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1.
Neuroimage ; 270: 119954, 2023 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-36828156

RESUMEN

We built normative brain atlases that animate millisecond-scale intra- and inter-hemispheric white matter-level connectivity dynamics supporting object recognition and speech production. We quantified electrocorticographic modulations during three naming tasks using event-related high-gamma activity from 1,114 nonepileptogenic intracranial electrodes (i.e., non-lesional areas unaffected by epileptiform discharges). Using this electrocorticography data, we visualized functional connectivity modulations defined as significant naming-related high-gamma modulations occurring simultaneously at two sites connected by direct white matter streamlines on diffusion-weighted imaging tractography. Immediately after stimulus onset, intra- and inter-hemispheric functional connectivity enhancements were confined mainly across modality-specific perceptual regions. During response preparation, left intra-hemispheric connectivity enhancements propagated in a posterior-to-anterior direction, involving the left precentral and prefrontal areas. After overt response onset, inter- and intra-hemispheric connectivity enhancements mainly encompassed precentral, postcentral, and superior-temporal (STG) gyri. We found task-specific connectivity enhancements during response preparation as follows. Picture naming enhanced activity along the left arcuate fasciculus between the inferior-temporal and precentral/posterior inferior-frontal (pIFG) gyri. Nonspeech environmental sound naming augmented functional connectivity via the left inferior longitudinal and fronto-occipital fasciculi between the medial-occipital and STG/pIFG. Auditory descriptive naming task enhanced usage of the left frontal U-fibers, involving the middle-frontal gyrus. Taken together, the commonly observed network enhancements include inter-hemispheric connectivity optimizing perceptual processing exerted in each hemisphere, left intra-hemispheric connectivity supporting semantic and lexical processing, and inter-hemispheric connectivity for symmetric oral movements during overt speech. Our atlases improve the currently available models of object recognition and speech production by adding neural dynamics via direct intra- and inter-hemispheric white matter tracts.


Asunto(s)
Lenguaje , Habla , Humanos , Habla/fisiología , Mapeo Encefálico/métodos , Encéfalo , Percepción Visual/fisiología
2.
Brain ; 145(2): 517-530, 2022 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-35313351

RESUMEN

This prospective study determined the use of intracranially recorded spectral responses during naming tasks in predicting neuropsychological performance following epilepsy surgery. We recruited 65 patients with drug-resistant focal epilepsy who underwent preoperative neuropsychological assessment and intracranial EEG recording. The Clinical Evaluation of Language Fundamentals evaluated the baseline and postoperative language function. During extra-operative intracranial EEG recording, we assigned patients to undergo auditory and picture naming tasks. Time-frequency analysis determined the spatiotemporal characteristics of naming-related amplitude modulations, including high gamma augmentation at 70-110 Hz. We surgically removed the presumed epileptogenic zone based on the intracranial EEG and MRI abnormalities while maximally preserving the eloquent areas defined by electrical stimulation mapping. The multivariate regression model incorporating auditory naming-related high gamma augmentation predicted the postoperative changes in Core Language Score with r2 of 0.37 and in Expressive Language Index with r2 of 0.32. Independently of the effects of epilepsy and neuroimaging profiles, higher high gamma augmentation at the resected language-dominant hemispheric area predicted a more severe postoperative decline in Core Language Score and Expressive Language Index. Conversely, the model incorporating picture naming-related high gamma augmentation predicted the change in Receptive Language Index with an r2 of 0.50. Higher high gamma augmentation independently predicted a more severe postoperative decline in Receptive Language Index. Ancillary regression analysis indicated that naming-related low gamma augmentation and alpha/beta attenuation likewise independently predicted a more severe Core Language Score decline. The machine learning-based prediction model suggested that naming-related high gamma augmentation, among all spectral responses used as predictors, most strongly contributed to the improved prediction of patients showing a >5-point Core Language Score decline (reflecting the lower 25th percentile among patients). We generated the model-based atlas visualizing sites, which, if resected, would lead to such a language decline. With a 5-fold cross-validation procedure, the auditory naming-based model predicted patients who had such a postoperative language decline with an accuracy of 0.80. The model indicated that virtual resection of an electrical stimulation mapping-defined language site would have increased the relative risk of the Core Language Score decline by 5.28 (95% confidence interval: 3.47-8.02). Especially, that of an electrical stimulation mapping-defined receptive language site would have maximized it to 15.90 (95% confidence interval: 9.59-26.33). In summary, naming-related spectral responses predict neuropsychological outcomes after epilepsy surgery. We have provided our prediction model as an open-source material, which will indicate the postoperative language function of future patients and facilitate external validation at tertiary epilepsy centres.


