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Shin HJ, Kim SH, Kang HC, Lee JS, Kim HD. Surgical Treatment of Epilepsy with Bilateral MRI Abnormalities. World Neurosurg 2023; 180:e37-e45. [PMID: 37495100 DOI: 10.1016/j.wneu.2023.07.062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Revised: 07/12/2023] [Accepted: 07/13/2023] [Indexed: 07/28/2023]
Abstract
OBJECTIVE To investigate the surgical outcomes of patients with drug-resistant epilepsy and bilateral brain magnetic resonance imaging (MRI) abnormalities who had undergone various epilepsy surgeries. METHODS Patients with drug-resistant epilepsy and bilateral brain abnormalities on MRI who underwent epilepsy surgery at the Severance Children's Hospital between October 2003 and December 2021 were included. The age of seizure onset was 18 years or younger. Engel's classification was used to assess seizure outcomes at 1, 2, and 5 years after surgery. RESULTS A total of 40 patients met the inclusion criteria. The median age at surgery was 10.9 years (interquartile range [IQR] 6.9-15.1); the median interval to surgery was 7.1 years (IQR 2.7-11.5). One year after surgery, a favorable outcome of Engel class I-II was observed in 53% (21/40) of patients. At the 2- and 5-year follow-ups, 56% (20/36) and 63% (17/27) of patients showed good postoperative outcomes, respectively. CONCLUSIONS Approximately, half of the patients with bilateral brain MRI abnormalities achieved seizure freedom after epilepsy surgery. The existence of bilateral brain MRI abnormalities should not hinder resective epilepsy surgery.
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Affiliation(s)
- Hui Jin Shin
- Division of Pediatric Neurology, Department of Pediatrics, Epilepsy Research Institute, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - Se Hee Kim
- Division of Pediatric Neurology, Department of Pediatrics, Epilepsy Research Institute, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - Hoon-Chul Kang
- Division of Pediatric Neurology, Department of Pediatrics, Epilepsy Research Institute, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - Joon Soo Lee
- Division of Pediatric Neurology, Department of Pediatrics, Epilepsy Research Institute, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - Heung Dong Kim
- Division of Pediatric Neurology, Department of Pediatrics, Epilepsy Research Institute, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea; Department of Pediatrics, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
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Reinholdson J, Olsson I, Edelvik Tranberg A, Malmgren K. Low IQ predicts worse long-term seizure outcome after resective epilepsy surgery - A propensity score matched analysis. Epilepsy Res 2023; 191:107110. [PMID: 36821876 DOI: 10.1016/j.eplepsyres.2023.107110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 02/09/2023] [Accepted: 02/13/2023] [Indexed: 02/18/2023]
Abstract
OBJECTIVE To describe long-term seizure outcomes in patients with IQ < 70 undergoing resective epilepsy surgery and to analyse whether baseline IQ predicts seizure outcome. METHODS Patients undergoing focal resective epilepsy surgery 1995-2017 at age ≥ 4 years were identified in the population-based Swedish National Epilepsy Surgery Register. Two-year, five-year and long-term (10-20-year follow-up) outcomes were analysed. Seizure outcomes of patients with IQ ≥ 70 and IQ < 70 at baseline were compared in the full cohort and between propensity score matched groups. RESULTS Follow-up data were available for 884 patients, 79 of whom had IQ < 70. Matched controls were found for 74 of the IQ < 70 patients. Preoperative MRI pathology was unifocal in 54 % and 79 % of IQ < 70 and IQ ≥ 70 patients before matching compared to 58 % and 62 % after matching, respectively. Patients with IQ < 70 achieved significantly worse seizure outcomes at all time points both when analysing the full cohort and the matched groups. After matching, the proportions of seizure-free patients in the IQ < 70 group were 28 %, 32 % and 32 % at the 2-year, 5-year and long-term follow-ups, respectively. Corresponding figures in the IQ ≥ 70 group were 54 %, 62 % and 60 % (p for difference between IQ groups 0.004, 0.002 and 0.049). In the IQ < 70 group, 36 %, 29 % and 45 % had a ≥ 75 % reduction in seizure frequency at the respective three follow-ups. CONCLUSION Low preoperative IQ predicts lower chances of seizure freedom after resective epilepsy surgery and few patients with IQ < 70 remain completely seizure-free in the long term. Nevertheless, a significant proportion had a reduction in seizure frequency of at least 75 % at long-term follow-up, indicating an important palliative potential of resective surgery for epilepsy patients with intellectual disability.
