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Shih YC, Lee TH, Yu HY, Chou CC, Lee CC, Lin PT, Peng SJ. Machine Learning Quantitative Analysis of FDG PET Images of Medial Temporal Lobe Epilepsy Patients. Clin Nucl Med 2022; 47:287-293. [PMID: 35085166 PMCID: PMC8884180 DOI: 10.1097/rlu.0000000000004072] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 11/20/2021] [Indexed: 11/26/2022]
Abstract
PURPOSE 18F-FDG PET is widely used in epilepsy surgery. We established a robust quantitative algorithm for the lateralization of epileptogenic foci and examined the value of machine learning of 18F-FDG PET data in medial temporal lobe epilepsy (MTLE) patients. PATIENTS AND METHODS We retrospectively reviewed patients who underwent surgery for MTLE. Three clinicians identified the side of MTLE epileptogenesis by visual inspection. The surgical side was set as the epileptogenic side. Two parcellation paradigms and corresponding atlases (Automated Anatomical Labeling and FreeSurfer aparc + aseg) were used to extract the normalized PET uptake of the regions of interest (ROIs). The lateralization index of the MTLE-associated regions in either hemisphere was calculated. The lateralization indices of each ROI were subjected for machine learning to establish the model for classifying the side of MTLE epileptogenesis. RESULT Ninety-three patients were enrolled for training and validation, and another 11 patients were used for testing. The hit rate of lateralization by visual analysis was 75.3%. Among the 23 patients whose MTLE side of epileptogenesis was incorrectly determined or for whom no conclusion was reached by visual analysis, the Automated Anatomical Labeling and aparc + aseg parcellated the associated ROIs on the correctly lateralized MTLE side in 100.0% and 82.6%. In the testing set, lateralization accuracy was 100% in the 2 paradigms. CONCLUSIONS Visual analysis of 18F-FDG PET to lateralize MTLE epileptogenesis showed a lower hit rate compared with machine-assisted interpretation. While reviewing 18F-FDG PET images of MTLE patients, considering the regions associated with MTLE resulted in better performance than limiting analysis to hippocampal regions.
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Affiliation(s)
- Yen-Cheng Shih
- From the Department of Neurology, Neurological Institute, Taipei Veterans General Hospital
- School of Medicine, National Yang Ming Chiao Tung University College of Medicine
- Brain Research Center, National Yang Ming Chiao Tung University
| | - Tse-Hao Lee
- School of Medicine, National Yang Ming Chiao Tung University College of Medicine
- Departments of Nuclear Medicine
| | - Hsiang-Yu Yu
- From the Department of Neurology, Neurological Institute, Taipei Veterans General Hospital
- School of Medicine, National Yang Ming Chiao Tung University College of Medicine
- Brain Research Center, National Yang Ming Chiao Tung University
| | - Chien-Chen Chou
- From the Department of Neurology, Neurological Institute, Taipei Veterans General Hospital
- School of Medicine, National Yang Ming Chiao Tung University College of Medicine
- Brain Research Center, National Yang Ming Chiao Tung University
| | - Cheng-Chia Lee
- School of Medicine, National Yang Ming Chiao Tung University College of Medicine
- Brain Research Center, National Yang Ming Chiao Tung University
- Neurosurgery, Neurological Institute, Taipei Veterans General Hospital
| | - Po-Tso Lin
- From the Department of Neurology, Neurological Institute, Taipei Veterans General Hospital
- School of Medicine, National Yang Ming Chiao Tung University College of Medicine
- Brain Research Center, National Yang Ming Chiao Tung University
| | - Syu-Jyun Peng
- Professional Master Program in Artificial Intelligence in Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
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Gaviria Carrillo M, López J, Rodríguez Q. JH, Gaona I, Ortiz-Guerrero G, Nava-Mesa MO. Apparent False Lateralization of Seizure Onset by Scalp EEG in Temporal Lobe Epilepsy Associated with Cerebral Cavernous Malformation: A Case Report and Overview. Brain Sci 2020; 10:brainsci10090584. [PMID: 32846994 PMCID: PMC7565586 DOI: 10.3390/brainsci10090584] [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: 07/09/2020] [Revised: 08/11/2020] [Accepted: 08/13/2020] [Indexed: 11/16/2022] Open
Abstract
False lateralization of ictal onset by scalp electroencephalogram (EEG) is an infrequent entity that has been reported in patients with mesial temporal lobe epilepsy associated with hippocampal sclerosis (HS). In these cases, a tendency for rapid seizures that spread through the frontal-limbic system and hippocampal commissural pathways to the contralateral hemisphere has been proposed. Cerebral cavernous malformations (CCMs), which constitute a collection of abnormally configured small blood vessels with irregular structures, is a well-defined epilepsy-associated pathology. Their primary association with seizures might be explained either as a result of physiological changes affecting the cerebral cortex immediately surrounding the CCM (an epileptogenic mechanism that is relevant for both, temporal and extratemporal lesions) or as a result of promoting epileptogenicity in remote but anatomo-functionally connected brain regions, a mechanism that is particularly relevant for temporal lobe lesions. To date, there have been only two publications on falsely lateralizing ictal onsets by EEG in temporal cavernoma, but not in other regions. Here, we report a rare case of apparent false lateralization of ictal onset by scalp EEG in a patient with a left medial frontal gyrus cavernoma (supplementary motor area), and discuss some relevant pathophysiological mechanisms of false lateralization.
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Affiliation(s)
- Mariana Gaviria Carrillo
- Department of Neurology, Fundación Cardioinfantil (FCI), Bogotá 110131, Colombia; (M.G.C.); (J.H.R.Q.); (I.G.)
- Escuela de Medicina y Ciencias de la Salud, GI en Neurociencias-NeURos, Universidad del Rosario, Bogotá 111221, Colombia
| | - Jonathan López
- Department of Neurology, Universidad del Sinú, Cartagena 130001, Colombia;
| | - Jesús H. Rodríguez Q.
