Is the use of Stereotactic Electroencephalography Safe and Effective in Children? A Meta-Analysis of the use of Stereotactic Electroencephalography in Comparison to Subdural Grids for Invasive Epilepsy Monitoring in Pediatric Subjects

REVIEW Matthew F. Sacino, MD∗ Sean S. Huang, PhD‡ John Schreiber, MD§ William D. Gaillard, MD§ Chima O. Oluigbo, MD∗ ∗ Department of Neurosurgery, Children’s National Medical Center, George Washington University, Washington, District of Columbia; ‡ Department of Health Systems Administration, Georgetown University, Washington, District of Columbia; § Department of Neurology, Children’s National Medical Center, George Washington University, Washington, District of Columbia Correspondence: Chima O. Oluigbo, MD, Departments of Neurosurgery, Children’s National Medical Center, 111 Michigan Avenue NW, Washington, DC 20010. E-mail: Received, December 4, 2017. Accepted, November 9, 2018. Published Online, October 22, 2018. Published by Oxford University Press on behalf of Congress of Neurological Surgeons 2018. This work is written by (a) US Government employee(s) and is in the public domain in the US. BACKGROUND: Stereoelectroencephalography (SEEG) is an alternative addition to subdural grids (SDG) in invasive extra-operative monitoring for medically refractory epilepsy. Few studies exist on the clinical efficacy and safety of these techniques in pediatric populations. OBJECTIVE: To provide a comparative quantitative summary of surgical complications and postoperative seizure freedom associated with invasive extra-operative presurgical techniques in pediatric patients. METHODS: The systematic review was conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). A literature search was conducted utilizing Ovid Medline, Embase, Pubmed, and the Cochrane database. RESULTS: Fourteen papers with a total of 697 pediatric patients undergoing invasive SDG monitoring and 9 papers with a total of 277 pediatric patients undergoing SEEG monitoring were utilized in the systemic review. Cerebral spinal fluid (CSF) leaks were the most common adverse event in the SDG studies (pooled prevalence 11.9% 95% confidence interval [CI] 5.7-23.3). There was one case of CSF leak in the SEEG studies. Intracranial hemorrhages (SDG: 10.7%, 95% CI 5.3-20.3; SEEG: 2.9%, 95% CI –0.7 to 10.8) and infection (SDG: 10.8%, 95% CI 6.7-17) were more common in the SDG studies reviewed. At the time of the last postoperative visit, a greater percentage of pediatric patients achieved seizure freedom in the SEEG studies (SEEG: 66.5%, 95% CI 58.8-73.4; SDG: 52.1%, 95% CI 43.0-61.1). CONCLUSION: SEEG is a safe alternative to SDG and should be considered on an individual basis for selected pediatric patients. KEY WORDS: SEEG, Pediatric, Epilepsy, Invasive monitoring Neurosurgery 84:1190–1200, 2019 S DOI:10.1093/neuros/nyy466 urgery is a proven paradigm for pediatric patients with medically refractory epilepsy, and children are being referred to epilepsy centers for surgical evaluation with increased frequency.1 Standard preoperative assessment includes noninvasive techniques such as magnetic resonance imaging (MRI), video- www.neurosurgery-online.com scalp electroencephalography (video-EEG), functional neuroimaging, magnetoencephalography, and neuropsychological testing.2-4 Indications for invasive intracranial monitoring include nonlesional MRI, need to map eloquent cortex in relation to the epileptic zone, suspicion of extralesional involvement, and failed prior ABBREVIATIONS: CI, confidence interval; CMA, Comprehensive Meta-Analysis; CSF, cerebral spinal fluid; CT, computed tomography; EEG, electroencephalography; ICH, intracranial hematoma; MRI, magnetic resonance imaging; PRISMA, Preferred Reporting Items for Systematic Reviews and Meta-Analyses; SDG, subdural grid; SEEG, stereoelectroencephalography Supplemental digital content is available for this article at www.neurosurgery-online.com. 1190 | VOLUME 84 | NUMBER 6 | JUNE 2019 www.neurosurgery-online.com Is the use of Stereotactic Electroencephalography Safe and Effective in Children? A Meta-Analysis of the use of Stereotactic Electroencephalography in Comparison to Subdural Grids for Invasive Epilepsy Monitoring in Pediatric Subjects META-ANALYSIS: SEEG IN PEDIATRIC EPILEPSY SURGERY METHODS Literature Search The systemic review was conducted in accordance with the Preferred Reporting Items for Systemic Reviews and Meta-analysis (PRISMA; Figure, Supplemental Digital Content 1). A literature search was conducted utilizing Ovid Medline, Embase, Pubmed, and the Cochrane database. Medline and Embase were the primary databases accessed. Pubmed was utilized to find additional literature and to ensure no studies were missed. To assess for SDG electrode studies, in the searching process, we utilized the keywords “subdural” OR “EEG” OR “electroencephalography” OR “invasive monitoring” OR “grid” AND (“surgery” OR “neurosurgery”) AND (“epilepsy” OR “epileptic”; Appendix, Supplemental Digital Content 2). To assess for SEEG studies, we searched utilizing keywords “SEEG” OR “stereoelectroencephalography” OR “stereo” OR “stereo AND electroencephalography” AND (“epilepsy” OR “epileptic”; Appendix, Supplemental Digital Content 3). Our search was limited to English language and human studies. No other restrictions were used. Our initial search concluded on May 17, 2017. Articles were included in our analysis if they met inclusion criteria: (i) pediatric (aged 18 yr or younger), (ii) clear reporting of the presence or absence of complications, (iii) seizure outcomes reported utilizing Engel classification system if resective surgery followed invasive monitoring.7 Study Selection, Data Extraction, and Assessment of Bias Initial screening was performed by one author (MS). Duplicates were discarded and remaining articles were screened by title and abstract. Full texts were then reviewed by 2 authors (MS and CO) for inclusion criteria. Mixed aged studies were only included if the pediatric specific cases were NEUROSURGERY detailed with regard to demographics, postoperative complications, and seizure freedoms. After selecting for included studies, data were extracted by 2 independent reviewers (MS and CO) into separate Microsoft Excel spreadsheets and confirmed for accuracy (Microsoft Excel 2016; Microsoft Corp, Redmond, Washington). The following data were obtained: study design (author, year, prospective or retrospective), study population (age, gender ratio, number of patients undergoing invasive monitoring and resective surgery), number of electrodes utilized, duration of monitoring, medical complications (cerebral spinal fluid [CSF] leaks, hemorrhage, infection [notably meningitis, superficial wound, and osteomyelitis], or cerebral edema), Engel classification at the last postoperative visit, neurological morbidity (hemiparesis, visual field defects, dysphagia, or cranial nerve defects), and mortality. We assessed the risk of bias in the primary studies utilized for our systemic review through the bias domains based on the guidelines of the Cochrane Collaboration’s tool for assessing risk of bias.8 The domains that were rele (...truncated)