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Wan HJ, Hu WH, Wang X, Zhang C, Wang SS, Zheng Z, Zhou F, Sang L, Zhang K, Zhang JG, Shao XQ. Interictal pattern on scalp electroencephalogram predicts excellent surgical outcome of epilepsy caused by focal cortical dysplasia. Epilepsia Open 2022; 7:350-360. [PMID: 35202517 PMCID: PMC9159252 DOI: 10.1002/epi4.12587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 12/25/2021] [Accepted: 02/18/2022] [Indexed: 11/06/2022] Open
Abstract
OBJECTIVE Focal cortical dysplasia (FCD) represents an essential cause of drug-resistant epilepsy with surgery as an effective treatment option. This study aimed to identify the important predictors of favorable surgical outcomes and the impact of the interictal scalp electroencephalogram (EEG) patterns in predicting postsurgical seizure outcomes. METHODS We retrospectively evaluated 210 consecutive patients between 2015 and 2019. They were diagnosed with FCD by pathology, underwent resection, and had at least one year of postsurgical follow-up. Predictors of seizure freedom were analyzed. RESULTS Based on the information at the latest follow-up, seizure outcome was classified as Engel Class I (seizure-free) in 81.4% and Engel Class II-IV (non-seizure-free) in 18.6% of patients. There were 43, 105, and 62 cases of FCD type I, type II, and type III, respectively. The interictal EEG showed a repetitive discharge pattern (REDP) in 87 (41.4%) patients, polyspike discharge pattern (PDP) in 41 (19.5%), and the coexistence of REDP and PDP in the same location in 32 (15.2%) patients. The analyzed patterns in order of frequency were repetitive discharges lasting 5 seconds or more (32.4%); polyspikes (16.7%); RED type 1 (11.4%); continuous epileptiform discharges occupying >80% of the recording (11.4%); RED type 2 (6.2%); brushes (3.3%); focal, fast, continuous spikes (2.4%); focal fast rhythmic epileptiform discharges (1.43%); and frequent rhythmic bursting epileptiform activity (1.4%). The coexistence of REDP and PDP in the same location on scalp EEG and complete resection of the assumed epileptogenic zone (EZ) was independently associated with favorable postsurgical prognosis. SIGNIFICANCE Resective epilepsy surgery for intractable epilepsy caused by FCD has favorable outcomes. Interictal scalp EEG patterns were revealed to be predictive of excellent surgical outcomes and may help clinical decision-making and enable better presurgical evaluation.
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Affiliation(s)
- Hui-Juan Wan
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.,China National Clinical Research Center for Neurological Diseases (NCRC-ND), Beijing, China.,Department of Neurology, First Affiliated Hospital, Xiamen University, Xiamen, China
| | - Wen-Han Hu
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.,Stereotactic and Functional Neurosurgery Laboratory, Beijing Neurosurgical Institute, Capital Medical University, Beijing, China
| | - Xiu Wang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.,Beijing Key Laboratory of Neurostimulation, Beijing, China
| | - Chao Zhang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.,Beijing Key Laboratory of Neurostimulation, Beijing, China
| | - Sheng-Song Wang
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.,China National Clinical Research Center for Neurological Diseases (NCRC-ND), Beijing, China
| | - Zhong Zheng
- Department of Neurosurgery, Beijing Fengtai Hospital, Beijing, China
| | - Feng Zhou
- Department of Neurosurgery, Beijing Fengtai Hospital, Beijing, China
| | - Lin Sang
- Department of Neurosurgery, Beijing Fengtai Hospital, Beijing, China
| | - Kai Zhang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.,Beijing Key Laboratory of Neurostimulation, Beijing, China
| | - Jian-Guo Zhang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.,Stereotactic and Functional Neurosurgery Laboratory, Beijing Neurosurgical Institute, Capital Medical University, Beijing, China.,Beijing Key Laboratory of Neurostimulation, Beijing, China
| | - Xiao-Qiu Shao
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.,China National Clinical Research Center for Neurological Diseases (NCRC-ND), Beijing, China
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Repetitive miniature spikes - An underreported EEG pattern. Clin Neurophysiol 2019; 131:40-45. [PMID: 31751838 DOI: 10.1016/j.clinph.2019.08.028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 08/22/2019] [Accepted: 08/24/2019] [Indexed: 11/23/2022]