- Department of Neurology, Fundación Cardioinfantil (FCI), Bogotá 110131, Colombia; (M.G.C.); (J.H.R.Q.); (I.G.)
- Escuela de Medicina y Ciencias de la Salud, GI en Neurociencias-NeURos, Universidad del Rosario, Bogotá 111221, Colombia
- Department of Neurology, Hospital Universitario Mayor—Mederi, Bogotá 111411, Colombia
| | - Ivan Gaona
- Department of Neurology, Fundación Cardioinfantil (FCI), Bogotá 110131, Colombia; (M.G.C.); (J.H.R.Q.); (I.G.)
| | - Gloria Ortiz-Guerrero
- Department of Neurology, University of Kansas Medical Center, Kansas City, KS 66160, USA;
| | - Mauricio O. Nava-Mesa
- Escuela de Medicina y Ciencias de la Salud, GI en Neurociencias-NeURos, Universidad del Rosario, Bogotá 111221, Colombia
- Correspondence: or ; Tel.: +571-2970200 (ext. 3354)
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Hartl E, Rémi J, Vollmar C, Goc J, Loesch AM, Rominger A, Noachtar S. PET imaging in extratemporal epilepsy requires consideration of electroclinical findings. Epilepsy Res 2016; 125:72-6. [DOI: 10.1016/j.eplepsyres.2016.05.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Revised: 04/19/2016] [Accepted: 05/25/2016] [Indexed: 11/27/2022]
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Abstract
Imaging is pivotal in the evaluation and management of patients with seizure disorders. Elegant structural neuroimaging with magnetic resonance imaging (MRI) may assist in determining the etiology of focal epilepsy and demonstrating the anatomical changes associated with seizure activity. The high diagnostic yield of MRI to identify the common pathological findings in individuals with focal seizures including mesial temporal sclerosis, vascular anomalies, low-grade glial neoplasms and malformations of cortical development has been demonstrated. Positron emission tomography (PET) is the most commonly performed interictal functional neuroimaging technique that may reveal a focal hypometabolic region concordant with seizure onset. Single photon emission computed tomography (SPECT) studies may assist performance of ictal neuroimaging in patients with pharmacoresistant focal epilepsy being considered for neurosurgical treatment. This chapter highlights neuroimaging developments and innovations, and provides a comprehensive overview of the imaging strategies used to improve the care and management of people with epilepsy.
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Subclinical Seizures as a Pitfall in 18F-FDG PET Imaging of Temporal Lobe Epilepsy. Clin Nucl Med 2014; 39:819-21. [DOI: 10.1097/rlu.0000000000000444] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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11C-Methionine uptake in secondary brain epilepsy. Rev Esp Med Nucl Imagen Mol 2014. [DOI: 10.1016/j.remnie.2014.06.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Lopci E, Bello L, Chiti A. (11)C-Methionine uptake in secondary brain epilepsy. Rev Esp Med Nucl Imagen Mol 2014; 33:234-6. [PMID: 24630372 DOI: 10.1016/j.remn.2013.12.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Revised: 12/12/2013] [Accepted: 12/16/2013] [Indexed: 11/25/2022]
Abstract
Carbon-11 methionine ((11)C-Methionine) is a radio-labeled amino acid currently utilized in Positron Emission Tomography (PET) for imaging primary and metastatic brain tumors. Its clinical use relies mostly on oncologic applications, but the tracer has the potential to investigate other non-malignant conditions. So far, very limited evidence concerns the use of (11)C-Methionine in patients suffering from seizure; however, the tracer can find a proper utilization in this setting especially as a diagnostic complement to (18)F-Fluorodeoxyglucose ((18)F-FDG). Herein we report the case of a 57-year-old patient presenting with epileptic crises secondary to a brain metastasis from bladder carcinoma, who was investigated in our institution with (11)C-Methionine PET. The scan documented the disease recurrence in the left parietal lobe associated with a diffused tracer uptake in the surrounding cerebral circumvolutions, derived from the comitial status. After surgical removal of the metastatic lesion, the patient experienced a complete recovery of symptoms and no further onset of secondary seizure.
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Affiliation(s)
- E Lopci
- Nuclear Medicine, Humanitas Clinical and Research Center, Rozzano, MI, Italy.
| | - L Bello
- Neurosurgery, Humanitas Clinical and Research Center, Rozzano, MI, Italy
| | - A Chiti
- Nuclear Medicine, Humanitas Clinical and Research Center, Rozzano, MI, Italy
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Hur YJ, Lee JS, Lee JD, Yun MJ, Kim HD. Quantitative analysis of simultaneous EEG features during PET studies for childhood partial epilepsy. Yonsei Med J 2013; 54:572-7. [PMID: 23549798 PMCID: PMC3635630 DOI: 10.3349/ymj.2013.54.3.572] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
PURPOSE To demonstrate the significance of simultaneous electroencephalography (EEG) recording during 2-deoxy-2-[(18)F] fluoro-D-glucose (FDG)-positron emission tomography (PET) in childhood partial epilepsy. MATERIALS AND METHODS We included 46 children with partial epilepsy who underwent simultaneous EEG during PET. We compared the epileptogenic area of several EEG features including epileptiform discharges, focal polymorphic slow waves, and electrographic seizures, with the abnormal metabolic region on PET. We also compared the epileptogenic area of simultaneous EEG and PET with findings on magnetic resonance imaging (MRI) and video/EEG, as well as the histopathological diagnosis of the resected cortical area, in eight patients who underwent surgical resection of the epileptogenic area. RESULTS Hypometabolic regions on interictal PET were concordant with epileptogenic areas of epileptiform discharges and focal polymorphic slow waves, according to their frequency and/or severity, with odds ratios of 1.35 and 1.81, respectively (p<0.05). Hypermetabolic PET was also concordant with epileptogenic areas of ictal events longer than 20 seconds during the period of FDG uptake. Among the eight patients who underwent surgical resection, six patients, including two with non-lesional MRI, had concordant EEG and PET findings, were confirmed pathologically, and became seizure-free after surgery. CONCLUSION Simultaneous EEG is useful in identifying epileptogenic areas due to a high concordance with abnormal PET metabolic areas. Moreover, simultaneous EEG may also prevent false lateralization of PET from postictal and mixed metabolism during ictal events, as well as abnormal hypermetabolism, during frequent interictal epileptiform discharges.