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Affiliation(s)
- Jesper Reinholdson
- Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at Gothenburg University, Gothenburg, Sweden.
| | - Ingrid Olsson
- Department of Paediatrics, Institute of Clinical Sciences, Sahlgrenska Academy at Gothenburg University, Gothenburg, Sweden.
| | - Anna Edelvik Tranberg
- Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at Gothenburg University, Gothenburg, Sweden; Department of Neurology, Sahlgrenska University Hospital, Member of the ERN EpiCARE, SE-413 45 Gothenburg, Sweden..
| | - Kristina Malmgren
- Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at Gothenburg University, Gothenburg, Sweden; Department of Neurology, Sahlgrenska University Hospital, Member of the ERN EpiCARE, SE-413 45 Gothenburg, Sweden..
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Kogias E, Bast T, Schubert-Bast S, Wiegand G, Brandt A, Strobl K, Korinthenberg R, Schulze-Bonhage A, Zentner J, Ramantani G. Multilobar Epilepsy Surgery in Childhood and Adolescence: Predictors of Long-Term Seizure Freedom. Neurosurgery 2020; 88:174-182. [PMID: 32814942 DOI: 10.1093/neuros/nyaa368] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Accepted: 06/18/2020] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Although multilobar resections correspond to one-fifth of pediatric epilepsy surgery, there are little data on long-term seizure control. OBJECTIVE To investigate the long-term seizure outcomes of children and adolescents undergoing multilobar epilepsy surgery and identify their predictors. METHODS In this retrospective study, we considered 69 consecutive patients that underwent multilobar epilepsy surgery at the age of 10.0 ± 5.0 yr (mean ± SD). The magnetic resonance imaging revealed a lesion in all but 2 cases. Resections were temporo-parieto(-occipital) in 30%, temporo-occipital in 41%, parieto-occipital in 16%, and fronto-(temporo)-parietal in 13% cases. Etiologies were determined as focal cortical dysplasia in 67%, perinatal or postnatal ischemic lesions in 23%, and benign tumors in 10% of cases. RESULTS At last follow-up of median 9 yr (range 2.8-14.8), 48% patients were seizure free; 33% were off antiepileptic drugs. 10% of patients, all with dysplastic etiology, required reoperations: 4 of 7 achieved seizure freedom. Seizure recurrence occurred mostly (80%) within the first 6 mo. Among presurgical variables, only an epileptogenic zone far from eloquent cortex independently correlated with significantly higher rates of seizure arrest in multivariate analysis. Among postsurgical variables, the absence of residual lesion and of acute postsurgical seizures was independently associated with significantly higher rates of seizure freedom. CONCLUSION Our study demonstrates that multilobar epilepsy surgery is effective regarding long-term seizure freedom and antiepileptic drug withdrawal in selected pediatric candidates. Epileptogenic zones-and lesions-localized distant from eloquent cortex and, thus, fully resectable predispose for seizure control. Acute postsurgical seizures are critical markers of seizure recurrence that should lead to prompt reevaluation.
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Affiliation(s)
- Evangelos Kogias
- Department of Neurosurgery, University Hospital Freiburg, Freiburg im Breisgau, Germany.,Medical Faculty, University of Freiburg, Freiburg im Breisgau, Germany
| | - Thomas Bast
- Medical Faculty, University of Freiburg, Freiburg im Breisgau, Germany.,Epilepsy Center Kork, Kehl-Kork, Germany
| | - Susanne Schubert-Bast
- Department of General Pediatrics, University Children's Hospital Heidelberg, Heidelberg, Germany.,Department of Neuropediatrics, University Children's Hospital Frankfurt, Frankfurt, Germany.,Epilepsy Center Frankfurt Rhine-Main, Frankfurt am Main, Germany
| | - Gert Wiegand
- Department of Neuropediatrics, University Medical Center Schleswig-Holstein, Kiel, Germany
| | - Armin Brandt
- Epilepsy Center, University Hospital Freiburg, Freiburg im Breisgau, Germany
| | - Karl Strobl
- Medical Faculty, University of Freiburg, Freiburg im Breisgau, Germany
| | - Rudolf Korinthenberg
- Department of Neuropediatrics and Muscular Disorders, University Children's Hospital Freiburg, Freiburg im Breisgau, Germany
| | | | - Josef Zentner
- Department of Neurosurgery, University Hospital Freiburg, Freiburg im Breisgau, Germany
| | - Georgia Ramantani