Abstract
OBJECTIVES Low-voltage repetitive spikes are mainly described with invasive recordings and considered highly suggestive for focal cortical dysplasia (FCD). This EEG pattern has received less attention in routine scalp EEG. METHODS Prospective collection of EEGs with low-voltage (<50 µV) repetitive spikes (repetitive miniature spikes - RMS) between July 1982 and July 2017 at the EEG laboratory of the Medical University of Innsbruck. We analyzed patterns of RMS on routine scalp EEG recordings and examined the relationship to clinical and brain imaging data. RESULTS Overall, RMS were seen in 38 patients representing zero to four observations out of 5000 records per year. RMS occurred rhythmically in 14, periodically in 17 and irregularly in seven patients. The EEG pattern appeared with a frontal and central predominance. All but five patients had epilepsies; eleven patients had non-convulsive status epilepticus. Cerebral magnetic resonance imaging (cMRI) detected malformations of cortical development in eleven patients, including six patients with focal cortical dysplasias. CONCLUSIONS RMS are rare EEG patterns indicating focal epilepsy. Their observation on routine scalp EEGs should prompt further clinic-radiologic investigation. SIGNIFICANCE RMS resemble a clearly recognizable pattern in routine EEG, which is highly associated with focal epilepsy. The term is descriptive and can be added to the red flags, which can be found on routine EEG indicating underlying structural brain pathology, often in form of focal cortical dysplasia.
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Epitashvili N, San Antonio-Arce V, Brandt A, Schulze-Bonhage A. Scalp electroencephalographic biomarkers in epilepsy patients with focal cortical dysplasia. Ann Neurol 2018; 84:564-575. [DOI: 10.1002/ana.25322] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 08/24/2018] [Accepted: 08/27/2018] [Indexed: 12/18/2022]
Affiliation(s)
- Nino Epitashvili
- Epilepsy Center; University Medical Center; Freiburg Germany
- MediClub Georgia; Tbilisi Georgia
| | - Victoria San Antonio-Arce
- Epilepsy Center; University Medical Center; Freiburg Germany
- Hospital Sant Joan de Déu; Barcelona Spain
| | - Armin Brandt
- Epilepsy Center; University Medical Center; Freiburg Germany
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Cossu M, Pelliccia V, Gozzo F, Casaceli G, Francione S, Nobili L, Mai R, Castana L, Sartori I, Cardinale F, Lo Russo G, Tassi L. Surgical treatment of polymicrogyria-related epilepsy. Epilepsia 2016; 57:2001-2010. [PMID: 27778326 DOI: 10.1111/epi.13589] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/26/2016] [Indexed: 02/02/2023]
Abstract
OBJECTIVE The role of resective surgery in the treatment of polymicrogyria (PMG)-related focal epilepsy is uncertain. Our aim was to retrospectively evaluate the seizure outcome in a consecutive series of patients with PMG-related epilepsy who received, or did not receive, surgical treatment, and to outline the clinical characteristics of patients who underwent surgery. METHODS We evaluated 64 patients with epilepsy associated with magnetic resonance imaging (MRI)-documented PMG. After presurgical evaluation, 32 patients were excluded from surgical treatment and 32 were offered surgery, which was declined by 8 patients. Seizure outcome was assessed in the 40 nonsurgical and 24 surgical patients. RESULTS Of 40 nonsurgical patients, 8 (20%) were seizure-free after a mean follow-up of 91.7 ± (standard deviation) 59.5 months. None of the eight patients who declined surgical treatment was seizure-free (mean follow-up: 74.3 ± 60.6 months). These seizure outcomes differ significantly (p = 0.000005 and p = 0.0003, respectively) from that of the 24 surgical patients, 18 of whom (66.7%) were Engel's class I postoperatively (mean follow-up: 66.5 ± 54.0 months). Of the eight patients excluded from surgery for seizure control at first visit, two had seizure recurrence at last contact. At last contact, antiepileptic drugs (AEDs) had been withdrawn in 6 of 24 surgical and in one of 40 nonsurgical cases (p = 0.0092). SIGNIFICANCE The present study indicates that, at least in a subset of adequately selected patients with PMG-related epilepsy, surgery may provide excellent seizure outcomes. Furthermore, it suggests that surgery is superior to AEDs for achieving seizure freedom in these cases.