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Affiliation(s)
- Yun Jung Hur
- Department of Pediatrics, Haeundae Paik Hospital, Inje University College of Medicine, Busan, Korea
- Department of Medicine, The Graduate School, Yonsei University, Seoul, Korea
| | - Joon Soo Lee
- Division of Pediatric Neurology, Department of Pediatrics, Pediatric Epilepsy Clinic, Severance Children's Hospital, Epilepsy Research Institute, Yonsei University College of Medicine, Seoul, Korea
| | - Jong Doo Lee
- Department of Radiology, Yonsei University College of Medicine, Seoul, Korea
| | - Mi Jin Yun
- Department of Radiology, Yonsei University College of Medicine, Seoul, Korea
| | - Heung Dong Kim
- Division of Pediatric Neurology, Department of Pediatrics, Pediatric Epilepsy Clinic, Severance Children's Hospital, Epilepsy Research Institute, Yonsei University College of Medicine, Seoul, Korea
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Kumar A, Semah F, Chugani HT, Theodore WH. Epilepsy diagnosis: positron emission tomography. HANDBOOK OF CLINICAL NEUROLOGY 2012; 107:409-24. [PMID: 22938986 DOI: 10.1016/b978-0-444-52898-8.00026-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Ajay Kumar
- Department of Pediatrics & Neurology, Children's Hospital of Michigan, Detroit, MI, USA
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Is sleep-related consolidation impaired in focal idiopathic epilepsies of childhood? A pilot study. Epilepsy Behav 2011; 22:380-4. [PMID: 21872533 DOI: 10.1016/j.yebeh.2011.07.023] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2011] [Revised: 06/29/2011] [Accepted: 07/18/2011] [Indexed: 11/20/2022]
Abstract
We investigated sleep-related declarative memory consolidation in four children with focal idiopathic epilepsy. In a population of healthy control children, recall of learned pairs of words was increased after a night of sleep, but not after a daytime wakefulness period. In children with epilepsy (1 case of benign epilepsy with centro-temporal spikes, 1 case of benign childhood epilepsy with occipital paroxysms, and 2 cases of epileptic encephalopathy (EE) with continuous spike and waves during slow-wave sleep, CSWS), recall performance significantly decreased overnight, suggesting impairment in sleep-related declarative memory consolidation. Hydrocortisone treatment in one patient with EE with CSWS resulted in normalization of the sleep EEG together with normalization of overnight memory performance, which was not the case in the other EE/CSWS patient whose sleep EEG was only partially improved. These preliminary results suggest that interictal epileptiform discharges in idiopathic focal epilepsies may disrupt the brain processes underlying sleep-related memory consolidation.
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Presurgical epilepsy localization with interictal cerebral dysfunction. Epilepsy Behav 2011; 20:194-208. [PMID: 21257351 DOI: 10.1016/j.yebeh.2010.12.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2010] [Accepted: 12/07/2010] [Indexed: 11/22/2022]
Abstract
Localization of interictal cerebral dysfunction with 2-[(18)F]fluoro-2-D-deoxyglucose (FDG) positron emission tomography (PET) and neuropsychological examination usefully supplements electroencephalography (EEG) and brain magnetic resonance imaging (MRI) in planning epilepsy surgery. In MRI-negative mesial temporal lobe epilepsy, correlation of temporal lobe hypometabolism with extracranial ictal EEG can support resection without prior intracranial EEG monitoring. In refractory localization-related epilepsies, hypometabolic sites may supplement other data in hypothesizing likely ictal onset zones in order to intracranial electrodes for ictal recording. Prognostication of postoperative seizure freedom with FDG PET appears to have greater positive than negative predictive value. Neuropsychological evaluation is critical to evaluating the potential benefit of epilepsy surgery. Cortical deficits measured with neuropsychometry are limited in lateralizing and localizing value for determination of ictal onset sites, however. Left temporal resection risks iatrogenic verbal memory deficits and dysnomia, and neuropsychological findings are useful in predicting those at greatest risk. Prognostication of cognitive risks with resection at other sites is less satisfactory.
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Giovacchini G, Squitieri F, Esmaeilzadeh M, Milano A, Mansi L, Ciarmiello A. PET translates neurophysiology into images: A review to stimulate a network between neuroimaging and basic research. J Cell Physiol 2011; 226:948-61. [DOI: 10.1002/jcp.22451] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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Lee KK, Salamon N. [18F] fluorodeoxyglucose-positron-emission tomography and MR imaging coregistration for presurgical evaluation of medically refractory epilepsy. AJNR Am J Neuroradiol 2009; 30:1811-6. [PMID: 19628624 DOI: 10.3174/ajnr.a1637] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Epilepsy is a chronic disorder affecting approximately 1% of the population of the world. Approximately one third of patients with epilepsy remain refractory to medical therapy. For these patients, surgery is a curative option. In order for surgery to be considered, precise localization of the structural abnormality is needed. When MR imaging findings are normal, more sensitive techniques such as positron-emission tomography (PET) can help find the abnormality. Combining MR imaging and PET information increases the sensitivity of the presurgical evaluation. In this review, we discuss the clinical applications of coregistration of [(18)F] fluorodeoxyglucose (FDG)-PET with MR imaging for medically refractory epilepsy. Because FDG-PET/MR imaging coregistration has been a routine component of the presurgical evaluation for patients with epilepsy at our institution since 2004, we also included cases from our data base that exemplify the utility of this technology to obtain better postsurgical outcomes.