Asunto(s)
Epilepsia Refractaria , Epilepsia , Complicaciones Cognitivas Postoperatorias , Mapeo Encefálico/métodos , Epilepsia Refractaria/cirugía , Electrocorticografía/métodos , Epilepsia/cirugía , Humanos , Estudios Prospectivos
3.
J Pediatr Hematol Oncol ; 45(3): e406-e409, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36044309

RESUMEN

DICER1 syndrome is a rare inherited tumor predisposition syndrome associated with an increased risk for several malignant and benign tumors. We present a patient with pineal parenchymal tumor of intermediate differentiation who was found to have a germline pathogenic variant in DICER1 gene. Pineoblastoma is a known DICER1-related tumor; however, the association between pineal parenchymal tumor of intermediate differentiation and DICER1 mutation is rare with only 1 recent large molecular study that has reported this association. This report adds to the evolving tumor spectrum of DICER1 and highlights the importance of molecular evaluation of pediatric brain tumors, for both therapeutic decisions and long-term surveillance.


Asunto(s)
Neoplasias Encefálicas , Cuerpo Ciliar , ARN Helicasas DEAD-box , Predisposición Genética a la Enfermedad , Glándula Pineal , Pinealoma , Ribonucleasa III , Neoplasias de la Úvea , Humanos , Pinealoma/diagnóstico por imagen , Pinealoma/genética , Pinealoma/patología , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Glándula Pineal/diagnóstico por imagen , Glándula Pineal/patología , Ribonucleasa III/genética , ARN Helicasas DEAD-box/genética , Femenino , Adolescente , Síndrome , Cuerpo Ciliar/patología , Neoplasias de la Úvea/genética , Neoplasias de la Úvea/patología , Linaje
4.
Neuroimage ; 254: 119126, 2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-35331870

RESUMEN

OBJECTIVE: Our daily activities require frequent switches among competing responses at the millisecond time scale. We determined the spatiotemporal characteristics and functional significance of rapid, large-scale brain network dynamics during task switching. METHODS: This cross-sectional study investigated patients with drug-resistant focal epilepsy who played a Lumosity cognitive flexibility training game during intracranial electroencephalography (iEEG) recording. According to a given task rule, unpredictably switching across trials, participants had to swipe the screen in the direction the stimulus was pointing or moving. Using this data, we described the spatiotemporal characteristics of iEEG high-gamma augmentation occurring more intensely during switch than repeat trials, unattributable to the effect of task rule (pointing or moving), within-stimulus congruence (the direction of stimulus pointing and moving was same or different in a given trial), or accuracy of an immediately preceding response. Diffusion-weighted imaging (DWI) tractography determined whether distant cortical regions showing enhanced activation during task switch trials were directly connected by white matter tracts. Trial-by-trial iEEG analysis deduced whether the intensity of task switch-related high-gamma augmentation was altered through practice and whether high-gamma amplitude predicted the accuracy of an upcoming response among switch trials. RESULTS: The average number of completed trials during five-minute gameplay was 221.4 per patient (range: 171-285). Task switch trials increased the response times, whereas later trials reduced them. Analysis of iEEG signals sampled from 860 brain sites effectively elucidated the distinct spatiotemporal characteristics of task switch, task rule, and post-error-specific high-gamma modulations. Post-cue, task switch-related high-gamma augmentation was initiated in the right calcarine cortex after 260 ms, right precuneus after 330 ms, right entorhinal after 420 ms, and bilateral anterior middle-frontal gyri after 450 ms. DWI tractography successfully showed the presence of direct white matter tracts connecting the right visual areas to the precuneus and anterior middle-frontal regions but not between the right precuneus and anterior middle-frontal regions. Task-related high-gamma amplitudes in later trials were reduced in the calcarine, entorhinal and anterior middle-frontal regions, but increased in the precuneus. Functionally, enhanced post-cue precuneus high-gamma augmentation improved the accuracy of subsequent responses among switch trials. CONCLUSIONS: Our multimodal analysis uncovered two temporally and functionally distinct network dynamics supporting task switching. High-gamma augmentation in the visual-precuneus pathway may reflect the neural process facilitating an attentional shift to a given updated task rule. High-gamma activity in the visual-dorsolateral prefrontal pathway, rapidly reduced through practice, may reflect the cost of executing appropriate stimulus-response translation.