- Medical Faculty, University of Freiburg, Freiburg im Breisgau, Germany.,Epilepsy Center, University Hospital Freiburg, Freiburg im Breisgau, Germany.,Department of Neuropediatrics, University Children's Hospital Zurich, Zurich, Switzerland
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d'Orio P, Rizzi M, Mariani V, Pelliccia V, Lo Russo G, Cardinale F, Nichelatti M, Nobili L, Cossu M. Surgery in patients with childhood-onset epilepsy: analysis of complications and predictive risk factors for a severely complicated course. J Neurol Neurosurg Psychiatry 2019; 90:84-89. [PMID: 30100551 DOI: 10.1136/jnnp-2018-318282] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Revised: 07/12/2018] [Accepted: 07/15/2018] [Indexed: 11/03/2022]
Abstract
OBJECT To compare the occurrence of surgery-related complications in patients with childhood-onset focal epilepsy operated on in the paediatric or in the adult age. To investigate risk factors for surgery-related complications in the whole cohort, with special attention to age at surgery and severe morbidity. METHODS A cohort of 1282 patients operated on for childhood-onset focal epilepsy was retrospectively analysed. Occurrence of surgery-related complications, including a severely complicated course (SCC: surgical complication requiring reoperation and/or permanent neurological deficit and/or death), was compared between patients operated on in the paediatric age (<16 year-old; 452 cases) and, respectively, in adulthood (≥16 year-old; 830 cases). The whole cohort of patients was also evaluated for risk factors for a SCC. RESULTS At last contact (median follow-up 98 months), 74.5% of patients were in Engel's class I (78.0% of children and 73.0% of adults). One hundred patients (7.8%) presented a SCC (6.4% for children and 8.6% for adult patients). Postoperative intracranial haemorrhages occurred more frequently in adult cases. At multivariate analysis, increasing age at operation, multilobar surgery, resections in the rolandic/perirolandic and in insulo-opercular regions were independent risk factors for a SCC. CONCLUSIONS Surgery for childhood-onset focal epilepsy provides excellent results on seizures and an acceptable safety profile at any age. Nevertheless, our results suggest that increasing age at surgery is associated with an increase in odds of developing severe surgery-related complications. These findings support the recommendation that children with drug-resistant, symptomatic (or presumed symptomatic) focal epilepsy should be referred for a surgical evaluation as early as possible after seizure onset.
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Affiliation(s)
- Piergiorgio d'Orio
- "Claudio Munari" Epilepsy Surgery Centre, Azienda Socio Sanitaria Territoriale Grande Ospedale Metropolitano Niguarda, Milano, Italy
| | - Michele Rizzi
- "Claudio Munari" Epilepsy Surgery Centre, Azienda Socio Sanitaria Territoriale Grande Ospedale Metropolitano Niguarda, Milano, Italy.,Department of Neuroscience, University of Parma, Parma, Italy
| | - Valeria Mariani
- "Claudio Munari" Epilepsy Surgery Centre, Azienda Socio Sanitaria Territoriale Grande Ospedale Metropolitano Niguarda, Milano, Italy
| | - Veronica Pelliccia
- "Claudio Munari" Epilepsy Surgery Centre, Azienda Socio Sanitaria Territoriale Grande Ospedale Metropolitano Niguarda, Milano, Italy
| | - Giorgio Lo Russo
- "Claudio Munari" Epilepsy Surgery Centre, Azienda Socio Sanitaria Territoriale Grande Ospedale Metropolitano Niguarda, Milano, Italy
| | - Francesco Cardinale
- "Claudio Munari" Epilepsy Surgery Centre, Azienda Socio Sanitaria Territoriale Grande Ospedale Metropolitano Niguarda, Milano, Italy
| | - Michele Nichelatti
- Service of Biostatistics, Azienda Socio Sanitaria Territoriale Grande Ospedale Metropolitano Niguarda, Milano, Italy
| | - Lino Nobili
- "Claudio Munari" Epilepsy Surgery Centre, Azienda Socio Sanitaria Territoriale Grande Ospedale Metropolitano Niguarda, Milano, Italy.,Child Neuropsychiatry Unit, DINOGMI, University of Genoa, Genoa, Italy, Istituto Giannina Gaslini, Genova, Italy
| | - Massimo Cossu
- "Claudio Munari" Epilepsy Surgery Centre, Azienda Socio Sanitaria Territoriale Grande Ospedale Metropolitano Niguarda, Milano, Italy
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Kogias E, Schmeiser B, Doostkam S, Brandt A, Hammen T, Zentner J, Ramantani G. Multilobar Resections for 3T MRI-Negative Epilepsy: Worth the Trouble? World Neurosurg 2018; 123:e338-e347. [PMID: 30502474 DOI: 10.1016/j.wneu.2018.11.170] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 11/12/2018] [Accepted: 11/19/2018] [Indexed: 12/01/2022]