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Affiliation(s)
- Massimo Cossu
- Department of Neuroscience, Center for Epilepsy Surgery, Niguarda Hospital, Milan, Italy
| | - Veronica Pelliccia
- Department of Neuroscience, Center for Epilepsy Surgery, Niguarda Hospital, Milan, Italy
| | - Francesca Gozzo
- Department of Neuroscience, Center for Epilepsy Surgery, Niguarda Hospital, Milan, Italy
| | - Giuseppe Casaceli
- Department of Neuroscience, Center for Epilepsy Surgery, Niguarda Hospital, Milan, Italy
| | - Stefano Francione
- Department of Neuroscience, Center for Epilepsy Surgery, Niguarda Hospital, Milan, Italy
| | - Lino Nobili
- Department of Neuroscience, Center for Epilepsy Surgery, Niguarda Hospital, Milan, Italy
| | - Roberto Mai
- Department of Neuroscience, Center for Epilepsy Surgery, Niguarda Hospital, Milan, Italy
| | - Laura Castana
- Department of Neuroscience, Center for Epilepsy Surgery, Niguarda Hospital, Milan, Italy
| | - Ivana Sartori
- Department of Neuroscience, Center for Epilepsy Surgery, Niguarda Hospital, Milan, Italy
| | - Francesco Cardinale
- Department of Neuroscience, Center for Epilepsy Surgery, Niguarda Hospital, Milan, Italy
| | - Giorgio Lo Russo
- Department of Neuroscience, Center for Epilepsy Surgery, Niguarda Hospital, Milan, Italy
| | - Laura Tassi
- Department of Neuroscience, Center for Epilepsy Surgery, Niguarda Hospital, Milan, Italy
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Shain C, Ramgopal S, Fallil Z, Parulkar I, Alongi R, Knowlton R, Poduri A. Polymicrogyria-associated epilepsy: a multicenter phenotypic study from the Epilepsy Phenome/Genome Project. Epilepsia 2013; 54:1368-75. [PMID: 23750890 DOI: 10.1111/epi.12238] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/29/2013] [Indexed: 01/14/2023]
Abstract
PURPOSE Polymicrogyria (PMG) is an epileptogenic malformation of cortical development. We describe the clinical epilepsy and imaging features of a large cohort with PMG-related epilepsy. METHODS Participants were recruited through the Epilepsy Phenome/Genome Project, a multicenter collaborative effort to collect detailed phenotypic data on individuals with epilepsy. We reviewed phenotypic data from participants with epilepsy and PMG. KEY FINDINGS We identified 87 participants, 43 female and 44 male, with PMG and epilepsy. Median age of seizure onset was 3 years (range <1 month to 37 years). Most presented with focal epilepsy (87.4%), some in combination with seizures generalized from onset (23.0%). Focal seizures with dyscognitive features were most common (54.3%). Of those presenting with generalized seizure types, infantile spasms were most prevalent (45.2%). The most common topographic pattern was perisylvian PMG (77.0%), of which the majority was bilateral (56.7%). Generalized PMG presented with an earlier age of seizure onset (median age of 8 months) and an increased prevalence of developmental delay prior to seizure onset (57.1%). Of the unilateral, and asymmetric bilateral groups where PMG was more involved in one hemisphere, the majority (71.4%) of participants had seizures that lateralized to the same hemisphere as the PMG or the hemisphere with greater involvement. SIGNIFICANCE Participants with PMG had both focal and generalized onset of seizures. Our data confirm the involvement of known topographic patterns of PMG and suggest that more extensive distributions of PMG present with an earlier age of seizure onset and increased prevalence of developmental delay prior to seizure onset.