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Affiliation(s)
- K K Lee
- Department of Radiology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
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Becker Junior V, Wichert-Ana L, Silva RPLFD, Abud DG, Escorsi-Rosset S, Romcy-Pereira R, Leite JP. Neurovascular coupling and functional neuroimaging in epilepsy. ACTA ACUST UNITED AC 2009. [DOI: 10.1590/s1676-26492009000100007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
INTRODUCTION: The neural regulation of the microcirculation is done by the functional neurovascular unit that is composed of vascular, astroglial and neuronal cells. The neurovascular unit represents the interface between the Central Nervous System and the Vascular System. OBJECTIVE: This paper reviews the literature on functional neuroimaging with a particular focus on the mechanisms of the neurovascular coupling. CONCLUSIONS: Functional neuroimaging techniques as functional MRI, SPECT and PET distinguish metabolic and physiological processes underlying normal and abnormal events, based on neurovascular coupling. Although these techniques still have limitations in temporal and spatial resolution, they have considerably reduced the need for intracranial electrodes or invasive functional tests in the presurgical evaluation for intractable epilepsy. Recently, new techniques as optical approaches (measurement of intrinsic optical signals and near infrared spectroscopy) have increased both temporal and spatial resolutions. The use of such techniques in animal models has yielded experimental evidence for a neurovascular coupling in normal and epileptic conditions.
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Hur YJ, Lee JS, Lee JD, Kim HD. Analysis on the association between EEG and 2-deoxy-2-[18F]-D-glucose (FDG)-PET findings in children with epilepsy. KOREAN JOURNAL OF PEDIATRICS 2008. [DOI: 10.3345/kjp.2008.51.3.286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Yun Jung Hur
- Department of Pediatrics, Yonsei University College of Medicine, Seoul, Korea
| | - Joon Soo Lee
- Department of Pediatrics, Yonsei University College of Medicine, Seoul, Korea
| | - Jong Doo Lee
- Department of Radiology, Yonsei University College of Medicine, Seoul, Korea
| | - Heung Dong Kim
- Department of Pediatrics, Yonsei University College of Medicine, Seoul, Korea
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Willmann O, Wennberg R, May T, Woermann FG, Pohlmann-Eden B. The contribution of 18F-FDG PET in preoperative epilepsy surgery evaluation for patients with temporal lobe epilepsy. Seizure 2007; 16:509-20. [PMID: 17532231 DOI: 10.1016/j.seizure.2007.04.001] [Citation(s) in RCA: 163] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2006] [Revised: 04/06/2007] [Accepted: 04/16/2007] [Indexed: 11/17/2022] Open
Abstract
OBJECTIVE To assess the predictive diagnostic added value of positron emission tomography (PET) in preoperative epilepsy surgery evaluation for patients with temporal lobe epilepsy (TLE). METHODS A meta-analysis of publications from 1992 to 2006 was performed. Forty-six studies were identified that met inclusion criteria presenting detailed diagnostic test results and a classified postoperative outcome. Studies exclusively reporting on patients with brain tumors or on children were excluded. RESULTS The analyses were complicated by significant differences in study design and often by lack of precise patient data. Ipsilateral PET hypometabolism showed a predictive value of 86% for good outcome. The predictive value was 80% in patients with normal MRI and 72% in patients with non-localized ictal scalp EEG. In a selected population of 153 TLE patients with a follow-up of >12 months PET correlated well with other non-invasive diagnostic tests, but none of the odds ratios of any test combination was significant. CONCLUSION Our data confirm that ipsilateral PET hypometabolism may be an indicator for good postoperative outcome in presurgical evaluation of drug-resistant TLE, although the actual diagnostic added value remained questionable and unclear. PET does not appear to add value in patients localized by ictal scalp EEG and MRI. Prospective studies limited to non-localized ictal scalp EEG or MRI-negative patients are required for validation.
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Affiliation(s)
- O Willmann
- Department of Neurology, University Hospital Mannheim, University of Heidelberg, Germany
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Weitemeyer L, Kellinghaus C, Weckesser M, Matheja P, Loddenkemper T, Schuierer G, Schober O, Ringelstein EB, Lüdemann P. The Prognostic Value of [18F]FDG-PET in Nonrefractory Partial Epilepsy. Epilepsia 2005; 46:1654-60. [PMID: 16190939 DOI: 10.1111/j.1528-1167.2005.00258.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
PURPOSE Regional abnormalities of cerebral glucose metabolism, as identified by 18-fluorodeoxyglucose positron emission tomography (FDG-PET) have prognostic value regarding the outcome of epilepsy surgery in patients with refractory partial epilepsy. The value of FDG-PET abnormalities in nonrefractory patients has not been investigated systematically. This study examines whether FDG-PET could be used for early identification of nonrefractory epilepsy in patients who will become pharmacoresistant later during the course of their disease. METHODS We investigated interictal abnormalities of cerebral glucose metabolism by using FDG-PET in 125 consecutive patients with nonrefractory cryptogenic partial epilepsy and normal cranial magnetic resonance imaging (MRI), and we compared relative changes in seizure frequency in 90 patients after > or =2 years of follow-up. RESULTS Regional asymmetry of tracer distribution was seen in 43 of the 90 patients. Forty-one patients had regional glucose hypometabolism in the temporal and two patients in an extratemporal region. No difference between patients with and without a hypometabolic focus was found regarding seizure freedom after follow-up. This held true also for the subgroup of patients with epilepsy onset within 1 year before admission. Only patients with regional glucose metabolism showed an increase in seizure frequency. Multivariate analysis showed that only anticonvulsive treatment before index admission and the possibility of localizing the epileptogenic focus by using all available clinical and EEG data were independently associated with continuing seizures after a median follow-up period of 43 months. CONCLUSIONS Regional hypometabolism in FDG-PET is not significantly associated with a lower likelihood of successful anticonvulsant drug therapy in patients with nonrefractory partial epilepsy. Careful analysis of all routinely available clinical and neurophysiologic data has a much better predictive power to identify patients with medically refractory epilepsy early in the course of the disease. However, if PET data are available, they could help in identifying patients with a less benign course.
