Supplementary Material for: Peri-Insular hemispherotomy: A systematic review and institutional experience

Purpose: Peri-insular hemispherotomy (PIH) is a hemispheric separation technique under the broader hemispherotomy group, a surgical treatment for patients with intractable epilepsy. Hemispherotomy techniques such as the PIH, vertical parasagittal hemispherotomy (VPH), and modified-lateral hemispherotomy are commonly assessed together, despite significant differences in anatomical approach and patient selection. We aim to describe patient selection, outcomes, and complications of PIH in its own right. Methods: A systematic review of the literature, in accordance with the Preferred Reporting Items of Systematic Reviews and Meta-Analyses (PRISMA) guidelines was conducted, with searches of the PUBMED and EMBASE databases. A local series including patients receiving PIH and followed-up at the Queensland Children’s Hospital between 2014 – 2020 was included. Results: Systematic review of the literature identified 393 patients from 13 eligible studies. Engel Class I outcomes occurred in 82.4% of patients, while 8.6% developed post-operative hydrocephalus. Hydrocephalus was most common in the youngest patient cohorts. Developmental pathology was present in 114 (40.8%) patients, who had fewer Engel I outcomes compared to those with acquired pathology (69.1% versus 83.7%, p = 0.0167). The local series included 13 patients, 11/13 (84.6%) had Engel Class I seizure outcomes. Post-operative hydrocephalus occurred in 2 patients (15.4%), and 10/13 (76.9%) patients had worsened neurological deficit. Conclusion: PIH delivers Engel I outcomes for over 4 in 5 patients selected for this procedure, greater than described in combined hemispherectomy analyses. It is an effective technique in patients with developmental and acquired pathologies, despite general preference of VPH in this patient group. Finally, very young patients may have significant seizure and cognitive benefits from PIH, however hydrocephalus is most common in this group warranting careful risk-benefit assessment. This review delivers a dedicated PIH outcomes analysis to inform clinical and patient decision making.一、研究目的：围岛叶半球离断术（Peri-insular Hemispherotomy, PIH）属于更广泛的半球离断术范畴内的半球分离技术，是难治性癫痫患者的手术治疗方案。尽管PIH、垂直矢状旁半球离断术（Vertical Parasagittal Hemispherotomy, VPH）及改良外侧半球离断术等各类半球离断术在解剖入路与患者选择上存在显著差异，但临床通常会将其一同评估。本研究旨在单独阐述PIH的患者选择标准、治疗结局及并发症情况。 二、研究方法：本研究遵循《系统评价与Meta分析首选报告条目》（Preferred Reporting Items for Systematic Reviews and Meta-Analyses, PRISMA）指南，对PubMed及EMBASE数据库开展系统性文献检索，并纳入2014年至2020年间在昆士兰儿童医院接受PIH手术并完成随访的13例患者的本地临床队列数据。 三、研究结果：系统性文献检索共纳入13项符合标准的研究，涉及393例患者。其中82.4%的患者达到Engel I级癫痫发作控制结局，8.6%的患者术后出现脑积水，且脑积水在最年幼的患者队列中最为高发。114例（40.8%）患者存在发育性病理，该亚组的Engel I级结局发生率（69.1%）显著低于获得性病理亚组（83.7%，p=0.0167）。本地队列共纳入13例患者，11/13（84.6%）达到Engel I级癫痫发作控制结局；2例（15.4%）出现术后脑积水，10/13（76.9%）的患者术后神经功能缺损加重。 四、研究结论：本研究结果显示，针对接受PIH手术的患者，超五分之四可达到Engel I级结局，这一比例高于既往联合半球离断术的分析结果。尽管该患者群体通常更倾向于采用VPH手术，但PIH对发育性病理及获得性病理患者均为有效的治疗方案。此外，极低龄患者或可从PIH术中获得显著的癫痫控制与认知获益，但该群体术后脑积水发生率最高，因此需谨慎开展风险-获益评估。本综述首次针对PIH的治疗结局开展专项分析，可为临床决策及患者诊疗选择提供参考依据。