RESUMEN
OBJECTIVE: Typical aging is associated with gradual cognitive decline and changes in brain structure. The observation that cognitive performance in mesial temporal lobe epilepsy (TLE) patients diverges from controls early in life with subsequent decline running in parallel would suggest an initial insult but does not support accelerated decline secondary to seizures. Whether TLE patients demonstrate similar trajectories of age-related gray (GM) and white matter (WM) changes as compared to healthy controls remains uncertain. METHODS: 3D T1-weighted and diffusion tensor images were acquired at a single site in 170 TLE patients (aged 23-74 years) with MRI signs of unilateral hippocampal sclerosis (HS, 77 right) and 111 healthy controls (aged 26-80 years). Global brain (GM, WM, total brain, and cerebrospinal fluid) and regional volumes (ipsi- and contralateral hippocampi), and fractional anisotropy (FA) of 10 tracts (three portions of corpus callosum, inferior longitudinal, inferior fronto-occipital and uncinate fasciculi, body of fornix, dorsal and parahippocampal-cingulum, and corticospinal tract) were compared between groups as a function of age. RESULTS: There were significant reductions of global brain and hippocampi volumes (greatest ipsilateral to HS), and FA of all 10 tracts in TLE versus controls. For TLE patients, regression lines run in parallel to those from controls for brain volumes and FA (for all tracts except the parahippocampal-cingulum and corticospinal tract) versus age across the adult lifespan. INTERPRETATION: These results imply a developmental hindrance occurring earlier in life (likely in childhood/neurodevelopmental stages) rather than accelerated atrophy/degeneration of most brain structures herein analyzed in patients with TLE.
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Epilepsia del Lóbulo Temporal , Sustancia Blanca , Adulto , Humanos , Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Sustancia Blanca/diagnóstico por imagen , Longevidad , Imagen de Difusión Tensora/métodos , Encéfalo/diagnóstico por imagenRESUMEN
SUMMARY: In patients with mesial temporal lobe epilepsy, high-frequency, low-amplitude electrical stimulation (ES) was applied during 3 weeks through contacts of intracranial electrodes that defined the epileptogenic zone. This subacute ES induced cessation of spontaneous seizures, decreased the number of EEG interictal spikes, caused a 10-fold increase in threshold to induce postdischarges, and showed a profound decrease in regional blood flow of the stimulated area in SPECT studies. Autoradiography analysis of surgical specimens from these patients demonstrated increased expression of benzodiazepine receptors and in gamma-aminobutyric acid content, particularly in the parahippocampal cortex. These observations provided evidence of a gamma-aminobutyric acid-mediated antiepileptic effect induced by ES. Several reports of long-term hippocampal ES through internalized neurostimulators have confirmed the antiepileptic effect on mesial temporal lobe-initiated seizures, with preservation of neuropsychological performance, in particular memory functions. The experience of the authors is that the response is optimal in patients without hippocampal sclerosis evidenced by MRI, whereas it is less significant and delayed in patients with hippocampal sclerosis. Other studies reported the best result stimulating through the contacts in the subiculum, the transition between the hippocampus and parahippocampal cortex, that usually escapes to the hippocampal sclerosis. Currently, the effect of ES directed at the subiculum and the parahippocampal cortex in patients with hippocampal sclerosis is under investigation.
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Epilepsia del Lóbulo Temporal , Electroencefalografía , Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Epilepsia del Lóbulo Temporal/patología , Epilepsia del Lóbulo Temporal/terapia , Hipocampo , Humanos , Imagen por Resonancia Magnética , Esclerosis/patología , Convulsiones/patología , Convulsiones/terapia , Lóbulo Temporal/diagnóstico por imagenRESUMEN
BACKGROUND AND PURPOSE: Temporal lobe epilepsy secondary to hippocampal sclerosis is related to epileptogenic networks rather than a focal epileptogenic source. Graph-theoretical gray and white matter networks may help to identify alterations within these epileptogenic networks. METHODS: Twenty-seven patients with hippocampal sclerosis and 14 controls underwent magnetic resonance imaging, including 3D-T1, fluid-attenuated inversion recovery, and diffusion tensor imaging. Subject-specific structural gray and white matter network properties (normalized path length, clustering, and small-worldness) were reconstructed. Group differences and differences between those with higher and lower seizure burden (<4 vs. ≥4 average monthly seizures in the last year) in network parameters were evaluated. Additionally, correlations between network properties and disease-related variables were calculated. RESULTS: All patients with hippocampal sclerosis as one group did not have altered gray or white matter network properties (all p > .05). Patients with lower seizure burden had significantly lower gray matter small-worldness and normalized clustering compared to controls and those with higher seizure burden (all p < .04). A higher number of monthly seizures was significantly associated with increased gray and white matter small-worldness, indicating a more rigid network. CONCLUSION: Overall, there were no differences in network properties in this group of patients with hippocampal sclerosis. However, patients with lower seizure burden had significantly lower gray matter network indices, indicating a more random organization. The correlation between higher monthly seizures and a more rigid network is driven by those with higher seizure burden, who presented a more rigid network compared to those with a lower seizure burden.