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Affiliation(s)
- Lars Weitemeyer
- Department of Neurology, University of Münster, Münster, Germany
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Abstract
The role of molecular neuroimaging techniques is increasing in the understanding of pathophysiological mechanism of diseases. To date, positron emission tomography is the most powerful tool for the non-invasive study of biochemical and molecular processes in humans and animals in vivo. With the development in radiochemistry and tracer technology, a variety of endogenously expressed and exogenously introduced genes can be analyzed by PET. This opens up the exciting and rapidly field of molecular imaging, aiming at the non-invasive localisation of a biological process of interest in normal and diseased cells in animal models and humans in vivo. Besides its usefulness for basic research positron emission tomography has been proven to be superior to conventional diagnostic methods in several clinical indications. This is illustrated by detection of biological or anatomic changes that cannot be demonstrated by computed tomography or magnetic resonance imaging, as well as even before symptoms are expressed. The present review summarizes the clinical use of positron emission tomography in neuroscience that has helped elucidate the pathophysiology of a number of diseases and has suggested strategies in the treatment of these patients. Special reference is given to the neurovascular, neurodegenerative and neurooncological disease.
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Affiliation(s)
- B Schaller
- Max-Planck-Institut für Neurologische Forschung, Köln
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Henry TR, Votaw JR. The role of positron emission tomography with [18F]fluorodeoxyglucose in the evaluation of the epilepsies. Neuroimaging Clin N Am 2004; 14:517-35, ix. [PMID: 15324862 DOI: 10.1016/j.nic.2004.04.011] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Cerebral glucose metabolic mapping using positron emission tomography (PET) and 2-[18F]fluoro-2-deoxyglucose (FDG) has been extensively studied in the epilepsies. Regions of interictal glucose hypometabolism are highly associated with cerebral sites of seizure generation-propagation in focal epilepsies. The volume of reduced glucose metabolism is often widespread and even bilateral in focal epilepsies, although ictal onset zones typically are located at the sites of most severe hypometabolism within a larger volume of hypometabolism.
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Affiliation(s)
- Thomas R Henry
- Department of Neurology, Emory University School of Medicine, Woodruff Memorial Building, Suite 6000, PO Drawer V, 1639 Pierce Drive, Atlanta, GA 30322, USA.
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Novak L, Emri M, Molnar P, Balkay L, Lengyel Z, Tron L. Subcortical [18F]fluorodeoxyglucose uptake in lesional epilepsy in patients with intracranial tumour. Nucl Med Commun 2004; 25:123-8. [PMID: 15154699 DOI: 10.1097/00006231-200402000-00005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
BACKGROUND We hypothesized that in patients with intracerebral tumours a subcortical metabolical shift may be present when the underlying pathology can, itself, be the epileptogenic focus. We also assumed that by studying the alterations in glucose metabolism beyond the tumour's borders we could identify a modulator area. METHODS Sixty-seven patients with supratentorial brain tumour associated epilepsy were investigated interictally, in normoglycaemic conditions, by using [18F]fluorodeoxyglucose positron emission tomography (FDG PET). The studies were analysed semiquantitatively by calculating standardized uptake values and asymmetry indices. Normal subjects and patients with non-epileptic brain lesions were used as controls. RESULTS Compared to normal controls frontal and temporal tumours showed significant changes in thalamic FDG uptake, which reflected hypometabolism of the affected side. It was noted in occipito-medial cortex in temporal tumours and in lentiform nucleus in frontal tumours as well. Comparison to lesional brains only proved that there was significant hypometabolism in lentiform nucleus in temporal tumours. CONCLUSIONS The quantified values obviously reflect biological changes. The observed subcortical hypometabolism is most likely secondary to underlying pathology. Although seizures in tumorous patients do not originate from subcortical structures their influence on cortical sites of seizure initiation could be explained by defective subcortical regulation of cortical excitability.
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Affiliation(s)
- Laszlo Novak
- Department of Neurosurgery, Health and Life Sciences Center, University of Debrecen, Hungary.
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23
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Akanuma N, Koutroumanidis M, Adachi N, Alarcón G, Binnie CD. Presurgical assessment of memory-related brain structures: the Wada test and functional neuroimaging. Seizure 2003; 12:346-58. [PMID: 12915080 DOI: 10.1016/s1059-1311(02)00323-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Medial temporal lobe structures are known to play a major role in memory processing. Recent work has revealed that extratemporal structures (e.g. the frontal lobe and thalamus) may also be important in memory function. In candidates for epilepsy surgery, particularly in those with temporal lobe seizures, presurgical evaluation of memory function is essential, since seizures may originate in the neural substrate that is critical for memory. In this article, we review the tools used for presurgical evaluation and their contribution to the understanding of memory function, focusing on the Wada test, [18F]fluorodeoxy-glucose positron emission tomography ([18F]FDG-PET) and functional magnetic resonance imaging (fMRI). We also explore perspectives on future studies that may elucidate the role of the temporal and extratemporal structures in memory function and the mechanisms of cerebral plasticity.
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Affiliation(s)
- Nozomi Akanuma
- Department of Clinical Neuroscience, Guy's, King's and St. Thomas' School of Medicine, King's College London, London, UK.