Asunto(s)
Encéfalo , Epilepsia Refractaria , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Mapeo Encefálico/métodos , Estudios Transversales , Electrocorticografía/métodos , Electroencefalografía/métodos , Humanos , Tiempo de Reacción/fisiología
5.
Brain ; 144(11): 3340-3354, 2021 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-34849596

RESUMEN

During a verbal conversation, our brain moves through a series of complex linguistic processing stages: sound decoding, semantic comprehension, retrieval of semantically coherent words, and overt production of speech outputs. Each process is thought to be supported by a network consisting of local and long-range connections bridging between major cortical areas. Both temporal and extratemporal lobe regions have functional compartments responsible for distinct language domains, including the perception and production of phonological and semantic components. This study provides quantitative evidence of how directly connected inter-lobar neocortical networks support distinct stages of linguistic processing across brain development. Novel six-dimensional tractography was used to intuitively visualize the strength and temporal dynamics of direct inter-lobar effective connectivity between cortical areas activated during each linguistic processing stage. We analysed 3401 non-epileptic intracranial electrode sites from 37 children with focal epilepsy (aged 5-20 years) who underwent extra-operative electrocorticography recording. Principal component analysis of auditory naming-related high-gamma modulations determined the relative involvement of each cortical area during each linguistic processing stage. To quantify direct effective connectivity, we delivered single-pulse electrical stimulation to 488 temporal and 1581 extratemporal lobe sites and measured the early cortico-cortical spectral responses at distant electrodes. Mixed model analyses determined the effects of naming-related high-gamma co-augmentation between connecting regions, age, and cerebral hemisphere on the strength of effective connectivity independent of epilepsy-related factors. Direct effective connectivity was strongest between extratemporal and temporal lobe site pairs, which were simultaneously activated between sentence offset and verbal response onset (i.e. response preparation period); this connectivity was approximately twice more robust than that with temporal lobe sites activated during stimulus listening or overt response. Conversely, extratemporal lobe sites activated during overt response were equally connected with temporal lobe language sites. Older age was associated with increased strength of inter-lobar effective connectivity especially between those activated during response preparation. The arcuate fasciculus supported approximately two-thirds of the direct effective connectivity pathways from temporal to extratemporal auditory language-related areas but only up to half of those in the opposite direction. The uncinate fasciculus consisted of <2% of those in the temporal-to-extratemporal direction and up to 6% of those in the opposite direction. We, for the first time, provided an atlas which quantifies and animates the strength, dynamics, and direction specificity of inter-lobar neural communications between language areas via the white matter pathways. Language-related effective connectivity may be strengthened in an age-dependent manner even after the age of 5.