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Epilepsia del Lóbulo Temporal , Sustancia Blanca , Encéfalo , Imagen de Difusión Tensora , Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Hipocampo/diagnóstico por imagen , Hipocampo/patología , Humanos , Imagen por Resonancia Magnética , Esclerosis/patología , Convulsiones/diagnóstico por imagen , Convulsiones/patología , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patologíaRESUMEN
The default mode network (DMN) consists of the deactivation of specific regions during the performance of cognitive tasks and activation during resting or mind wandering. Several pieces of evidence indicate the impairment of DMN in patients with mesial temporal lobe epilepsy (MTLE). However, most of these studies combined different underlying etiologies, failing to disentangle the influence of seizures and presence and side of hippocampal sclerosis (HS). We included 119 patients with MTLE divided into right-HS (nâ¯=â¯42), left-HS (nâ¯=â¯46), and magnetic resonance imaging (MRI)-negative MTLE (nâ¯=â¯31) and controls (nâ¯=â¯59). All underwent resting-state seed-based functional connectivity (FC), with a seed placed at the posterior cingulate cortex (PCC), an essential node for the DMN. To access group inferences, we used an SPM (Statistical Parametric Mapping) full-factorial model to compare patterns of activation using pairwise comparisons among all groups. Our results indicate a different pattern of DMN FC when controlling for side and presence of HS. The group with right-HS had increased FC in the left angular gyrus and the left middle occipital gyrus, when compared to controls, and increased FC of the left hippocampus when compared to the group with left-HS. The MRI-negative group had increased FC of the left hippocampus, left ventral diencephalon, and left fusiform gyrus as compared to left-HS, but did not show any areas of reduced FC compared to controls. By contrast, the group with left-HS did not show areas of increased FC compared to controls or the right-HS and had reduced FC in the left hippocampus compared to controls. Hence, the right-HS presented increased FC in areas related to the DMN in the left hemisphere; the MRI-negative group also showed increased FC in left-sided structures close to temporal lobe when compared to left-HS, probably indicating engagement in a compensatory system. In a subanalysis considering only the MRI-negative with left-sided EEG (electroencephalogram) subgroup, we found differences against controls, with left angular gyrus more connected in the first group, but no significant differences when compared to the group with left-HS. We conclude that the origin of seizures on the left hemisphere seems to engender a less prominent capacity of recruiting other neighbor areas related to DMN as compared to right-HS and controls. Considering recent studies that have revealed the importance of DMN for cognitive skills and memory, our findings may indicate that deficiencies exhibited by patients with left-HS temporal lobe epilepsy (TLE) in connecting to the DMN could be a surrogate marker of their known worse neuropsychological performance. Further studies with direct comparisons between cognitive tests and FC within the DMN are needed to validate these findings, especially for MRI-negative patients. This article is part of the Special Issue "NEWroscience 2018".
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Epilepsia del Lóbulo Temporal , Mapeo Encefálico , Red en Modo Predeterminado , Epilepsia del Lóbulo Temporal/complicaciones , Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Epilepsia del Lóbulo Temporal/patología , Hipocampo/diagnóstico por imagen , Hipocampo/patología , Humanos , Imagen por Resonancia Magnética , Esclerosis/diagnóstico por imagen , Esclerosis/patología , Lóbulo TemporalRESUMEN
OBJECTIVE: Sudden unexpected death in epilepsy (SUDEP) is a tragic event. Cardiac models of sudden death state that, paradoxically, healthy individuals compose most of the victims of this event. Exploration of cardiac physiological variables related to outcome could help unveil risk markers for sudden death in epilepsy. We investigated left ventricle end-systolic elastance, arterial-effective elastance and ventricle-arterial coupling (VAC) in PWE compared with controls. MATERIAL & METHODS: Adult patients with temporal lobe epilepsy without known cardiovascular diseases were submitted to treadmill test and transthoracic echocardiogram. Individuals without epilepsy matched by sex, age, and body mass index composed the control group. Cardiac risk factors, exercise performance, autonomic data from treadmill test, systolic and diastolic function, morphological cardiac data, and left ventricle pressure-volume loop were recorded. RESULTS: Sixty subjects were consecutively enrolled (30 PWE and 30 controls). Epilepsy duration was 22.5 ± 10.7 years (age of onset 15.2 ± 10.1 years). Treadmill variables were significantly worse in TLE patients compared with controls. End-systolic elastance, arterial-effective elastance, and ventricle-arterial coupling were similar between groups. Female sex, percentage of maximal predicted heart rate achieved in exercise, exercise time, and epilepsy duration explained 28,4% of VAC in PWE in multiple stepwise linear regression (P = .018). CONCLUSIONS: Some aspects of the cardiac pressure-volume curves, mainly linked to left ventricle systolic performance, contractile function and their interaction with afterload appears normal in young PWE and cannot explain their increase risk to adverse outcomes or lower physical fitness.
