1
|
Lee YJ. Advanced neuroimaging techniques for evaluating pediatric epilepsy. Clin Exp Pediatr 2020; 63:88-95. [PMID: 32024331 PMCID: PMC7073377 DOI: 10.3345/kjp.2019.00871] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Accepted: 11/06/2019] [Indexed: 01/11/2023] Open
Abstract
Accurate localization of the seizure onset zone is important for better seizure outcomes and preventing deficits following epilepsy surgery. Recent advances in neuroimaging techniques have increased our understanding of the underlying etiology and improved our ability to noninvasively identify the seizure onset zone. Using epilepsy-specific magnetic resonance imaging (MRI) protocols, structural MRI allows better detection of the seizure onset zone, particularly when it is interpreted by experienced neuroradiologists. Ultra-high-field imaging and postprocessing analysis with automated machine learning algorithms can detect subtle structural abnormalities in MRI-negative patients. Tractography derived from diffusion tensor imaging can delineate white matter connections associated with epilepsy or eloquent function, thus, preventing deficits after epilepsy surgery. Arterial spin-labeling perfusion MRI, simultaneous electroencephalography (EEG)-functional MRI (fMRI), and magnetoencephalography (MEG) are noinvasive imaging modalities that can be used to localize the epileptogenic foci and assist in planning epilepsy surgery with positron emission tomography, ictal single-photon emission computed tomography, and intracranial EEG monitoring. MEG and fMRI can localize and lateralize the area of the cortex that is essential for language, motor, and memory function and identify its relationship with planned surgical resection sites to reduce the risk of neurological impairments. These advanced structural and functional imaging modalities can be combined with postprocessing methods to better understand the epileptic network and obtain valuable clinical information for predicting long-term outcomes in pediatric epilepsy.
Collapse
Affiliation(s)
- Yun Jeong Lee
- Department of Pediatrics, Kyungpook National University Hospital, School of Medicine, Kyungpook National University, Daegu, Korea
| |
Collapse
|
2
|
Juhász C, John F. Utility of MRI, PET, and ictal SPECT in presurgical evaluation of non-lesional pediatric epilepsy. Seizure 2019; 77:15-28. [PMID: 31122814 DOI: 10.1016/j.seizure.2019.05.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2018] [Revised: 02/12/2019] [Accepted: 05/10/2019] [Indexed: 12/12/2022] Open
Abstract
Children with epilepsy and normal structural MRI pose a particular challenge in localization of epileptic foci for surgical resection. Many of these patients have subtle structural lesions such as mild cortical dysplasia that can be missed by conventional MRI but may become detectable by optimized and advanced MRI acquisitions and post-processing. Specificity of objective analytic techniques such as voxel-based morphometry remains an issue. Combination of MRI with functional imaging approaches can improve the accuracy of detecting epileptogenic brain regions. Analysis of glucose positron emission tomography (PET) combined with high-resolution MRI can optimize detection of hypometabolic cortex associated with subtle cortical malformations and can also enhance presurgical evaluation in children with epileptic spasms. Additional PET tracers may detect subtle epileptogenic lesions and cortex with enhanced specificity in carefully selected subgroups with various etiologies; e.g., increased tryptophan uptake can identify epileptogenic cortical dysplasia in the interictal state. Subtraction ictal SPECT can be also useful to delineate ictal foci in those with non-localizing PET or after failed surgical resection. Presurgical delineation of language and motor cortex and the corresponding white matter tracts is increasingly reliable by functional MRI and DTI techniques; with careful preparation, these can be useful even in young and sedated children. While evidence-based pediatric guidelines are still lacking, the data accumulated in the last decade strongly indicate that multimodal imaging with combined analysis of MRI, PET, and/or ictal SPECT data can optimize the detection of subtle epileptogenic lesions and facilitate seizure-free outcome while minimizing the postsurgical functional deficit in children with normal conventional MRI.
Collapse
Affiliation(s)
- Csaba Juhász
- Department of Pediatrics, Wayne State University, PET Center and Translational Imaging Laboratory, Children's Hospital of Michigan, 3901 Beaubien St., Detroit, Michigan, 48201, USA; Departments of Neurology and Neurosurgery, Wayne State University, 4201 St. Antoine St., Detroit, Michigan, 48201, USA.
| | - Flóra John
- Department of Pediatrics, Wayne State University, PET Center and Translational Imaging Laboratory, Children's Hospital of Michigan, 3901 Beaubien St., Detroit, Michigan, 48201, USA; Department of Neurology, University of Pécs, H-7623, Rét u. 2., Pécs, Hungary.