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Affiliation(s)
- Catherine Shain
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA
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Abstract
Whereas there is no specific neurosurgical technique in pediatric epilepsy, the frequency of each type of surgery is very different from epilepsy surgery applied in adults, and reflects the underlying etiologies, which are much more diverse in children, with malformations of cortical development and tumors as the prevailing etiologies. Extensive resective or disconnective procedures for extratemporal epilepsy are more frequently performed in infants and younger children, whereas temporo-mesial resection is by far the most common surgical treatment for adults with epilepsy. More recently, less invasive techniques in children with an extensive epileptogenic zone, such as multilobar disconnection, hemispherotomy and other functional hemispherectomy variants, have been introduced in order to reduce duration of surgery, perioperative morbidity and length of hospital stay. Likewise, minimally invasive techniques are utilized, such as the endoscopic disconnection of hypothalamic hamartomas for gelastic epilepsy. This development has been encouraged with the introduction of image-guided navigation systems for the preoperative planning and during surgery. Historically, epilepsy surgery for children has been established much later than for adults. Apart from the particular aspects in perioperative management of younger infants, surgery-related morbidity as well as seizure outcome is in general similar to those in adults, depending rather on each type of surgery.
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Affiliation(s)
- Georg Dorfmüller
- Division of Pediatric Neurosurgery, Fondation Ophtalmologique Adolphe de Rothschild, Paris, France; INSERM, U663, Paris, France.
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Noachtar S, Bilgin O, Rémi J, Chang N, Midi I, Vollmar C, Feddersen B. Interictal regional polyspikes in noninvasive EEG suggest cortical dysplasia as etiology of focal epilepsies. Epilepsia 2008; 49:1011-7. [PMID: 18363706 DOI: 10.1111/j.1528-1167.2008.01583.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
PURPOSE To evaluate the clinical significance of interictal regional polyspikes in focal epilepsies secondary to cortical dysplasia. METHODS We performed a data search for the term "regional polyspikes" in the database of our epilepsy-monitoring unit. Patients with generalized epilepsies including Lennox-Gastaut syndrome were excluded. Regional interictal epileptiform discharges were recorded in 513 patients with noninvasive EEG. RESULTS We identified 29 patients with interictal regional polyspikes and focal epilepsies. Another 484 patients showed regional epileptiform discharges other than polyspikes. The etiology of the epilepsy was significantly more frequently cortical dysplasia in the group of patients with regional polyspikes (35%, 10 of 29 patients) than in the patients with other regional epileptiform discharges (5%, 24 of 484 patients) (p < 0.01). The polyspikes were significantly more frequently localized to the extratemporal (72%; n = 21) than temporal (28%; n = 8) regions (p < 0.01). In contrast, regional epileptiform discharges other than polyspikes were significantly more frequently localized to the temporal lobe (75%; n = 362) than extratemporal regions (25%; n = 122) (p < 0.01). Eight of the 10 patients with focal cortical dysplasia had extratemporal polyspikes. DISCUSSION Noninvasively recorded regional polyspikes suggest cortical dysplasias as etiology of predominantly extratemporal epilepsies.
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Affiliation(s)
- Soheyl Noachtar
- Department of Neurology, Epilepsy Center, University of Munich, Munich, Germany.