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Enfermedades Cardiovasculares/fisiopatología , Epilepsia del Lóbulo Temporal/fisiopatología , Prueba de Esfuerzo/métodos , Función Ventricular Izquierda/fisiología , Adulto , Enfermedades Cardiovasculares/diagnóstico por imagen , Enfermedades Cardiovasculares/mortalidad , Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Epilepsia del Lóbulo Temporal/mortalidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Muerte Súbita e Inesperada en la Epilepsia/prevención & control , Adulto JovenRESUMEN
INTRODUCTION: Evidence has been provided that the subiculum may play an important role in the generation of seizures. Electrical stimulation at this target has been reported to have anticonvulsive effects in kindling and pilocarpine rat models, while in a clinical study of hippocampal deep brain stimulation (DBS), contacts closest to the subiculum were associated with a better anticonvulsive effect. OBJECTIVES: To evaluate the effect of electrical stimulation of the subiculum in patients with refractory mesial temporal lobe epilepsy (MTLE) who have hippocampal sclerosis (HS). METHODS: Six patients with refractory MTLE and HS, who had focal impaired awareness seizures (FIAS) and focal to bilateral tonic-clonic seizures (FBTCS), had DBS electrodes implanted in the subiculum. During the first month after implantation, all patients were OFF stimulation, then they all completed an open-label follow-up of 24 months ON stimulation. DBS parameters were set at 3 V, 450 µs, 130 Hz, cycling stimulation 1 min ON, 4 min OFF. RESULTS: There was a mean reduction of 49.16% (±SD 41.65) in total seizure number (FIAS + FBTCS) and a mean reduction of 67.93% (±SD 33.33) in FBTCS at 24 months. FBTCS decreased significantly with respect to baseline, starting from month 2 ON stimulation. CONCLUSIONS: Subiculum stimulation is effective for FBTCS reduction in patients with MTLE and HS, suggesting that the subiculum mediates the generalization rather than the genesis of mesial temporal lobe seizures. Better results are observed at longer follow-up times.
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Estimulación Encefálica Profunda/métodos , Epilepsia Refractaria/diagnóstico por imagen , Epilepsia Refractaria/terapia , Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Epilepsia del Lóbulo Temporal/terapia , Hipocampo/diagnóstico por imagen , Adolescente , Adulto , Animales , Femenino , Estudios de Seguimiento , Humanos , Masculino , Estudios Prospectivos , Ratas , Esclerosis , Resultado del Tratamiento , Adulto JovenRESUMEN
OBJECTIVE: To evaluate the interactions of metabolic neuronal-glial changes with the presence and hemispheric-side of hippocampal sclerosis (HS) and its potential role in predicting pharmacoresistance in temporal lobe epilepsy (TLE). METHODS: We included structural magnetic resonance imaging (MRI) and proton magnetic resonance spectroscopy (1 H-MRS) metabolic data for 91 patients with unilateral TLE and 50 healthy controls. We measured the values of total N-acetyl aspartate/total creatine (tNAA/tCr), glutamate/tCr (Glu/tCr), and myo-inositol/tCr (mIns/tCr). To assess the influence of the pharmacoresponse and hemispheric-side of HS on metabolic data, the relationship between clinical and MRI data, and the predictive value of NAA/Cr, we used analysis of variance/covariance and built a logistic regression model. We used bootstrap simulations to evaluate reproducibility. RESULTS: Bilateral tNAA/tCr reduction was associated with pharmacoresistance and with left HS, a decrease of Glu/tCr ipsilateral to the seizure focus was associated with pharmacoresistance, and ipsilateral mIns/tCr increase was related to pharmacoresistance and the presence of left HS. The logistic regression model containing clinical and 1 H-MRS data discriminated pharmacoresistance (area under the curve [AUC] = 0.78). However, the reduction of tNAA/tCr was the main predictor, with the odds 2.48 greater for pharmacoresistance. SIGNIFICANCE: Our study revealed a spectrum of neuronal-glial changes in TLE, which was associated with pharmacoresistance, being more severe in left-sided HS and less severe in MRI-negative TLE. These noninvasive, in vivo biomarkers provide valuable additional information about the interhemispheric differences in metabolic dysfunction, seizure burden, and HS, and may help to predict pharmacoresistance.
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Anticonvulsivantes/uso terapéutico , Epilepsia Refractaria/patología , Epilepsia del Lóbulo Temporal/tratamiento farmacológico , Hipocampo/patología , Neuroglía/patología , Neuronas/patología , Adulto , Biomarcadores , Estudios de Casos y Controles , Creatina/metabolismo , Epilepsia Refractaria/tratamiento farmacológico , Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Epilepsia del Lóbulo Temporal/metabolismo , Epilepsia del Lóbulo Temporal/patología , Femenino , Ácido Glutámico/metabolismo , Hipocampo/diagnóstico por imagen , Humanos , Inositol/metabolismo , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , N-Metilaspartato/metabolismo , Neuroimagen , Espectroscopía de Protones por Resonancia Magnética , Esclerosis , Resultado del Tratamiento , Adulto JovenRESUMEN
BACKGROUND: Positron emission tomography (PET) imaging in epilepsy is an in vivo technique that allows the localization of a possible seizure onset zone (SOZ) during the interictal period. Stereo-electro-encephalography (SEEG) is the gold standard to define the SOZ. The objective of this research was to evaluate the accuracy of PET imaging in localizing the site of SOZ compared with SEEG. METHODS: Seven patients with refractory temporal lobe epilepsy (Ep) and 2 healthy controls (HC) underwent 2 PET scans, one with 2-[18F]-fluoro-2-deoxy-D-glucose (FDG) and another with 2'-[18F]fluoroflumazenil (FFMZ), acquired 1 day apart. FDG was acquired for 10 min (static scan) 1 h after administration. An FFMZ scan was acquired for 60 min from radiopharmaceutical administration in a dynamic mode. Each brain PET image was segmented using a standard template implemented in PMOD 3.8. The pons was used as the reference region for modeling of the nondisplaceable binding potential (BPND)for FFMZ, and to obtain uptake ratios for FDG. SEEG studies of patients were performed as a part of their surgical evaluation to define the SOZ. RESULTS: Well-defined differences between HC and Ep were found with both radiopharmaceuticals, showing the utility to identify abnormal brain regions using quantitative PET imaging. Lateralization of the SOZ findings by PET (lower uptake/binding in a specific brain hemisphere) matched in 86% for FFMZ and 71% for FDG with SEEG data. CONCLUSION: Quantitative PET imaging is an excellent complementary tool that matches reasonably well with SEEG to define SOZ in presurgical evaluation.