| |
Collapse
|
3
|
Challenges in managing epilepsy associated with focal cortical dysplasia in children. Epilepsy Res 2018; 145:1-17. [DOI: 10.1016/j.eplepsyres.2018.05.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Revised: 04/30/2018] [Accepted: 05/12/2018] [Indexed: 12/15/2022]
|
4
|
Khan UG, Schmidt MH. A Survey of Magnetic Resonance Imaging Protocols for the Investigation of Epilepsy in Canadian Academic Referral Centres. Can Assoc Radiol J 2018; 69:277-281. [DOI: 10.1016/j.carj.2018.04.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2017] [Revised: 03/02/2018] [Accepted: 04/03/2018] [Indexed: 11/16/2022] Open
Affiliation(s)
- Usman G. Khan
- MD Program, Undergraduate Medical Education, Faculty of Medicine, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Matthias H. Schmidt
- Department of Diagnostic Radiology, Faculty of Medicine, Dalhousie University, Halifax, Nova Scotia, Canada
| |
Collapse
|
5
|
Delev D, Quesada CM, Grote A, Boström JP, Elger C, Vatter H, Surges R. A multimodal concept for invasive diagnostics and surgery based on neuronavigated voxel-based morphometric MRI postprocessing data in previously nonlesional epilepsy. J Neurosurg 2018. [DOI: 10.3171/2016.12.jns161676] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVEDiagnosis and surgical treatment of refractory and apparent nonlesional focal epilepsy is challenging. Morphometric MRI voxel-based and other postprocessing methods can help to localize the epileptogenic zone and thereby support the planning of further invasive electroencephalography (EEG) diagnostics, and maybe resective epilepsy surgery.METHODSThe authors developed an algorithm to implement regions of interest (ROI), based on postprocessed MRI data, into a neuronavigation tool. This was followed by stereotactic ROI-guided implantation of depth electrodes and ROI-navigated resective surgery. Data on diagnostic yield, histology, and seizure outcome were collected and evaluated.RESULTSFourteen consecutive patients with apparently nonlesional epilepsy were included in this study. Reevaluation of the MR images with the help of MRI postprocessing analysis led to the identification of probable subtle lesions in 11 patients. Additional information obtained by SPECT imaging and MRI reevaluation suggested possible lesions in the remaining 3 patients. The ROI-guided invasive implantation of EEG yielded interictal and ictal activity in 13 patients who were consequently referred to resective surgery. Despite the apparently negative MRI findings, focal cortical dysplasia was found in 64% of the patients (n = 9). At the last available outcome, 8 patients (57%) were completely seizure free (International League Against Epilepsy Class 1).CONCLUSIONSThe results demonstrate the feasibility and usefulness of a robust and straightforward algorithm for implementation of MRI postprocessing-based targets into the neuronavigation system. This approach allowed the stereotactic implantation of a low number of depth electrodes only, which confirmed the seizure-onset hypothesis in 90% of the cases without causing any complications. Furthermore, the neuronavigated ROI-guided lesionectomy helped to perform resective surgery in this rather challenging subgroup of patients with apparent nonlesional epilepsy.
Collapse
Affiliation(s)
| | - Carlos M. Quesada
- 2Epileptology, University of Bonn, University Medical Center, Bonn, Germany
| | | | | | - Christian Elger
- 2Epileptology, University of Bonn, University Medical Center, Bonn, Germany
| | | | - Rainer Surges
- 2Epileptology, University of Bonn, University Medical Center, Bonn, Germany
| |
Collapse
|
6
|
|
7
|
Calik M, Sen Dokumaci D, Sarikaya S, Demir M, Isik I, Kazanasmaz H, Kaya C, Kandemir H. Brain metabolite values in children with breath-holding spells. Neuropsychiatr Dis Treat 2017; 13:1655-1660. [PMID: 28721046 PMCID: PMC5499924 DOI: 10.2147/ndt.s135842] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Breath-holding spells are benign, paroxysmal events with apnea and postural tone changes after a crying episode in infants. The objective of this study was to investigate the pathologies in brain metabolite values in the absence of seizure in children with breath-holding spells by using magnetic resonance spectroscopy (MRS). Brain MRS examination was performed on 18 children with breath-holding spells and 13 neurologically normal children who were included as the control group. There was no significant difference in terms of N-acetyl aspartate (NAA), choline (Cho), creatine (Cr), and myoinositol (mI) levels and also in terms of NAA/Cr, Cho/Cr, and mI/Cr ratios between the patients and the control group (all P>0.05). Our study suggested that there is no permanent neuronal damage in patients with breath-holding spells. This result confirms the previous studies, which reported no permanent neuronal damage in patients with breath-holding spells.