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24
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Henry TR, Van Heertum RL. Positron emission tomography and single photon emission computed tomography in epilepsy care. Semin Nucl Med 2003; 33:88-104. [PMID: 12756642 DOI: 10.1053/snuc.2003.127301] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Radiopharmaceutical brain imaging is clinically applied in planning resective epilepsy surgery. Cerebral sites of seizure generation-propagation are highly associated with regions of hyperperfusion during seizures, and with glucose hypometabolism interictally. For surgical planning in epilepsy, the functional imaging modalities currently established are ictal single photon emission computed tomography (SPECT) with [(99m)Tc]technetium-hexamethylpropyleneamine oxime (HMPAO) or with [(99m)Tc]technetium-ethylene cysteine dimer (ECD), and interictal positron emission tomography (PET) with 2-[(18)F]fluoro-2-deoxyglucose (FDG). Ictal SPECT and interictal FDG PET can be used in presurgical epilepsy evaluations to reliably: (1) determine the side of anterior temporal lobectomy, and in children the area of multilobar resection, without intracranial electroencephalographic recording of seizures; (2) select high-probability sites of intracranial electrode placement for recording ictal onsets; and, (3) determine the prognosis for complete seizure control following anterior temporal lobe resection. Coregistration of a patient's structural (magnetic resonance) and functional images, and statistical comparison of a patient's data with a normal data set, can increase the sensitivity and specificity of these SPECT and PET applications to the presurgical evaluation.
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Affiliation(s)
- Thomas R Henry
- Emory Epilepsy Center, Department of Neurology, Emory University School of Medicine, Atlanta, GA, USA
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25
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Abstract
Neuroimaging is one of the most important advances made in the past decade in the management of seizure disorders. Magnetic resonance imaging (MRI) has increased substantially the ability to detect causes of seizure disorders, to plan medical or surgical therapy, and to prognosticate the outcome of disorders and therapy. However, MRI must be performed with techniques that will maximize the detection of potentially epileptogenic lesions, especially in candidates for epilepsy surgery. Functional imaging has an established role in evaluating patients for epilepsy surgery. It is relied on when results from standard diagnostic methods, such as clinical information, electroencephalography, and MRI, are insufficient to localize the seizure focus. Also, functional imaging is a reportedly reliable alternative to invasive methods for identifying language, memory, and sensorimotor areas of the cerebral cortex. Despite the availability of multimodality imaging, the epileptogenic zone is not determined solely by a single imaging modality. Evidence and experience have shown that concordance of results from clinical, electrophysiologic, and neuroimaging studies is needed to identify the epileptogenic zone accurately. With modern techniques in image processing, multimodality imaging can integrate the location of abnormal electroencephalographic, structural, and functional imaging foci on a "map" of the patient's brain. Computer image-guided surgery allows surgically exact implantation of intracranial electrodes and resection of abnormal structural or functional imaging foci. These techniques decrease the risk of morbidity associated with epilepsy surgery and enhance the probability of postsurgical seizure control.
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Affiliation(s)
- Elson L So
- Department of Neurology, Mayo Clinic, Rochester, Minn 55905, USA
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26
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Ryvlin P, Mauguière F. [Neurofunctional tests in presurgical strategies for partial epilepsies]. ANNALES FRANCAISES D'ANESTHESIE ET DE REANIMATION 2001; 20:123-36. [PMID: 11270234 DOI: 10.1016/s0750-7658(01)00349-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The presurgical evaluation of drug-resistant partial epilepsies primarily relies on two major investigations, including a long term video-EEG monitoring which aimed at recording the patient's typical seizures, and a specifically designed high quality magnetic resonance imaging (MRI). The latter demonstrates an abnormality within the epileptogenic lobe in the majority of cases, which might not, however, necessarily match the epileptogenic zone. Numerous functional neuro-imaging techniques have been progressively added to the pre-surgical evaluation of refractory partial epilepsies, such as the study of cerebral glucose metabolism, benzodiazepine receptor availability, and methionine incorporation using positron emission tomography (PET), the evaluation of ictal cerebral blood flow changes using single photon emission computerized tomography (SPECT), the measurement of N-acetyl-aspartate concentration with magnetic resonance spectroscopy, and the mapping of eloquent areas using functional MRI. These investigations can help to confirm the origin of seizure onset previously suggested by MRI and electro-clinical data, and provide independent prognostic information regarding the chance of a successful surgical treatment. Moreover, functional neuro-imaging data can have a critical diagnostic value when MRI is strictly normal or shows multifocal abnormalities. However, the variety and rapid evolution of functional neuro-imaging techniques makes it difficult to propose a standard protocol. Finally, it remains mandatory to proceed to an intracranial EEG investigation in a substantial number of patients, including the majority of those suffering from an extra-temporal epilepsy.
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Affiliation(s)
- P Ryvlin
- Service de neurologie fonctionnelle et d'épileptologie, hôpital neurologique, BP Lyon-Montchat, 69394 Lyon, France
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27
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Abstract
Four patients with complex partial seizure disorder whose positron emission tomography (PET) scans show sustained hyperperfusion of the epileptiform focus 12-24 h after a seizure episode are presented. Three of these patients underwent same day Fluorine-18 (18F) deoxyglucose (FDG) PET scans, which showed hypometabolism of the epileptic temporal lobe. In one patient who underwent repeated blood flow and concurrent glucose metabolism scans 4 days after a seizure, hyperperfusion was not present and the FDG-PET demonstrated hypometabolism. Persistent hyperperfusion was noted in six out of 65 cases studied. Four out of six patients who were followed clinically were presented in this report. The cause of the rare occurrence of persistent postictal or interictal hyperperfusion and the differences of postictal blood flow dynamics and glucose metabolism need to be clarified further with future studies.