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Epilepsia Refractaria/diagnóstico por imagen , Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Flumazenil/análogos & derivados , Radioisótopos de Flúor , Fluorodesoxiglucosa F18 , Tomografía de Emisión de Positrones/métodos , Adolescente , Adulto , Mapeo Encefálico/métodos , Epilepsia Refractaria/metabolismo , Epilepsia Refractaria/cirugía , Epilepsia del Lóbulo Temporal/metabolismo , Epilepsia del Lóbulo Temporal/cirugía , Femenino , Flumazenil/metabolismo , Radioisótopos de Flúor/metabolismo , Fluorodesoxiglucosa F18/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Convulsiones/diagnóstico por imagen , Convulsiones/metabolismo , Convulsiones/cirugíaRESUMEN
Autonomic dysfunction is linked to sudden death regardless of the presence of structural heart disease. The pathway from autonomic dysfunction to sudden death is not fully understood, but myocardial sympathetic stimulation leading to arrhythmia and/or cardiac fibrosis might play a role. Our goal was to evaluate cardiac stiffness by echocardiography and its association with clinical, structural, and autonomic variables in people with epilepsy (PWE) compared to healthy controls. A 12-lead electrocardiogram, treadmill testing, and transthoracic echocardiography from 30 patients with temporal lobe epilepsy (TLE) without any known cardiovascular disorders were compared to 30 individuals without epilepsy matched by sex, age, and body mass index. Distribution of cardiovascular risk factors was similar in both groups. PWE had a higher left ventricle stiffness, left ventricle filling pressure, and greater left atrial volume as well as markers of autonomic dysfunction such as impaired chronotropic index and percentage achieved of predicted peak heart rate at effort. In multiple regressions, autonomic dysfunction explained 52% of stiffness and carbamazepine treatment and polytherapy with antiepileptic drugs (AEDs) explained, additionally, 6% each. Stiffness is increased in young patients with TLE and is related to autonomic dysfunction and to a lesser extent, carbamazepine use and polytherapy with AEDs.
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Enfermedades del Sistema Nervioso Autónomo/etiología , Enfermedades Cardiovasculares/etiología , Epilepsia del Lóbulo Temporal/complicaciones , Adolescente , Adulto , Enfermedades del Sistema Nervioso Autónomo/diagnóstico por imagen , Enfermedades Cardiovasculares/diagnóstico por imagen , Niño , Electrocardiografía , Electroencefalografía , Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Prueba de Esfuerzo , Femenino , Humanos , Modelos Lineales , Imagen por Resonancia Magnética , Masculino , Estudios Retrospectivos , Adulto JovenRESUMEN
Status epilepticus (SE) can result in an overproduction of hydrogen peroxide (H2O2), which contributes to oxidative stress and brain injury during different phases of epileptogenesis and seizures. In this study, we measured the extracellular H2O2 concentration in the rat hippocampus in a temporal lobe epilepsy model. A new fluorescent technique for measuring H2O2 in vivo simultaneously with electroencephalography recording was tested. The method consists of mixing microdialysate with an enzymatic reactor to produce a fluorescent compound. The fluorescence intensity was measured every second and was proportional to the H2O2 concentration. The results showed that H2O2 was released during SE; we detected a significant increase of up to five times over the baseline value that correlated with changes in electrical activity. We also observed that H2O2 was produced for days after SE and was associated with continuous neuronal death and seizure generation. Therefore, we monitored H2O2 48 h and 15 days after SE, observing increases of up to 96 and 124%, respectively, accompanied by changes in electrical activity with spontaneous discharges of large amplitude. These changes may reflect the oxidative stress generated during epileptogenesis that remains during the chronic period (458% increased) with the presence of large spikes, indicating that the H2O2 could also participate in the generation and maintenance of spontaneous recurrent seizures. There are no previous reports on the detection of H2O2 at this temporal resolution; thus, this study contributes a novel technique for studying and understanding epileptogenesis to develop new antioxidant strategies for the treatment of temporal lobe epilepsy.
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Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Epilepsia del Lóbulo Temporal/metabolismo , Peróxido de Hidrógeno/metabolismo , Imagen Óptica/métodos , Estrés Oxidativo/fisiología , Animales , Modelos Animales de Enfermedad , Electroencefalografía/métodos , Masculino , Imagen Multimodal/métodos , Pilocarpina , Ratas Wistar , Estado Epiléptico/diagnóstico por imagen , Estado Epiléptico/metabolismoRESUMEN
BACKGROUND AND OBJECTIVE: The parahippocampal gyrus plays an important role in the epileptogenic pathways of mesial temporal lobe epilepsy caused by hippocampal sclerosis (mTLE-HS); its resection could prevent epileptic seizures with fewer complications. This study evaluates the initial efficacy and safety of anterior temporal lobectomy (ATL), selective amygdalohipppocampectomy (SAH), and parahippocampectomy (PHC) surgical approaches in mTLE-HS. METHODS: A randomized comparative pilot clinical trial (2008-2011) was performed that included patients with mTLE-HS who underwent ATL, trans-T3 SAH, and trans-T3 PHC. Their sociodemographic characteristics, visual field profiles, verbal and visual memory profiles, and Engel scale outcome at baseline and at 1 and 5 years are described, using descriptive statistics along with parametric and nonparametric tests. RESULTS: Forty-three patients with a mean age of 35.2 years (18-56 years), 65% female, were analyzed: 14 underwent PHC, 14 ATL, and 15 SAH. The following percentages refer to those patients who were seizure free (Engel class IA) at 1-year and 5-year follow-up, respectively: 42.9% PHC, 71.4% ATL, and 60% SAH (P = 0.304); 28.6% PHC, 50% ATL, and 53.3% SAH (P = 0.353). Postoperative visual field deficits were 0% PHC, 85.7% ATL, and 46.7% SAH (P = 0.001). Verbal and/or visual memory worsening were present in 21.3% PHC, 42.8% ATL, and 33.4% SAH (P = 0.488) and preoperative and postoperative visual memory scores were significantly different in the SAH group only (P = 0.046). CONCLUSIONS: PHC, ALT, and SAH show a preliminary similar efficacy in short-term seizure-free rates in patients with mTLE-HS. However, PHC efficacy in the long-term decreases compared with the other surgical techniques. PHC does not produce postoperative visual field deficits.