Collapse
Affiliation(s)
| | | | | | - Mahmut Demir
- Department of Pediatrics, Harran University School of Medicine
| | - Ilhan Isik
- Department of Pediatric Neurology, Eyyubiye Training and Research Hospital
| | | | - Cemil Kaya
- Department of Pediatrics, Harran University School of Medicine
| | - Hasan Kandemir
- Department of Child and Adolescent Psychiatry, Harran University School of Medicine, Sanliurfa, Turkey
| |
Collapse
|
8
|
Martinez-Rios C, McAndrews MP, Logan W, Krings T, Lee D, Widjaja E. MRI in the evaluation of localization-related epilepsy. J Magn Reson Imaging 2016; 44:12-22. [PMID: 27115073 DOI: 10.1002/jmri.25269] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Accepted: 03/28/2016] [Indexed: 11/06/2022] Open
Abstract
This article covers the MRI evaluation of patients with epilepsy, with a focus on neuroimaging in those with localization-related epilepsy who may be potential epilepsy surgery candidates. The article includes structural MRI to identify a lesion, functional MRI to identify the eloquent cortex and diffusion tensor imaging to identify the eloquent white matter tracts. We consider the equipment, protocol or procedures, and reporting of MRI in patients with epilepsy. Recommendations for both adult and pediatric patients are described for protocols and procedures. The authors hope that this article will provide a standardized approach for clinical imaging of patients with suspected localization-related epilepsy who may be evaluated for epilepsy surgery. J. Magn. Reson. Imaging 2016.
Collapse
Affiliation(s)
| | | | - William Logan
- Division of Neurology, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Timo Krings
- University Health Network, Toronto, Ontario, Canada
| | - Donald Lee
- London Health Sciences Center, London, Ontario, Canada
| | - Elysa Widjaja
- Department of Radiology, Hospital for Sick Children, Toronto, Ontario, Canada
| |
Collapse
|
9
|
Soares BP, Porter SG, Saindane AM, Dehkharghani S, Desai NK. Utility of double inversion recovery MRI in paediatric epilepsy. Br J Radiol 2015; 89:20150325. [PMID: 26529229 DOI: 10.1259/bjr.20150325] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Detecting focal abnormalities in MRI examinations of children with epilepsy can be a challenging task given the frequently subtle appearance of cortical dysplasia, mesial temporal sclerosis and similar lesions. In this report, we demonstrate the utility of double inversion recovery MRI in the detection of paediatric epileptogenic abnormalities, promoted primarily by increased lesion conspicuity due to complementary suppression of both cerebrospinal fluid and normal white matter signal.
Collapse
Affiliation(s)
- Bruno P Soares
- 1 Department of Radiology and Imaging Sciences, Neuroradiology Division, Emory University, Atlanta, GA, USA.,2 Children's Healthcare of Atlanta at Egleston, Atlanta, GA, USA
| | - Samuel G Porter
- 1 Department of Radiology and Imaging Sciences, Neuroradiology Division, Emory University, Atlanta, GA, USA
| | - Amit M Saindane
- 1 Department of Radiology and Imaging Sciences, Neuroradiology Division, Emory University, Atlanta, GA, USA
| | - Seena Dehkharghani
- 1 Department of Radiology and Imaging Sciences, Neuroradiology Division, Emory University, Atlanta, GA, USA
| | - Nilesh K Desai
- 1 Department of Radiology and Imaging Sciences, Neuroradiology Division, Emory University, Atlanta, GA, USA.,2 Children's Healthcare of Atlanta at Egleston, Atlanta, GA, USA
| |
Collapse
|
10
|
Abud LG, Thivard L, Abud TG, Nakiri GS, dos Santos AC, Dormont D. Partial epilepsy: A pictorial review of 3 TESLA magnetic resonance imaging features. Clinics (Sao Paulo) 2015; 70:654-61. [PMID: 26375569 PMCID: PMC4557590 DOI: 10.6061/clinics/2015(09)10] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Epilepsy is a disease with serious consequences for patients and society. In many cases seizures are sufficiently disabling to justify surgical evaluation. In this context, Magnetic Resonance Imaging (MRI) is one of the most valuable tools for the preoperative localization of epileptogenic foci. Because these lesions show a large variety of presentations (including subtle imaging characteristics), their analysis requires careful and systematic interpretation of MRI data. Several studies have shown that 3 Tesla (T) MRI provides a better image quality than 1.5 T MRI regarding the detection and characterization of structural lesions, indicating that high-field-strength imaging should be considered for patients with intractable epilepsy who might benefit from surgery. Likewise, advanced MRI postprocessing and quantitative analysis techniques such as thickness and volume measurements of cortical gray matter have emerged and in the near future, these techniques will routinely enable more precise evaluations of such patients. Finally, the familiarity with radiologic findings of the potential epileptogenic substrates in association with combined use of higher field strengths (3 T, 7 T, and greater) and new quantitative analytical post-processing techniques will lead to improvements regarding the clinical imaging of these patients. We present a pictorial review of the major pathologies related to partial epilepsy, highlighting the key findings of 3 T MRI.