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Işik U, Dinçer A, Ozek MM. Surgical treatment of polymicrogyria with advanced radiologic and neurophysiologic techniques. Childs Nerv Syst 2007; 23:443-8. [PMID: 17171381 DOI: 10.1007/s00381-006-0262-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2006] [Revised: 09/13/2006] [Indexed: 10/23/2022]
Abstract
INTRODUCTION Coexistence of multiple seizure types, inclusion of the motor cortex in the epileptogenic zone, and poor delimitation of the abnormal cortex make most patients with polymicrogyria (PMG) unlikely candidates for epilepsy surgery (Guerrini R et al., Epilepsy and malformations of the cerebral cortex in Epileptic syndromes in infancy, childhood and adolescence, 2005). CASE REPORT We present here a child with frontal PMG and intractable epilepsy evaluated with advanced magnetic resonance imaging (MRI) and neurophysiologic techniques. Diffusion tensor imaging and fiber tractography showed severe involvement of neighboring white matter tracts besides the cortex. The evaluation also included functional MRI, chronic subdural electroencephalogram monitoring, and intra-operative motor mapping. The patient had a decrease in seizure frequency and an increase in his developmental skills after the surgery. CONCLUSION Advanced neuroradiologic and neurophysiologic techniques are required to provide an effective and safe resection of the epileptogenic cortex in cortical dysplasias.
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Affiliation(s)
- Uğur Işik
- Division of Pediatric Neurology, Acibadem Institute of Neurological Sciences, Istanbul, Turkey.
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Tinkle BT, Schorry EK, Franz DN, Crone KR, Saal HM. Epidemiology of hemimegalencephaly: a case series and review. Am J Med Genet A 2006; 139:204-11. [PMID: 16283674 DOI: 10.1002/ajmg.a.31024] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Hemimegalencephaly (HME) is a congenital brain malformation characterized by unilateral enlargement of the cerebral hemisphere. Clinically, HME is typically associated with hemiparesis, psychomotor retardation, and intractable seizures usually apparent soon after birth. HME is often an isolated finding, but it has been described as an occasional feature of a large number of syndromes, many of which may not be readily identified at birth. There are a multitude of case series and reports of HME in the English literature; however, there is no comprehensive, unbiased, detailed survey characterizing the proportion of cases of HME that are associated with a syndrome. We performed a retrospective study of all cases of HME seen at our institution from 1990 to 2003. Of the 15 cases of HME identified, 53% (8/15) were non-syndromic and 47% (7/15) of the cases were associated with a known or suspected genetic syndrome. In patients with syndromic HME, many of the syndromic features were not readily discernible at birth or in early infancy. It is, therefore, imperative to continually evaluate any infant with HME for signs and symptoms of these and other syndromes. Knowing the relative differential diagnosis will lead to a more comprehensive evaluation, improvement in expectant management, and appropriate counseling of families before considering radical surgical options such as hemispherectomy.
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Affiliation(s)
- Brad T Tinkle
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA.
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Ishibashi H, Simos PG, Wheless JW, Baumgartner JE, Kim HL, Castillo EM, Davis RN, Papanicolaou AC. Localization of ictal and interictal bursting epileptogenic activity in focal cortical dysplasia: agreement of magnetoencephalography and electrocorticography. Neurol Res 2002; 24:525-30. [PMID: 12238616 DOI: 10.1179/016164102101200483] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Focal cortical dysplasia (FCD) is often associated with severe partial epilepsy. In such cases, interictal frequent rhythmic bursting epileptiform activity (FBREA) on both scalp electroencephalography (EEG) and electrocorticography (ECoG) is generally accepted to be identical to the ictal epileptiform activity. We used magnetoencephalography (or Magnetic Source Imaging (MSI)) to determine the epileptogenic zone in a 6-year-old patient with histopathologically proven FCD and normal magnetic resonance imaging (MRI). MSI was used to localize the sources of both ictal activity and FRBEA, which was then compared with ECoG findings. The intracranial sources of both types of activity co-localized in the left inferior frontal and superior temporal gyri. The location and extent of the epileptogenic area determined by MSI was essentially identical to that determined directly through extra-operative ECoG. In the absence of structural abnormalities detectable on MRI, the noninvasive method of MSI provided valuable information regarding the location and extent of the primary epileptogenic area. This was critical for pre-surgical planning regarding placement of intracranial electrodes and for risk-benefit evaluation.