Asunto(s)
Corteza Cerebral/anatomía & histología , Corteza Cerebral/fisiología , Conectoma/métodos , Lenguaje , Vías Nerviosas/anatomía & histología , Vías Nerviosas/fisiología , Adolescente , Atlas como Asunto , Niño , Preescolar , Imagen de Difusión Tensora/métodos , Electrocorticografía , Femenino , Humanos , Masculino , Modelos Neurológicos , Adulto Joven
6.
J Pediatr Hematol Oncol ; 44(2): e576-e579, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33930008

RESUMEN

Posterior fossa ependymomas A confer the worst prognosis among all subtypes. They demonstrate distinct epigenetic changes, which can be targeted with epigenetic modifiers like histone deacetylase inhibitors (Vorinostat). We describe a 3-year-old male diagnosed with a posterior fossa ependymoma who had a number of recurrences requiring multimodal therapy. Molecular analysis demonstrated a BCL-6 corepressor mutation, and methylation profiling matched with posterior fossa ependymomas A. He received craniospinal irradiation and focal boost with Vorinostat. Serial imaging after irradiation revealed a progressively decreasing tumor burden with nearly complete resolution of disease at 15 months. Histone deacetylase inhibitors demonstrate promise in treatment of carefully selected cases of ependymoma.


Asunto(s)
Ependimoma , Inhibidores de Histona Desacetilasas , Preescolar , Terapia Combinada , Ependimoma/genética , Ependimoma/patología , Ependimoma/terapia , Humanos , Masculino , Vorinostat/uso terapéutico
7.
Comput Electr Eng ; 101: 107948, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35495094

RESUMEN

The COVID-19 outbreak has led to a substantial loss of human life throughout the world and has a tremendous impact on healthcare services. Industry 4.0 technologies have established effective supply chain management towards the fulfillment of customized demands in the healthcare field. In addition, the internet of things, artificial intelligence, big data analytics, and 3D printing have been extensively used to combat the COVID-19 pandemic and assist in providing value-added services in the healthcare sector. Henceforth, this paper presents a scientometric analysis on the literature of aforementioned Industry 4.0 technologies in the context of COVID-19. It provides extensive insights into co-citation and co-occurrence analysis of high cited publications, participating countries, influential authors, prolific journals, and keywords using the CiteSpace tool. The analyses reveal that China has produced the highest research outputs, although India is the most collaborative country in this field. The current research hotspots include supply chain, 4D printing, and social distancing technologies. Furthermore, it explores emerging trends, intellectual structure of publications, research frontiers, and potential research directions for further work in the Industry 4.0 assisted healthcare domain.

8.
Epilepsia ; 62(10): 2372-2384, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34324194

RESUMEN

OBJECTIVE: This study was undertaken to build and validate a novel dynamic tractography-based model for localizing interictal spike sources and visualizing monosynaptic spike propagations through the white matter. METHODS: This cross-sectional study investigated 1900 spike events recorded in 19 patients with drug-resistant temporal lobe epilepsy (TLE) who underwent extraoperative intracranial electroencephalography (iEEG) and resective surgery. Twelve patients had mesial TLE (mTLE) without a magnetic resonance imaging-visible mass lesion. The remaining seven had a mass lesion in the temporal lobe neocortex. We identified the leading and lagging sites, defined as those initially and subsequently (but within ≤50 ms) showing spike-related augmentation of broadband iEEG activity. In each patient, we estimated the sources of 100 spike discharges using the latencies at given electrode sites and diffusion-weighted imaging-based streamline length measures. We determined whether the spatial relationship between the estimated spike sources and resection was associated with postoperative seizure outcomes. We generated videos presenting the spatiotemporal change of spike-related fiber activation sites by estimating the propagation velocity using the streamline length and spike latency measures. RESULTS: The spike propagation velocity from the source was 1.03 mm/ms on average (95% confidence interval = .91-1.15) across 133 tracts noted in the 19 patients. The estimated spike sources in mTLE patients with International League Against Epilepsy Class 1 outcome were more likely to be in the resected area (83.9% vs. 72.3%, φ = .137, p < .001) and in the medial temporal lobe region (80.5% vs. 72.5%, φ = .090, p = .002) than those associated with the Class ≥2 outcomes. The resulting video successfully animated spike propagations, which were confined within the temporal lobe in mTLE but involved extratemporal lobe areas in lesional TLE. SIGNIFICANCE: We have, for the first time, provided dynamic tractography visualizing the spatiotemporal profiles of rapid propagations of interictal spikes through the white matter. Dynamic tractography has the potential to serve as a unique epilepsy biomarker.