Collapse
Affiliation(s)
- Lucas Giansante Abud
- Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo, Neuroradiology, Ribeirão Preto/, SP,, Brazil
- Corresponding author: E-mail:
| | - Lionel Thivard
- Hôpital de laPitié-Salpêtri`re, Neurology/Neuroradiology, Paris, France
| | | | - Guilherme Seizem Nakiri
- Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo, Neuroradiology, Ribeirão Preto/, SP,, Brazil
| | - Antonio Carlos dos Santos
- Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo, Neuroradiology, Ribeirão Preto/, SP,, Brazil
| | - Didier Dormont
- Hôpital de laPitié-Salpêtri`re, Neurology/Neuroradiology, Paris, France
| |
Collapse
|
11
|
3T-MRI in patients with pharmacoresistant epilepsy and a vagus nerve stimulator: A pilot study. Epilepsy Res 2015; 110:62-70. [DOI: 10.1016/j.eplepsyres.2014.11.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 10/25/2014] [Accepted: 11/11/2014] [Indexed: 12/30/2022]
|
12
|
Toledo M, Sarria-Estrada S, Quintana M, Auger C, Salas-Puig X, Santamarina E, Vert C, Rovira A. 3 TESLA MR imaging in adults with focal onset epilepsy. Clin Neurol Neurosurg 2013; 115:2111-6. [PMID: 23969199 DOI: 10.1016/j.clineuro.2013.07.039] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 07/01/2013] [Accepted: 07/27/2013] [Indexed: 12/01/2022]
Abstract
OBJECTIVE The finding of cerebral epileptogenic lesions in magnetic resonance (MR) has demonstrated to be a relevant prognostic factor for potential surgical candidates. In a series of consecutive adults with focal onset epilepsy, we investigated the yield of 3T MR imaging for detecting epileptogenic cerebral lesions. MATERIALS AND METHODS We prospectively recruited 161 adult patients with a diagnosis of focal epilepsy, all of whom underwent standardized MR imaging study performed with a 3T magnet. RESULTS Lesion-related epilepsy was observed in 48% of patients, and 12% of cryptogenic patients showed subtle or non-specific lesions related to the epileptogenic source. The most common findings were focal cortical dysplasia and vascular lesions, followed by mesial temporal sclerosis, tumors, and scars from previous cerebral injuries. Patients older than 72 years were more likely to have vascular epilepsy. CONCLUSIONS Diagnostic assessment using a standardized 3T MR imaging protocol for focal-onset epilepsy detects lesions in nearly half the patients. Our results indicate that elders with focal epilepsy should be searched for vascular lesions.
Collapse
Affiliation(s)
- Manuel Toledo
- Epilepsy Unit, Neurology Department, Hospital Universitari Vall d'Hebron, Universitat Autonoma de Barcelona, Passeig Vall d'Hebron 119-129, 08035 Barcelona, Spain.
| | | | | | | | | | | | | | | |
Collapse
|
13
|
Kadom N, Trofimova A, Vezina GL. Utility of magnetization transfer T1 imaging in children with seizures. AJNR Am J Neuroradiol 2012; 34:895-8. [PMID: 23153867 DOI: 10.3174/ajnr.a3396] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Failure to detect FCD and similar lesions encountered in patients with tuberous sclerosis can have significant clinical consequences, such as preventing surgical intervention for medically refractory epilepsy and misguiding prognostic information regarding cognitive development. Here, we show the beneficial effects on detection of FCD and cortical tubers when using a magnetization transfer T1 sequence for children with seizures who underwent MR imaging at our institution.
Collapse
Affiliation(s)
- N Kadom
- Children's National Medical Center, Washington, DC 20010, USA.
| | | | | |
Collapse
|
14
|
Abstract
Our understanding of epileptogenesis is still limited. Knowledge is increasing with regard to structural and functional changes in chronic stages of epilepsy. At the same time, we have to appreciate that there is a significant lack of such information in new-onset epilepsy. The First Halifax International Epilepsy Conference tried to fill this gap, focusing on the contribution of advanced neuroimaging in early stages of epilepsy. The following article aims to synthesize the themes that emerged from this meeting. Participants agreed that (1) there is a need for a unified theory of epileptogenesis, addressing the interplay of functional and structural brain changes; (2) neuroimaging reveals widespread brain alterations in epilepsy; (3) advances in neuroimaging challenge the concept of "MRI-negative" (magnetic resonance imaging negative) focal epilepsy; (4) methodologic limitations and potential confounders must be considered in the translation of innovative imaging approaches to clinical practice; and (5) there is an urgent need for longitudinal studies that begin early in the disease process.
Collapse
Affiliation(s)
- Matthias H Schmidt
- Department of Radiology Medicine, Neurology, Dalhousie University, Halifax, Nova Scotia, Canada.
| | | |
Collapse
|