Abstract
OBJECTIVE Multilobar resection in magnetic resonance imaging (MRI)-negative drug-resistant epilepsy warrants attention because they account for up to one third of MRI-negative epilepsy surgery. Despite their high prevalence, data are sparse, and the risk/benefit ratio continues to be debated. The present study investigated the postoperative seizure outcomes in this especially challenging subgroup. METHODS We retrospectively analyzed the data of 4 consecutive patients with 3T MRI-negative findings and drug-resistant focal epilepsy who had undergone multilobar epilepsy surgery at our institution. RESULTS The mean age at first surgery was 28.5 years (range, 14-48); 1 patient required 2 consecutive reoperations. The final resection was in the frontotemporal and temporo-parieto-occipital regions in 2 patients each. Histopathological examination revealed mild malformations of cortical development in 2 patients and focal cortical dysplasia type Ia and type IIa in 1 patient each. At the last follow-up examination (median, 3.3 years; range, 1-11), 2 patients were completely seizure free (Engel class Ia), 1 patient had experienced some disabling seizures after surgery but had been free of disabling seizures for 2 years at the last follow-up examination (Engel class Ic), and 1 patient had experienced worthwhile improvement (Engel class IIb) and had been seizure free for 1 year at the last follow-up examination. No surgical complications developed. CONCLUSIONS Our results have demonstrated that multilobar epilepsy surgery is effective for lasting seizure control for selected 3T MRI-negative candidates, leading to favorable outcomes for all 4 of our patients. Comprehensive multimodal preoperative evaluation is a prerequisite for postoperative success. Reevaluation should be considered for patients with seizure recurrence, because reoperation could be especially beneficial for selected patients who have not responded to an initially limited resection.
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Affiliation(s)
- Evangelos Kogias
- Department of Neurosurgery, Medical Center - University of Freiburg, Freiburg, Germany
| | - Barbara Schmeiser
- Department of Neurosurgery, Medical Center - University of Freiburg, Freiburg, Germany
| | - Soroush Doostkam
- Institute of Neuropathology, Medical Center - University of Freiburg, Freiburg, Germany
| | - Armin Brandt
- Epilepsy Center, Department of Neurosurgery, Medical Center - University of Freiburg, Freiburg, Germany
| | - Thilo Hammen
- Epilepsy Center, Department of Neurosurgery, Medical Center - University of Freiburg, Freiburg, Germany
| | - Josef Zentner
- Department of Neurosurgery, Medical Center - University of Freiburg, Freiburg, Germany
| | - Georgia Ramantani
- Epilepsy Center, Department of Neurosurgery, Medical Center - University of Freiburg, Freiburg, Germany; Department of Neuropediatrics, University Children's Hospital Zurich, Zurich, Switzerland.
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Jayakar P, Jayakar A, Libenson M, Arzimanoglou A, Rydenhag B, Cross JH, Bhatia S, Tassi L, Lachhwani D, Gaillard WD. Epilepsy surgery near or in eloquent cortex in children-Practice patterns and recommendations for minimizing and reporting deficits. Epilepsia 2018; 59:1484-1491. [PMID: 30033517 DOI: 10.1111/epi.14510] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Accepted: 06/13/2018] [Indexed: 01/16/2023]
Abstract
OBJECTIVE We aimed to investigate the current practices guiding surgical resection strategies involving epileptogenic zones (EZs) near or in eloquent cortex (EC) at pediatric epilepsy surgery centers worldwide. METHODS A survey was conducted among 40 respondents from 33 pediatric epilepsy surgery centers worldwide on the weight assigned to diagnostic tests used to define the EZ and EC, how EC is viewed, and how surgeries are planned for foci near or in eloquent cortex. RESULTS A descriptive analysis was performed that revealed considerable variation in the use of diagnostic tests and resective strategies toward EZ and EC. SIGNIFICANCE The wide variation in strategies may contribute to undesirable outcomes characterized by poor seizure control with added deficits and underscores the need to establish best practices in pediatric epilepsy surgery. The survey data were used to formulate a set of recommendations to help minimize deficits and to report them consistently.