Asunto(s)
Epilepsia Refractaria , Epilepsia del Lóbulo Temporal , Epilepsia , Estudios Transversales , Epilepsia Refractaria/diagnóstico por imagen , Epilepsia Refractaria/cirugía , Electrocorticografía/métodos , Electroencefalografía/métodos , Epilepsia/diagnóstico por imagen , Epilepsia/cirugía , Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Epilepsia del Lóbulo Temporal/cirugía , Humanos
9.
Epilepsy Behav ; 124: 108363, 2021 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-34717248

RESUMEN

This retrospective cohort study investigated 53 patients with drug-resistant focal epilepsy and identified factors predictive of long-term satisfaction of patients and families following extraoperative intracranial EEG (iEEG) recording. The mixed model analysis assessed the utility of intracranial EEG (iEEG) predictor variables, including the seizure-onset zone (SOZ), modulation index (MI), and naming-related high-gamma activity. Modulation index, quantifying the coupling between high-frequency activity at >80 Hz and local slow wave at 3-4 Hz, effectively functions as a surrogate marker of the burden of interictal spike-and-slow-wave discharges. The mixed model specifically incorporated 'subtraction-MI', defined as the subtraction of mean z-score normalized MI across all preserved sites from that across all resected sites. Auditory naming-related high-gamma activity at 70-110 Hz is a biomarker to characterize the underlying language and speech function. The model incorporated 'maximum resected high-gamma', defined as the high-gamma percent change largest among sites included in the resected language-dominant hemispheric region. The model also incorporated the clinical and imaging profiles of given patients. The analysis revealed that complete removal of SOZ (p = 0.003) and younger patient age (p = 0.040) were independently associated with greater satisfaction. Neither 'subtraction-MI' nor 'maximum naming-related high-gamma' showed a significant and independent association with long-term satisfaction in our patient cohort. The observed impact of complete resection of SOZ and early surgery can be considered when counseling candidates for epilepsy surgery.

10.
Comput Commun ; 178: 297-306, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34518711

RESUMEN

In the current scenario of the COVID-19 pandemic and worldwide health emergency, one of the major challenges is to identify and predict the panic health of persons. The management of panic health and on-time evacuation prevents COVID-19 infection incidences in educational institutions and public places. Therefore, a system is required to predict the infection and suggests a safe evacuation path to people that control panic scenarios with mortality. In this paper, a fog-assisted cyber physical system is introduced to control panic attacks and COVID-19 infection risk in public places. The proposed model uses the concept of physical and cyber space. The physical space helps in real time data collection and transmission of the alert generation to the stakeholders. Cyberspace consists of two spaces, fog space, and cloud-space. The fog-space facilitates panic health and COVID-19 symptoms determination with alert generation for risk-affected areas. Cloud space monitors and predicts the person's panic health and symptoms using the SARIMA model. Furthermore, it also identifies risk-prone regions in the affected place using Geographical Population Analysis. The performance evaluation acknowledges the efficiency related to panic health determination and prediction based on the SARIMA with risks mapping accuracy. The proposed system provides an efficient on time evacuation with priority from risk-affected places that protect people from attacks due to panic and infection caused by COVID-19.

11.
Childs Nerv Syst ; 36(4): 841-845, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32055976

RESUMEN

INTRODUCTION: Drug-resistant seizures due to hemimegalencephaly in neonates and infants are a unique surgical and anesthesia challenge. While early surgery in these patients may predict a better seizure control, a lower body weight, limited blood volume, and surgical blood loss may make hemispherectomy prohibitive. METHODS: Two infants (weight, 8.7 kg and 3.7 kg) underwent interhemispheric vertical hemispherotomy with endoscope assistance. In the first case, during the lateral disconnection, excessive bleeding prompted the surgeon to coagulate the lenticulostriate arteries at the origin from the middle cerebral artery to reduce bleeding. In the second infant, the lenticulostriate arteries were coagulated before initiating the lateral disconnection. RESULTS: In both infants, the blood loss from lateral dissection was reduced by coagulation of lenticulostriate arteries. CONCLUSION: The authors suggest that early coagulation of the lenticulostriate arteries is a useful strategy to minimize blood loss in low-weight infants undergoing hemispherotomy.