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Epilepsia del Lóbulo Temporal/etiología , Epilepsia del Lóbulo Temporal/cirugía , Hipocampo/patología , Procedimientos Neuroquirúrgicos/métodos , Giro Parahipocampal/cirugía , Esclerosis/complicaciones , Adolescente , Adulto , Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Femenino , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética , Masculino , Trastornos de la Memoria/etiología , Trastornos de la Memoria/cirugía , Persona de Mediana Edad , Giro Parahipocampal/fisiología , Proyectos Piloto , Esclerosis/patología , Estadísticas no Paramétricas , Resultado del Tratamiento , Aprendizaje Verbal/fisiología , Adulto JovenRESUMEN
In the diagnosis of mesial temporal sclerosis (MTS), sensitivity, specificity and predictive values of qualitative assessment using conventional magnetic resonance imaging are low, mainly in mild or bilateral atrophy. Quantitative analysis may improve this performance. We evaluated the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of quantitative analysis using the hippocampal volumetric index (HVI) and hippocampal asymmetry index (HAI) compared with qualitative assessment in the MTS diagnosis. Twenty-five patients diagnosed with MTS, and 25 healthy subjects underwent conventional magnetic resonance imaging. Hippocampal volumes were obtained using an automated software (FreeSurfer); HVI and HAI were calculated. Receiver operating characteristic curve analysis was performed to obtain the optimal threshold values. Sensitivity, specificity and predictive values were calculated. Sensitivity, specificity, PPV and NPV for qualitative analysis were 44.00%, 96.00%, 91.67% and 63.16%, respectively. In the quantitative analysis, a threshold value of K = 0.22 for HVI provided a sensitivity value of 76.00%, specificity value of 96.00%, PPV of 95.00% and NPV of 80.00%. A threshold value of K = 0.06 for HAI provided the minimum C1 and C2 errors, with a sensitivity value of 88.00%, specificity value of 100%, PPV of 100% and NPV of 89.30%. A statistically significant difference was observed for HAI ( P < 0.0001), and ipsilateral HVI (left MTS, P = 0.0152; right MTS, P < 0.0001), between MTS and healthy groups. The HVI and HAI, both individually and in conjunction, improved the sensitivity, specificity and predictive values of magnetic resonance imaging in the diagnosis of MTS compared to the qualitative analysis and other quantitative techniques. The HAI is highly accurate in the diagnosis of unilateral MTS, whereas the HVI may be better for bilateral MTS cases.
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Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Esclerosis , Adolescente , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Sensibilidad y EspecificidadRESUMEN
OBJECTIVE: To compare surgical outcome in mesial temporal lobe epilepsy (MTLE) patients with unilateral hippocampal sclerosis (MTLE-HS) who had or did not have preoperative video-electroencephalographic monitoring (VEEG). METHODS: A prospective study was undertaken with 166 consecutive pharmacoresistant unilateral MTLE-HS patients. All patients were investigated with detailed seizure semiology, serial routine outpatient EEG, magnetic resonance imaging, neuropsychological evaluation, and if necessary, other examinations. Postoperative follow-up ranged between 2 and 16 years. Patients were divided into: (1) patients operated on based on routine outpatient EEG information, with >80% of EEGs with unilateral interictal epileptiform discharges (IEDs) ipsilateral to HS or ictal events (n = 71); and (2) patients submitted to preoperative VEEG (n = 95). To avoid the bias generated by ictal recordings, we performed a subanalysis of: (1) patients without preoperatively ictal recordings (n = 80) and (2) patients with ictal recordings in VEEG or routine outpatient EEG (n = 86). RESULTS: Groups were similar regarding gender, age at surgery, seizure onset, preoperative seizure frequency, and duration of follow-up. Overall, 136/166 (81.92%) were classified as Engel I seizure outcome, with no difference between groups; 76.84% and 88.73% of patients with and without VEEG, respectively, had Engel I postoperative seizure outcome (P = .77). The time lag until surgery was shorter in the group without VEEG (80 vs 38 months; P = .01). Considering ictal recordings, 76.74% of patients with seizures recorded and 87.50% without ictal recordings had Engel I outcome (P = .11). SIGNIFICANCE: We performed the first prospective study in a tertiary epilepsy center comparing surgical outcomes in unilateral MTLE-HS patients investigated preoperatively with and without VEEG. Based on the surgical outcome, VEEG is not imperative in patients with unilateral MTLE-HS who have compatible semiology and clearly ipsilateralized IEDs evaluated by a multidisciplinary and experienced epilepsy group.