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Affiliation(s)
- Prasanna Jayakar
- Department of Neurology and Comprehensive Epilepsy Program, Brain Institute, Nicklaus Children's Hospital, Miami, Florida
| | - Anuj Jayakar
- Department of Neurology and Epilepsy, Nicklaus Children's Hospital, Miami, Florida
| | - Mark Libenson
- Department of Neurology, Children's Hospital Boston, Boston, Massachusetts
| | - Alexis Arzimanoglou
- Clinical Epileptology, Sleep Disorders and Functional Neurology in Children, University Hospitals of Lyon, Lyon, France
| | - Bertil Rydenhag
- Epilepsy Research Group, Institute of Neuroscience and Physiology, Goteborg, Sweden
| | - J Helen Cross
- Department of Clinical & Experimental Epilepsy, Great Ormond Street Hospital, University College London, London, UK
| | - Sanjiv Bhatia
- Department of Neurosurgery, Miami Children's Hospital, Miami, Florida
| | - Laura Tassi
- Department of Neuroscience, Claudio Munari Epilepsy Surgery Centre, Milano, Italy
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Iimura Y, Jones K, Hattori K, Okazawa Y, Noda A, Hoashi K, Nonoda Y, Asano E, Akiyama T, Go C, Ochi A, Snead OC, Donner EJ, Rutka JT, Drake JM, Otsubo H. Epileptogenic high-frequency oscillations skip the motor area in children with multilobar drug-resistant epilepsy. Clin Neurophysiol 2017; 128:1197-1205. [PMID: 28521267 DOI: 10.1016/j.clinph.2017.03.031] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 03/07/2017] [Accepted: 03/13/2017] [Indexed: 11/18/2022]
Abstract
OBJECTIVE Subtotal hemispherectomy involves the resection of multiple lobes in children with drug-resistant epilepsy, skipping the motor area (MA). We determined epileptogenicity using the occurrence rate (OR) of high-frequency oscillations (HFOs) and the modulation index (MI), demonstrating strength of coupling between HFO and slow wave. We hypothesized that epileptogenicity increased over the multiple lobes but skipped the MA. METHODS We analyzed 23 children (14 subtotal hemispherectomy; 9 multilobar resections). Scalp video-EEG and magnetoencephalography were performed before surgery. We analyzed the OR(HFO) and MI(5 phases=0.5-8 Hz) on electrodes of total area, resection areas, and MA. We compared the data between good [International League Against Epilepsy (ILAE) class I-II] and poor (III-VI) seizure outcome groups. RESULTS ILAE class Ia outcome was achieved in 18 children. Among the MI(5 phases) in the resection areas, MI(3-4 Hz) was the highest. The OR(HFO) and MI(3-4 Hz) in both total area and resection areas were significantly higher in the good seizure outcome group than in the poor outcome group. The OR(HFO) and MI(3-4 Hz) in resection areas were significantly higher than in the MA. CONCLUSIONS Our patients with multilobar drug-resistant epilepsy showed evidence of multifocal epileptogenicity that specifically skipped the MA. SIGNIFICANCE This is the first study demonstrating that the electrophysiological phenotype of multifocal epilepsy specifically skips the MA using OR(HFO) and MI(3-4 Hz).
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Affiliation(s)
- Yasushi Iimura
- Division of Neurology, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Kevin Jones
- Division of Neurology, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Kyoko Hattori
- Division of Neurology, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Yushi Okazawa
- Division of Neurology, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Atsuko Noda
- Division of Neurology, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Kana Hoashi
- Division of Neurology, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Yutaka Nonoda
- Pediatrics and Neurology, Children's Hospital of Michigan, Wayne State University, Detroit, MI, USA
| | - Eishi Asano
- Pediatrics and Neurology, Children's Hospital of Michigan, Wayne State University, Detroit, MI, USA
| | - Tomoyuki Akiyama
- Department of Child Neurology, Okayama University Hospital, Okayama, Japan
| | - Cristina Go
- Division of Neurology, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Ayako Ochi
- Division of Neurology, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - O Carter Snead
- Division of Neurology, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Elizabeth J Donner
- Division of Neurology, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - James T Rutka
- Division of Neurosurgery, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - James M Drake
- Division of Neurosurgery, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Hiroshi Otsubo
- Division of Neurology, The Hospital for Sick Children, Toronto, Ontario, Canada.
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