Abstract: Objective To explore the feasibility and application value of radiofrequency thermocoagulation ablation (RF-TC) guided by stereoencephalogram (SEEG) in patients with drug-refractory focal epilepsy. Methods A retrospective analysis was conducted on the clinical data of 32 patients with drug-resistant focal epilepsy who underwent SEEG-guided RF-TC treatment in the Department of Neurosurgery,No 988th Hospital of the PLA Joint Logistics Support Force from January 2018 to June 2024.Comprehensive analysis of symptomatology,electroencephalography (EEG),and imaging data was performed.Based on the anatomo-electro-clinical correlations,a hypothesis regarding the origin of abnormal discharges and the epileptic propagation network was proposed.SEEG electrodes were implanted into relevant brain regions within the epileptic network.The origin of abnormal discharges was identified through SEEG monitoring,and exploratory RF-TC treatment was performed.Treatment efficacy was evaluated by Engel grade. Results All 32 patients had SEEG electrodes accurately implanted into the intended targets.The first 3 cases were implanted using Leksell stereotactic head frame,while the remaining 29 cases were implanted with the guidance of the Sino-Plan neurosurgical robot.Among them,one patient with two electrode implantation and RF-TC.Unilateral electrode implantation was performed in 8 cases(3 on the left side and 5 on the right side),and bilateral implantation was performed in 24 patients.A total of 168 electrodes were implanted,with an average of (5.25±1.3) electrodes per patient(range:3～8).The average SEEG monitoringduration was (9.5±2.4) days (range:5～14days).during which 3～20 habitual seizures were captured in all patients.Cortical electrical stimulation induced habitual seizures in 17 cases,non-habitual seizures in 6 cases.and failed to induce seizures in 9 cases.The epileptogenic zone was successfully identified in all cases,including 15 in the temporal lobe,12 in the frontal lobe,3 in the occipital lobe,and 1 case in parietal lobe,1 case in insula lobe.RF-TC was performed using 2～5 electrodes,with an average of (3.1±1.6)electrodes,.There are 12～38 radiofrequency thermocoagulation contacts,with an average of (20.1±4.5)contacts.Post-RF-TC complications included headache in 13 cases,severe cerebral edema with encapsulated effusion resulting transient contralateral upper limb weakness and reduced dexterity in 1case,and temporary behavior abnormalities in 1 case.No complications such as intracranial infection,cerebrospinal fluid leakage,or severe neurological deficits occurred.The follow-up period was (12.9±16.6) months (range:5～78 months).After RF-TC,1 patient achieved Engel Class I,while 31 cases experienced recurrences of varying degrees and durations,including 2 cases within 2 weeks,5 cases within 1 month,and 24 cases within 1～3 months.Subsequently,19 cases underwent elective craniotomy for resection of the epileptogenic zone,resulting in 17 cases(89.47%) achieving Engel Class I and 2 cases(10.53%) achieving Engel Class II.At the final follow-up,the overall efficacy assessment showed 18 cases (56.25%) in Engel Class I,8 cases (25%) in Engel Class II,and 6 cases (18.75%) in Engel Class III. Conclusion SEEG-guided RF-TC can promptly and effectively alleviate epileptic seizures to varying degrees,guide subsequent craniotomy for the resection of the epileptogenic zone,and predict surgical outcomes.It holds significant application value in the surgical treatment of drug-resistant focal epilepsy.

Key words: Focal epilepsy, Epileptogenic zone, Stereoelectroencephalography, Radiofrequency thermocoagulation, Electrical cortical stimulation

摘要： 目的 探讨立体脑电图(SEEG)引导下射频热凝毁损术(RF-TC)在药物难治性局灶性癫痫患者中的可行性、应用价值。方法 回顾性分析2018年1月至2024年6月中国人民解放军联勤保障部队第九八八医院神经外科行SEEG引导下RF-TC治疗的32例药物难治性局灶性癫痫患者的临床资料,综合分析症状学、脑电图、影像学资料,依据解剖-电-临床症状,提出异常放电起源和癫痫扩散网络的核心假设,将SEEG电极置入癫痫网络的相关脑区,SEEG监测判断异常放电起源点,进行探索性RF-TC治疗,采用Engel分级评估疗效。结果 32例患者均准确置入SEEG电极至预期靶点,前3例采用Leksell立体定向仪引导下置入,后29例采用Sino-Plan神经外科手术机器人引导下置入,其中先后两次电极置入并RF-TC 1例。单侧电极置入8例,其中左侧3例,右侧5例;双侧电极置入24例。共置入电极168根,平均(5.2±1.3)根(3～8根)。SEEG监测时间平均(9.5±2.4)d(5～14d),均捕捉到3～20次惯常发作。皮质电刺激诱发出惯常发作17例,非惯常发作6例,未能诱发出发作9例。均能明确致痫区,其中颞叶15例、额叶12例,枕叶3例,顶叶及岛叶各1例。应用射频热凝电极2～5根,平均(3.1±1.6)根,热凝触点12～38个,平均(20.1±4.5)个。RF-TC后头痛13例、严重脑水肿并形成包裹性积液致对侧上肢短期无力、活动不灵活1例,暂时性行为异常1例,无颅内感染、脑脊液漏及严重神经功能损害等并发症发生。随访时间为(12.9±16.6)个月(5～78个月),RF-TC 后,Engel I 级1例,不同程度及时限内复发31例,其中2周内复发2例、1个月内复发5例、1～3个月内复发24例;后续择期开颅切除致痫区19例,切除术后Engel I 级17例(89.47%),Engel II 级2例(10.53%)。末次随访时总体疗效评估,Engel I 级18例(56.25%),Engel II 级8例(25%),Ш级6例(18.75%)。结论 SEEG引导下RF-TC 可不同程度及时缓解癫痫发作,指导后续开颅手术切除致痫区,并能预测手术效果,在药物难治性局灶性癫痫的手术治疗中有一定的应用价值。

关键词: 局灶性癫痫, 致痫区, 立体脑电图, 射频热凝毁损, 皮质电刺激