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Epilepsia Refractaria/cirugía , Electroencefalografía/métodos , Epilepsia del Lóbulo Temporal/cirugía , Hipocampo/patología , Hospitalización , Monitoreo Fisiológico/métodos , Cuidados Preoperatorios/métodos , Adolescente , Adulto , Anciano , Estudios de Casos y Controles , Epilepsia Refractaria/diagnóstico por imagen , Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Femenino , Estudios de Seguimiento , Hipocampo/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Procedimientos Neuroquirúrgicos , Estudios Prospectivos , Esclerosis , Grabación en Video , Adulto JovenRESUMEN
Objectives To assess depressive disorders in patients with mesial temporal lobe epilepsy (MTLE) refractory to medical treatment. Methods Adult patients with refractory MTLE completed two questionnaires (Mini International Neuropsychiatric Interview (MINI) and the Beck Depression Inventory (BDI) had a semi-structured psychiatric interview and a high resolution MRI scan. For complete neuropsychiatric diagnosis, as per International Classification of Diseases (ICD-10), the results were combined with clinical history and additional information from the patients' family. Results Of the 40 patients identified for this case series study which took place from 2008-2012, 31 (77.5%) had a depressive disorder: 14 had dysthymia, 11 had recurrent depressive disorder and 6 had bipolar disorder. Of the nine patients without a firm diagnosis of mood disorder, seven had isolated symptoms of depression or anxiety and two presented with mixed depression/anxiety symptoms. Only 8/31 (25.8%) patients were receiving antidepressant treatment. There was no association between BDI scores and seizure frequency. No significant difference was found between patients with and without depression and the presence or laterality of HA. Conclusions Depressive disorders are common, underdiagnosed and undertreated in patients with refractory MTLE.
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Anticonvulsivantes/uso terapéutico , Antidepresivos/uso terapéutico , Trastorno Depresivo/fisiopatología , Epilepsia Refractaria/fisiopatología , Epilepsia del Lóbulo Temporal/fisiopatología , Calidad de Vida/psicología , Adulto , Benzodiazepinas/uso terapéutico , Carbamazepina/uso terapéutico , Clobazam , Trastorno Depresivo/complicaciones , Trastorno Depresivo/diagnóstico por imagen , Trastorno Depresivo/tratamiento farmacológico , Epilepsia Refractaria/complicaciones , Epilepsia Refractaria/diagnóstico por imagen , Epilepsia Refractaria/tratamiento farmacológico , Epilepsia del Lóbulo Temporal/complicaciones , Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Epilepsia del Lóbulo Temporal/tratamiento farmacológico , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Neuroimagen , Escalas de Valoración Psiquiátrica , Encuestas y CuestionariosRESUMEN
Interictal hypometabolism is commonly measured by 18-fluoro-deoxyglucose Positron Emission Tomography (FDG-PET) in the temporal lobe of patients with mesial temporal lobe epilepsy (MTLE-HS). Left temporal lobe interictal FDG-PET hypometabolism has been associated with verbal memory impairment, while right temporal lobe FDG-PET hypometabolism is associated with nonverbal memory impairment. The biochemical mechanisms involved in these findings remain unknown. In comparison to healthy controls (n=21), surgically treated patients with MTLE-HS (n=32, left side=17) had significant lower scores in the Rey Auditory Verbal Learning Test (RAVLT retention and delayed), Logical Memory II (LMII), Boston Naming test (BNT), Letter Fluency and Category Fluency. We investigated whether enzymatic activities of the mitochondrial enzymes Complex I (C I), Complex II (C II), Complex IV (C IV) and Succinate Dehydrogenase (SDH) from the resected samples of the middle temporal neocortex (mTCx), amygdala (AMY) and hippocampus (HIP) were associated with performance in the RAVLT, LMII, BNT and fluency tests of our patients. After controlling for the side of hippocampus sclerosis, years of education, disease duration, antiepileptic treatment and seizure outcome after surgery, no independent associations were observed between the cognitive test scores and the analyzed mitochondrial enzymatic activities (p>0.37). Results indicate that memory and language impairment observed in MTLE-HS patients are not strongly associated with the levels of mitochondrial CI, CII, SDH and C IV enzymatic activities in the temporal lobe structures ipsilateral to the HS lesion.