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Affiliation(s)
- R Tatlidil
- Research Imaging Center, University of Texas Health Sciences Center, San Antonio, TX, USA
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28
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Van Bogaert P, Massager N, Tugendhaft P, Wikler D, Damhaut P, Levivier M, Brotchi J, Goldman S. Statistical parametric mapping of regional glucose metabolism in mesial temporal lobe epilepsy. Neuroimage 2000; 12:129-38. [PMID: 10913319 DOI: 10.1006/nimg.2000.0606] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We investigated statistical parametric mapping (SPM) use for positron emission tomography (PET) with [(18)F]fluorodeoxyglucose (FDG) data analysis in mesial temporal lobe epilepsy. The study involved 14 patients with temporal lobe epilepsy ultimately treated by anterior temporal lobectomy. Surgical outcome in terms of seizure control was favorable in 12 patients. Two different SPM approaches were designed to analyze each FDG-PET scan: a direct comparison with a control group (n = 27) and a search for significant interhemispheric asymmetry considering the asymmetry existing in the control group. Statistical inference was performed, first, without correction for multiple comparisons (making the hypothesis of temporal hypometabolism) and, second, after correction for multiple comparisons. Search for temporal interhemispheric asymmetry under the hypothesis of temporal hypometabolism was the most reliable SPM approach: hypometabolism was identified on the side chosen for resection in most cases (sensitivity, 71%; specificity, 100%) and was predictive of favorable postsurgical outcome in 90% of the patients. There was no false-positive result within the control group using this approach. After correction for multiple comparisons, SPM also identified in some patients temporal hypermetabolic areas as well as extratemporal cortical and subcortical hypometabolic areas on the side of resection but also on the contralateral side. In a further step, SPM was used for a group analysis of patients with favorable outcome after reversing scans when needed to set an identical lateralization in all patients. This analysis identified multiple ipsilateral temporal and extratemporal hypometabolic regions; when temporal metabolic changes were specifically assessed, the contralateral mesiotemporal region was found hypermetabolic, possibly as a manifestation of compensatory mechanisms in the presence of a unilateral epileptogenic lesion.
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Affiliation(s)
- P Van Bogaert
- PET-Biomedical Cyclotron Unit, Université Libre de Bruxelles, Brussels, Belgium
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29
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Juhász C, Chugani DC, Muzik O, Watson C, Shah J, Shah A, Chugani HT. Relationship between EEG and positron emission tomography abnormalities in clinical epilepsy. J Clin Neurophysiol 2000; 17:29-42. [PMID: 10709809 DOI: 10.1097/00004691-200001000-00004] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Positron emission tomography (PET) is a relatively noninvasive neuroimaging method by means of which a large variety of human brain functions can be assessed. Localized neurochemical abnormalities detected by PET were found in patients with partial epilepsy and suggested the use of this modality for localizing epileptogenic regions of the brain. The clinical usefulness of PET is determined by its sensitivity and specificity for identifying epileptogenic areas as defined by ictal surface and intracranial EEG recordings. The findings obtained from comparative EEG and glucose PET data are reviewed with special emphasis on patients undergoing presurgical evaluation because of medically intractable temporal and extratemporal lobe epilepsy. The utility of glucose PET studies for identifying regions of seizure onset is presented, and the limited specificity of glucose metabolic abnormalities for the detection of various EEG patterns in clinical epilepsy is discussed. The authors review the available intracranial EEG and PET comparisons using [11C]flumazenil (FMZ) PET, a tracer for the assessment of tau-amino-butyric acid/benzodiazepine receptor function. They also summarize their experience with [11C]flumazenil PET in identifying cortical regions that show various ictal and interictal cortical EEG abnormalities in patients with extratemporal seizure origin. Finally, the authors demonstrate that further development of new PET tracers, such as alpha-[11C]methyl-L-tryptophan, is feasible and clinically useful and may increase the number of patients in whom PET studies can replace invasive EEG monitoring.
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Affiliation(s)
- C Juhász
- Department of Pediatrics, Children's Hospital of Michigan, Detroit Medical Center, Wayne State University School of Medicine, 48201, USA
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30
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Iacoboni M, Baron JC, Frackowiak RS, Mazziotta JC, Lenzi GL. Emission tomography contribution to clinical neurology. Clin Neurophysiol 1999; 110:2-23. [PMID: 10348316 DOI: 10.1016/s0013-4694(98)00097-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The role of functional neuroimaging techniques in furthering the understanding of pathophysiological mechanisms of neurological diseases and in the assessment of neurological patients is increasingly important. Here, we review data mainly from emission tomography techniques, namely positron emission tomography (PET) and single photon emission computerized tomography (SPECT), that have helped elucidate the pathophysiology of a number of neurological diseases and have suggested strategies in the treatment of neurological patients. We also suggest possible future developments of functional neuroimaging applied to clinical populations and briefly touch on the emerging role of functional magnetic resonance imaging (fMRI) in clinical neurology and neurosurgery.
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Affiliation(s)
- M Iacoboni
- Brain Mapping Division, Neuropsychiatric Institute, UCLA School of Medicine, University of California, Los Angeles 90033, USA
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31
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Abstract
Neuroimaging techniques have improved the understanding, diagnosis, and management of epilepsy. By providing excellent structural information, MRI is the technique of choice in evaluating patients with epilepsy. Functional imaging techniques, including MR spectroscopy, functional MRI, positron emission tomography, and single photon emission CT, permit noninvasive assessment of the epileptic substrate, its functional status, and neuroreceptors. The MRI-based techniques will potentially assume a greater role in the cost-effective workup of the patient. Currently, newer techniques such as magnetoencephalography, magnetic source imaging, and optical imaging are research tools.
