient from EZ, PZ to NIZ. Prognostic analysis indicated a stronger intra-EZ connection in the seizure-free group.ConclusionThe EZ showed highest excitability and dominantly influenced other regions. Quantitative CCEPs can be useful in mapping epileptic networks and predicting surgical outcome.SignificanceThe generated computational connectivity model may enhance our understanding of epileptogenic networks and provide useful information for surgical planning and prognosis prediction.     

“Plok-plok” syndrome: Posttraumatic stress disorder following an SEEG thermocoagulation and direct electrical stimulation procedure

The psychological impact of intracerebral electroencephalography (stereoelectroencephalography [SEEG]) including the thermocoagulation procedure has not yet been clearly studied. We present a case of a patient who, following an SEEG procedure for presurgical evaluation of intractable focal epilepsy, developed severe symptoms of posttraumatic stress disorder. Such an occurrence may be under-estimated. Perceived traumatic exposure during SEEG and the development of posttraumatic psychological symptoms should be further studied in order to define risk factors and to improve the monitoring and psychological management of patients during their hospitalization. A careful and systematic procedure of prevention and support before, during, and after SEEG could decrease the risk of development or worsening of symptoms of anxiety, depression, and posttraumatic stress disorder.     

Robot-assisted versus stereotactic frame-based stereoelectroencephalography in medically refractory epilepsy

AimTo explore the difference between robot assisted (RA) and stereotactic frame based (SF) stereoelectroencephalography (SEEG) in patients with medically refractory epilepsy.MethodsWe undertook a retrospective review of 33 SEEG cases at our center, of which 14 were SF performed from March to October 2018 and 19 were RA performed from November 2018 to December 2019. Detailed review of medical histories and operative records as well as imaging and trajectory plans was carried out for each patient, and the results related to each technique compared. A multiple linear regression model was used to test for variables that significantly influenced placement error.ResultsCompared to the SF group, the RA group had a higher mean number of electrodes per patient (10.7 ± 2.8 versus 6.4 ± 0.8, P < 0.0001) and a significantly shorter mean operative time (127.3 ± 40.7 versus 152.7 ± 13.6 min, P = 0.033). For the RA group, the intracranial implantation length was positively correlated with target point error (p = 0.000), depth error (p = 0.043), and two-dimensional (2D) radial error (p = 0.041). Conversely, skull thickness was negatively correlated with the TP error (p = 0.004), depth error (p = 0.037) and 2D radial error (p = 0.000). We also analyzed the mean entry point, target point, depth and 2D radial errors, the complication rates, and the results of epileptogenic zone (EZ) localization and Engel class. The results showed no difference in these aspects between the SF group and the RA group.ConclusionThis study suggests that, compared to stereotactic frame based SEEG, robot assisted SEEG is significantly more efficient and comparable in safety and effectiveness.     

Interictal ripples nested in epileptiform discharge help to identify the epileptogenic zone in neocortical epilepsy

Objective

This study aimed to identify the subtype of interictal ripples that help delineate the epileptogenic zone in neocortical epilepsy.

立体定向脑电图在药物难治性癫术前侵袭性评估中的应用价值和安全性

目的 探讨立体定向脑电图（SEEG）在药物难治性癫（DRE）术前侵袭性评估中的应用价值和安全性。方法 回顾性分析2016年8月至2018年11月在深圳市第二人民医院和深圳大学总医院开展SEEG置入的DRE患者的临床资料。根据患者无创的评估检查,提出可疑致灶位置和传播路径的假设,制定SEEG置入方案,最后根据SEEG和电刺激结果,制定最终手术切除或射频热凝方案,完成外科手术。结果 31例DRE患者共成功置入电极359根电极,平均11.58根/人,电极置入失败13根（3.62%）,无追加电极置入情况。术后出现迟发性颅内出血1例,未出现颅内感染、脑脊液漏等并发症。SEEG置入后,20例患者行致灶切除,8例患者行致网络射频热凝术,1例致灶位于功能区行迷走神经刺激术,2例患者未行手术治疗。31例患者随访时间为6~30个月,平均为（11.68±7.46）个月。20例行致灶切除术患者术后国际抗癫联盟（ILAE）分级Ⅰ级17例（85.00%,17/20）、Ⅱ级2例（10.00%,2/20）、Ⅲ级1例（5.00%,1/20）,8例行致网络射频热凝术患者术后ILAE Ⅰ级6例（75.00%,6/8）、Ⅲ级2例（25.00%,2/8）,2种不同治疗手段间的疗效差异无统计学意义（P=0.61）。13例磁共振成像（MRI）阴性患者中术后ILAE Ⅰ级10例（76.92%,10/13）、Ⅱ级2例（15.38%,2/13）、Ⅲ级1例（7.69%,1/13）,15例MRI阳性患者中术后ILAE Ⅰ级13例（86.67%,13/15）、Ⅲ级2例（13.33%,2/15）,两者间疗效差异无统计学意义（P=0.64）。结论 无论是MRI阳性还是MRI阴性的DRE病例,SEEG均可以提高致灶定位的精准性,SEEG指导下外科治疗DRE是安全、有效的。