Asunto(s)
Encéfalo/metabolismo , Epilepsia del Lóbulo Temporal/complicaciones , Epilepsia del Lóbulo Temporal/patología , Trastornos de la Memoria/etiología , Complejos Multienzimáticos/metabolismo , Adulto , Anticonvulsivantes/uso terapéutico , Encéfalo/diagnóstico por imagen , Epilepsia Refractaria/complicaciones , Epilepsia Refractaria/diagnóstico por imagen , Epilepsia Refractaria/patología , Electroencefalografía , Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Epilepsia del Lóbulo Temporal/tratamiento farmacológico , Femenino , Fluorodesoxiglucosa F18 , Humanos , Masculino , Trastornos de la Memoria/diagnóstico por imagen , Pruebas Neuropsicológicas , Tomografía de Emisión de Positrones , Estadísticas no ParamétricasRESUMEN
BACKGROUND: Although anterior temporal lobectomy may be a definitive surgical treatment for epileptic patients with mesial temporal sclerosis, it often results in verbal, visual, and cognitive dysfunction. Studies have consistently reported the advantages of selective procedures compared with a standard anterior temporal lobectomy, mainly in terms of neuropsychological outcomes. OBJECTIVE: To describe a new technique to perform a selective amygdalohippocampectomy (SAH) through a transpalpebral approach with endoscopic assistance. METHODS: A mini fronto-orbitozygomatic craniotomy through an eyelid incision was performed in 8 patients. Both a microscope and neuroendoscope were used in the surgeries. An anterior SAH was performed in 5 patients who had the diagnosis of temporal lobe epilepsy with mesial temporal sclerosis. One patient had a mesial temporal lesion suggesting a ganglioglioma. Two patients presented mesial temporal cavernomas with seizures originating from the temporal lobe. RESULTS: The anterior approach allowed removal of the amygdala and hippocampus. The image-guided system and postoperative evaluation confirmed that the amygdala may be accessed and completely removed through this route. The hippocampus was partially resected. All patients have discontinued medication with no more epileptic seizures. The patients with cavernomas and ganglioglioma also had their lesions completely removed. One-year follow-up has shown no visible scars. CONCLUSION: The anterior route for SAH is a rational and direct approach to the mesial temporal lobe. Anterior SAH is a safe, less invasive procedure that provides early identification of critical vascular and neural structures in the basal cisterns. The transpalpebral approach provides a satisfactory cosmetic outcome.
Asunto(s)
Amígdala del Cerebelo/cirugía , Conjuntiva/cirugía , Endoscopía/métodos , Hipocampo/cirugía , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Adulto , Anciano , Amígdala del Cerebelo/diagnóstico por imagen , Neoplasias Encefálicas/complicaciones , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/cirugía , Trastornos del Conocimiento/etiología , Trastornos del Conocimiento/cirugía , Conjuntiva/diagnóstico por imagen , Craneotomía/métodos , Electroencefalografía , Epilepsia del Lóbulo Temporal/complicaciones , Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Epilepsia del Lóbulo Temporal/cirugía , Femenino , Lóbulo Frontal/cirugía , Hemangioma Cavernoso/complicaciones , Hemangioma Cavernoso/diagnóstico por imagen , Hemangioma Cavernoso/cirugía , Hipocampo/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
BACKGROUND: Surgical access to the temporal horn is necessary to treat tumors and vascular lesions, but is used mainly in patients with mediobasal temporal epilepsy. The surgical approaches to this cavity fall into 3 primary categories: lateral, inferior, and transsylvian. The current neurosurgical literature has underestimated the interruption of involved fiber bundles and the correlated clinical manifestations. OBJECTIVE: To delineate the interruption of fiber bundles during the different approaches to the temporal horn. METHODS: We simulated the lateral (trans-middle temporal gyrus), inferior (transparahippocampal gyrus), and transsylvian approaches in 20 previously frozen, formalin-fixed human brains (40 hemispheres). Fiber dissection was then done along the lateral and inferior aspects under the operating microscope. Each stage of dissection and its respective fiber tract interruption were defined. RESULTS: The lateral (trans-middle temporal gyrus) approach interrupted "U" fibers, the superior longitudinal fasciculus (inferior arm), occipitofrontal fasciculus (ventral segment), uncinate fasciculus (dorsolateral segment), anterior commissure (posterior segment), temporopontine, inferior thalamic peduncle (posterior fibers), posterior thalamic peduncle (anterior portion), and tapetum fibers. The inferior (transparahippocampal gyrus) approach interrupted "U" fibers, the cingulum (inferior arm), and fimbria, and transected the hippocampal formation. The transsylvian approach interrupted "U" fibers (anterobasal region of the extreme capsule), the uncinate fasciculus (ventromedial segment), and anterior commissure (anterior segment), and transected the anterosuperior aspect of the amygdala. CONCLUSION: White matter dissection improves our knowledge of the complex anatomy surrounding the temporal horn. Identifying the fiber bundles at risk during each surgical approach adds important information for choosing the appropriate surgical strategy.
Asunto(s)
Cuerpo Calloso/cirugía , Epilepsia del Lóbulo Temporal/patología , Lóbulo Temporal/cirugía , Sustancia Blanca/patología , Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Epilepsia del Lóbulo Temporal/cirugía , Femenino , Humanos , Masculino , Fibras Nerviosas Mielínicas/patologíaRESUMEN
OBJECTIVE: We designed a prospective, randomized, controlled, double-blind study to evaluate the efficacy of hippocampal deep brain stimulation (Hip-DBS) in patients with refractory temporary lobe epilepsy (TLE). METHODS: Sixteen adult patients with refractory TLE were studied. Patient's workup included medical history, interictal and ictal electroencephalography (EEG), and high-resolution 1.5T magnetic resonance imaging (MRI). Patients were randomized on a 1:1 proportion to an active (stimulation on) or to a control (no stimulation) arm. After implantation, patients were allowed to recover for 1 month, which was followed by a 1-month titration (or sham) period. The 6-month blinded phase started immediately afterward. A postoperative MRI confirmed the electrode's position in all patients. All patients received bipolar continuous stimulation. Stimulus duration was 300 µs and frequency was 130 Hz; final intensity was 2 V. Patients were considered responders when they had at least 50% seizure frequency reduction. RESULTS: All patients had focal impaired awareness seizures (FIAS, complex partial seizures), and 87% had focal aware seizures (FAS, simple partial seizures). Mean preoperative seizure frequency was 12.5 ± 9.4 (mean ± standard deviation) per month. MRI findings were normal in two patients, disclosed bilateral mesial temporal sclerosis (MTS) in three, left MTS in five, and right MTS in six patients. An insertional effect could be noted in both control and active patients. In the active group (n = 8), four patients became seizure-free; seven of eight were considered responders and one was a nonresponder. There was a significant difference regarding FIAS frequency between the two groups from the first month of full stimulation (p < 0.001) until the end of the blinded phase (p < 0.001). This was also true for FAS, except for the third month of the blinded phase. SIGNIFICANCE: Hip-DBS was effective in significantly reducing seizure frequency in patients with refractory TLE in the active group, as compared to the control group. Fifty-percent of the patients in the active group became seizure-free. The present study is the larger prospective, controlled, double-blind study to evaluate the effects of Hip-DBS published to date.