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Affiliation(s)
- Y Y Sitoh
- Department of Diagnostic Imaging, Tan Tock Seng Hospital, Singapore
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32
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33
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Theodore WH, Sato S, Kufta CV, Gaillard WD, Kelley K. FDG-positron emission tomography and invasive EEG: seizure focus detection and surgical outcome. Epilepsia 1997; 38:81-6. [PMID: 9024188 DOI: 10.1111/j.1528-1157.1997.tb01081.x] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
PURPOSE To study the value of [18F]2-deoxyglucose (FDG)-positron emission tomography when surface ictal EEG is nonlocalizing. METHODS FDG-PET scans were performed in 46 patients with complex partial seizures (CPS) not localized by ictal surface-sphenoidal video-EEG (VEEG) telemetry. Interictal PET was performed with continuous EEG monitoring, and images were analyzed with a standard template. Forty patients subsequently had subdural and 6 had depth electrodes (invasive EEG, IEEG); 22 had bilateral implants. A focus was detected in 40, and 35 had temporal lobectomy based on IEEG localization. RESULTS There was a close association between IEEG and PET localization (p < 0.01): 26 patients had relative unilateral temporal FDG-PET hypometabolism, all had congruent IEEG, and 18 of 23 were seizure-free after temporal lobectomy. Five patients had unilateral frontotemporal hypometabolism (3 of 5 were seizure-free), 1 had frontal hypometabolism, and 14 had no lateralized PET abnormality (4 of 7 were seizure-free). Patients who became seizure-free had significantly higher lateral temporal asymmetry index (AI). PET showed > or = 15% relative temporal hypometabolism (AI) in 12 of 22 patients with nonlateralized surface ictal VEEG and was capable of distinguishing between frontal and temporal foci in 16 of 24 patients with lateralized, but not localized, surface ictal video-EEG. CONCLUSIONS FDG-PET provides valuable data in patients with unlocalized surface ictal EEG and can reduce the number of patients who require IEEG studies. Quantitation is necessary for optimal PET interpretation.
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MESH Headings
- Brain/diagnostic imaging
- Brain/metabolism
- Deoxyglucose/analogs & derivatives
- Diagnosis, Differential
- Electrodes, Implanted
- Electroencephalography/methods
- Epilepsies, Partial/diagnosis
- Epilepsies, Partial/diagnostic imaging
- Epilepsies, Partial/surgery
- Epilepsy, Complex Partial/diagnosis
- Epilepsy, Complex Partial/diagnostic imaging
- Epilepsy, Complex Partial/surgery
- Fluorodeoxyglucose F18
- Functional Laterality
- Glucose/metabolism
- Humans
- Monitoring, Physiologic
- Telemetry
- Temporal Lobe/surgery
- Tomography, Emission-Computed
- Treatment Outcome
- Videotape Recording
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Affiliation(s)
- W H Theodore
- Clinical Epilepsy Section, NINDS NIH, Bethesda, Maryland 20892, USA
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34
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Abstract
Epilepsy research using positron emission tomography (PET) has provided considerable new information about ictal and interictal dysfunctions in human epilepsy. Neuroreceptor mapping with PET ligands has revealed altered central benzodiazepine receptor and opiate receptor densities in partial epilepsies interictally, and regional increases in endogenous opioid peptide concentrations during absence seizures. Imaging of perfusion and glucose metabolism during cognitive processing has shown interictal abnormalities of regional activation in partial and generalized epilepsies. The diagnostically robust patterns of interictal glucose hypometabolism are not adequately explained by macrostructural and microstructural alterations in temporal lobe epilepsy. Current investigations of the pathophysiology of interictal hypometabolism must address ultrastructural and neurochemical factors. Clinical PET in presurgical evaluation of medically refractory epilepsies remains an active area of research, but remarkably little antiepileptic drug research has exploited PET techniques.
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MESH Headings
- Anticonvulsants/pharmacokinetics
- Anticonvulsants/pharmacology
- Brain/diagnostic imaging
- Brain/metabolism
- Brain/physiopathology
- Cerebrovascular Circulation
- Deoxyglucose/analogs & derivatives
- Epilepsy/diagnostic imaging
- Epilepsy/metabolism
- Epilepsy/physiopathology
- Epilepsy, Temporal Lobe/diagnostic imaging
- Epilepsy, Temporal Lobe/metabolism
- Epilepsy, Temporal Lobe/physiopathology
- Flumazenil/metabolism
- Fluorodeoxyglucose F18
- Glucose/metabolism
- Humans
- Oxygen Radioisotopes/metabolism
- Receptors, GABA-A/metabolism
- Receptors, GABA-A/physiology
- Receptors, Muscarinic/metabolism
- Receptors, Muscarinic/physiology
- Receptors, Opioid/metabolism
- Receptors, Opioid/physiology
- Tomography, Emission-Computed
- Water
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Affiliation(s)
- T R Henry
- Department of Neurology, Entory University School of Medicine, Atlanta, Georgia, USA
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35
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Bidaut LM, Pascual-Marqui R, Delavelle J, Naimi A, Seeck M, Michel C, Slosman D, Ratib O, Ruefenacht D, Landis T, de Tribolet N, Scherrer JR, Terrier F. Three- to five-dimensional biomedical multisensor imaging for the assessment of neurological (dys) function. J Digit Imaging 1996; 9:185-98. [PMID: 8951098 DOI: 10.1007/bf03168617] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
This report describes techniques and protocols implemented at the Geneva Canton University Hospitals (HUG) for the combination of various biomedical imaging modalities and sensors including electromagnetic tomography, to study, assess, and localize neurological (dys) function. The interest for this combination stems from the broad variety of information brought out by (functional) magnetic resonance imaging, magnetic resonance spectroscopy, computed tomography, single-photon emission tomography, positron emission tomography, and electromagnetic tomography. Combining these data allows morphology, metabolism, and function to be studied simultaneously, the complementary nature of the information from these modalities becoming evident when studying pathologies reflected by metabolic or electrophysiologic dysfunctions. Compared with other current multimodality approaches, the one at the HUG is totally compatible with both clinical and research protocols, and efficiently addresses the multidimensional registration and visualization issues. It also smoothly integrates electrophysiology and related data as fully featured modalities.
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Affiliation(s)
- L M Bidaut
- Department of Medical Informatics, Geneva Canton University Hospital, Switzerland
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36
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Multimodal estimation of epileptic foci with dipole localization method and other technique. Brain Topogr 1996. [DOI: 10.1007/bf01191642] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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