Asunto(s)
Hemimegalencefalia , Hemisferectomía , Hemimegalencefalia/etiología , Hemimegalencefalia/cirugía , Humanos , Lactante , Recién Nacido , Imagen por Resonancia Magnética , Convulsiones/etiología , Resultado del Tratamiento
12.
Pediatr Neurosurg ; 55(1): 62-66, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31770757

RESUMEN

INTRODUCTION: Sellar/suprasellar arachnoid cysts are infrequent nonneoplastic cystic lesions that account for approximately 1% of all arachnoid cysts. While various surgical treatment options have been proposed for symptomatic lesions, treatment guidelines regarding the management of asymptomatic sellar/suprasellar arachnoid cysts remain to be elucidated. This case series aims to provide a better insight into the management and outcomes of such lesions. CASE PRESENTATION: We discuss 2 pediatric patients diagnosed with sellar/suprasellar arachnoid cysts who remained asymptomatic and demonstrated spontaneous gradual resolution of their arachnoid cysts on subsequent imaging studies. CONCLUSION: Review of the literature identified only a handful of previously reported cases of spontaneously disappearing suprasellar arachnoid cysts. There might be a role for conservative management of sellar/suprasellar arachnoid cysts in certain patients who remain asymptomatic.


Asunto(s)
Quistes Aracnoideos/terapia , Quistes Aracnoideos/diagnóstico por imagen , Niño , Humanos , Imagen por Resonancia Magnética , Masculino , Remisión Espontánea
13.
Pediatr Neurosurg ; 55(1): 51-53, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31661699

RESUMEN

The mitogen-activated protein kinase (MAPK) pathway consists of the Ras/Raf/MEK/ERK signaling cascade, and its upregulation plays a major role in the pathogenesis of pediatric astrocytomas and molecular inhibitors of this pathway including trametinib and dabrafenib have been tested in early-phase clinical trials and used by pediatric oncologists in children with BRAF-mutated gliomas. We report a clinical case where a child with progressive BRAF-mutated glioma developed an uncommon and difficult to manage complication - pneumocephalus from intracranial air entry and trapping through dehisced surgical wounds and preexisting skull burr holes. The patient's wound breakdown coincided with skin toxicity from MEK inhibitor therapy. With increasing use of targeted molecular inhibitors in pediatric neuro-oncology, this case illustrates the potentially complicated course of MEK inhibitor therapy in patients with scalp surgical wounds and burr holes that were placed within few weeks from initiation of drug therapy, especially if patients have additional factors that can contribute to poor wound healing such as use of steroids and malnutrition.


Asunto(s)
Glioma/tratamiento farmacológico , Neumocéfalo/etiología , Inhibidores de Proteínas Quinasas/efectos adversos , Piridonas/efectos adversos , Pirimidinonas/efectos adversos , Dehiscencia de la Herida Operatoria/etiología , Preescolar , Femenino , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos
14.
Epilepsia ; 60(2): 255-267, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30710356