Asunto(s)
Estimulación Encefálica Profunda/métodos , Epilepsia Refractaria/terapia , Epilepsia del Lóbulo Temporal/terapia , Hipocampo , Adolescente , Adulto , Método Doble Ciego , Epilepsia Refractaria/diagnóstico por imagen , Electroencefalografía , Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Resultado del Tratamiento , Adulto JovenRESUMEN
RATIONALE: Benign Epilepsy of Childhood with Centrotemporal Spikes (BECTS) and temporal lobe epilepsy (TLE) represent two distinct models of focal epilepsy of childhood. In both, there is evidence of executive dysfunction. The purpose of the present study was to identify particular deficits in the executive function that would distinguish children with BECTS from children with TLE. METHODS: We prospectively evaluated 19 consecutive children and adolescents with TLE with hippocampal sclerosis (HS) (57.9% male; mean 11.74years [SD 2.05]; mean IQ 95.21 [SD 15.09]), 19 with BECTS (36.8% male; mean 10.95years [SD 2.33]; mean IQ 107.40 [SD 16.01]), and 21 age and gender-matched controls (33.3% male; mean 11.86years [SD 2.25]; mean IQ 108.67 [15.05]). All participants underwent a neuropsychological assessment with a comprehensive battery for executive and attentional functions. We used ANOVA and chi-square to evaluate differences on demographic aspects among groups (BECTS, TLE-HS, and control groups). Group comparisons on continuous variables were complemented by MANOVA and Bonferroni posthoc comparisons. RESULTS: Patients with BECTS had worse performance than controls in: Matching Familiar Figures Test, time (p=0.001); Matching Familiar Figures Test, time×errors index (p<0.001); Verbal Fluency for foods (p=0.038); Trail Making Test, part B time (p=0.030); Trail Making Test, part B number of errors (p=0.030); and WCST, number of categories achieved (p=0.043). Patients with BECTS had worse performance than patients with TLE-HS on Matching Familiar Figures Test, time (p=0.004), and Matching Familiar Figures Test, time×errors index (p<0.001). Patients with TLE-HS had worse performance than controls on the following tests: Verbal Fluency for foods (p=0.004); Wisconsin Card Sorting Test, the number of categories achieved (p<0.001); and Wisconsin Card Sorting Test, the number of perseverative errors (p=0.028). Patients with TLE-HS had worse performance than patients with BECTS on Digit Backward (p=0.002); and the Wisconsin Card Sorting Test, the number of perseverative errors (p<0.001). CONCLUSIONS: Patients with TLE and BECTS present distinct cognitive profiles. Patients with TLE-HS had worse performance in mental flexibility, concept formation, and working memory compared to BECTS. Patients with BECTS had worse inhibitory control compared to children with TLE-HS. Both TLE-HS and BECTS had a higher number of errors on an inhibitory control test. However, patients with BECTS had a slower mental processing even when compared to patients with TLE-HS. Rehabilitation programs for children with epilepsy must include children with benign epilepsies and must take into account the epileptic syndrome and its particular neurocognitive phenotype.
Asunto(s)
Potenciales de Acción/fisiología , Epilepsia Rolándica/diagnóstico por imagen , Epilepsia Rolándica/psicología , Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Epilepsia del Lóbulo Temporal/psicología , Función Ejecutiva/fisiología , Adolescente , Niño , Formación de Concepto/fisiología , Epilepsia Rolándica/fisiopatología , Epilepsia del Lóbulo Temporal/fisiopatología , Femenino , Humanos , Masculino , Memoria a Corto Plazo/fisiología , Trastornos Mentales/diagnóstico por imagen , Trastornos Mentales/fisiopatología , Trastornos Mentales/psicología , Pruebas Neuropsicológicas , Estudios Prospectivos , Prueba de Secuencia AlfanuméricaRESUMEN
BACKGROUND AND PURPOSE: MR-guided laser interstitial thermal therapy (MRgLITT) is an increasingly popular neuroablative method for the surgical treatment of epilepsy patients. This article intends to demonstrate the utility and pitfalls of imaging in the context of patient care with MRgLITT. MATERIAL AND METHODS: A retrospective review of the medical records and imaging database with six illustrative cases selected to demonstrate the use of imaging throughout patient management with MRgLITT in diverse clinical situations and pathologies. A review of the knowledge in the literature was applied to the relevant points discussed. RESULTS: Imaging findings were described in the setting of laser therapy in nonlesional epilepsy, mesial temporal sclerosis, dual pathology, periventricular nodular heterotopia, and schizencephaly. Discussion of imaging principles, potential pitfalls, as well as its use in the patient work-up and follow-up, is shown. CONCLUSIONS: MRgLITT is an alternative minimally invasive therapy for refractory epilepsy, which is becoming widely sought for. Imaging plays a crucial role prior to, during, and after the procedure.