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Affiliation(s)
- Hideaki Ishibashi
- Department of Neurosurgery, Vivian L Smith Center for Neurologic Research, The University of Texas Health Science Center at Houston, 77030, USA.
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Kuruvilla A, Flink R. Focal fast rhythmic epileptiform discharges on scalp EEG in a patient with cortical dysplasia. Seizure 2002; 11:330-4. [PMID: 12076106 DOI: 10.1053/seiz.2001.0610] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
A distinctive scalp electroencephalographic (EEG) pattern of focal fast rhythmic epileptiform discharges (FREDs) in a 23-year-old man with symptomatic localization related epilepsy is presented. Magnetic resonance imaging (MRI) of the brain revealed cortical dysplasia over the right temporal region where the peculiar EEG abnormality was detected. We suggest that this characteristic EEG pattern may be predictive of focal cortical dysplasia (FCD). A brief review of the rhythmic EEG abnormalities in FCDs is also presented.
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Affiliation(s)
- Abraham Kuruvilla
- Department of Clinical Neurophysiology, Centre for Neuroscience, Uppsala University Hospital, Uppsala, Sweden.
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Abstract
Malformations of cortical development (MCD) are responsible for many cases of refractory epilepsy in adults and children. The results of surgical treatment are difficult to assess from the published literature. Judging from the limited number of adequately reported cases, approximately 40% of all cases of MCD treated surgically may be rendered seizure-free over a minimum 2-year follow-up period. This figure is the same for focal cortical dysplasia (FCD), the most common variety of MCD in surgical reports. In comparison with outcome for epilepsy associated with hippocampal sclerosis, this figure is low. Part of the difference may be artificial and related to limited reporting. Much of the difference is likely to relate to the complex underlying biology of MCD. Analysis of epileptogenesis in MCD has been undertaken. Different types of MCD have different sequelae. Some varieties are intrinsically epileptogenic; these include FCD and heterotopia. Although in most cases, the visualized MCD lies within the region of brain responsible for generating seizures (the epileptogenic zone), it may not constitute the entire epileptogenic zone in all cases. For polymicrogyria and schizencephaly in particular, the visualized abnormalities are probably not the most important component of the epileptogenic zone. There is evidence that the epileptogenic zone is spatially distributed and also, in some cases, temporally distributed. These findings may explain poor surgical outcome and the inadequacy of current presurgical evaluative methods. New preoperative techniques offer the opportunity of improved presurgical planning and selection of cases more likely to be rendered seizure-free by current surgical techniques. Of paramount importance is improved reporting. The establishment of a central registry may facilitate this aim. Specific recommendations are made for surgical strategies based on current experience and understanding.
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Affiliation(s)
- S M Sisodiya
- Epilepsy Research Group, Institute of Neurology, University College London, UK.
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Abstract
It is only a decade since the realization (facilitated by magnetic resonance imaging) in early 1990s that disorders of cortical development occupy an important place in the aetiologic categorization of epilepsy. Since then research has demonstrated the intrinsic epileptogenicity of disorders of cortical development, their genetic bases and their functional properties. Some of the key points of this most exciting medical and scientific enterprise are reviewed here, with an emphasis in the advances seen within the past 2 years.
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Affiliation(s)
- A Palmini
- Porto Alegre Epilepsy Surgery Program, Hospital São Lucas da Pontificia Universidade Católica do Rio Grande do Sul, Brazil
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