RESUMEN

OBJECTIVE: The strength of presurgical language mapping using electrocorticography (ECoG) is its outstanding signal fidelity and temporal resolution, but the weakness includes limited spatial sampling at an individual patient level. By averaging naming-related high-gamma activity at nonepileptic regions across a large number of patients, we provided the functional cortical atlases animating the neural dynamics supporting visual-object and auditory-description naming at the whole brain level. METHODS: We studied 79 patients who underwent extraoperative ECoG recording as epilepsy presurgical evaluation, and generated time-frequency plots and animation videos delineating the dynamics of naming-related high-gamma activity at 70-110 Hz. RESULTS: Naming task performance elicited high-gamma augmentation in domain-specific lower-order sensory areas and inferior-precentral gyri immediately after stimulus onset. High-gamma augmentation subsequently involved widespread neocortical networks with left hemisphere dominance. Left posterior temporal high-gamma augmentation at several hundred milliseconds before response onset exhibited a double dissociation; picture naming elicited high-gamma augmentation preferentially in regions medial to the inferior-temporal gyrus, whereas auditory naming elicited high-gamma augmentation more laterally. The left lateral prefrontal regions including Broca's area initially exhibited high-gamma suppression subsequently followed by high-gamma augmentation at several hundred milliseconds before response onset during both naming tasks. Early high-gamma suppression within Broca's area was more intense during picture compared to auditory naming. Subsequent lateral-prefrontal high-gamma augmentation was more intense during auditory compared to picture naming. SIGNIFICANCE: This study revealed contrasting characteristics in the spatiotemporal dynamics of naming-related neural modulations between tasks. The dynamic atlases of visual and auditory language might be useful for planning of epilepsy surgery. Differential neural activation well explains some of the previously reported observations of domain-specific language impairments following resective epilepsy surgery. Video materials might be beneficial for the education of lay people about how the brain functions differentially during visual and auditory naming.


Asunto(s)
Encéfalo/fisiopatología , Epilepsias Parciales/fisiopatología , Epilepsia/fisiopatología , Lenguaje , Adolescente , Adulto , Mapeo Encefálico/métodos , Niño , Preescolar , Electrocorticografía/métodos , Electrodos Implantados , Electroencefalografía/métodos , Femenino , Humanos , Masculino , Adulto Joven
15.
Childs Nerv Syst ; 35(8): 1341-1349, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31243582

RESUMEN

PURPOSE: To evaluate microsurgical trans-sylvian trans-ventricular anatomical hemispherectomy with regard to seizure outcome, risk of hydrocephalus, blood loss, and risk of chronic hemosiderosis in patients with intractable seizures selected for surgery using current preoperative assessment techniques. METHODS: Out of 86 patients who underwent hemispherectomy between February 2000 and April 2019, by a single surgeon, at a tertiary care referral center, 77 patients (ages 0.2-20 years; 40 females) who had an anatomical hemispherectomy were analyzed. Five of these were 'palliative' surgeries. One-stage anatomical hemispherectomy was performed in 55 children, two-stage anatomical hemispherectomy after extraoperative intracranial monitoring in 16, and six hemispherectomies were done following failed previous resection. Mean follow-up duration was 5.7 years (range 1-16.84 years). Forty-six patients had postoperative MRI scans. RESULTS: Ninety percent of children with non-palliative hemispherectomy achieved ILAE Class-1 outcome. Twenty-seven patients were no longer taking anticonvulsant medications. Surgical failures (n = 4) included one patient with previous meningoencephalitis, one with anti-GAD antibody encephalitis, one with idiopathic neonatal thalamic hemorrhage, and one with extensive tuberous sclerosis. There were no failures among patients with malformations of cortical development. Estimated average blood loss during surgery was 387 ml. Ten (21%) children developed hydrocephalus and required a shunt following one-stage hemispherectomy, whereas 10 (50%) patients developed hydrocephalus among those who had extraoperative intracranial monitoring. Only 20% of the shunts malfunctioned in the first year. Early malfunctions were related to the valve and later to fracture disconnection of the shunt. One patent had a traumatic subdural hematoma. None of the patients developed clinical signs of chronic 'superficial cerebral hemosiderosis' nor was there evidence of radiologically persistent chronic hemosiderosis in patients who had postoperative MRI imaging. CONCLUSION: Surgical results of anatomical hemispherectomy are excellent in carefully selected cases. Post-operative complications of hydrocephalus and intraoperative blood loss are comparable to those reported for hemispheric disconnective surgery (hemispherotomy). The rate of shunt malfunction was less than that reported for patients with hydrocephalus of other etiologies Absence of chronic 'superficial hemosiderosis', even on long-term follow-up, suggests that anatomical hemispherectomy should be revisited as a viable option in patients with intractable seizures and altered anatomy such as in malformations of cortical development, a group that has a reported high rate of seizure recurrence related to incomplete disconnection following hemispheric disconnective surgery.


Asunto(s)
Epilepsia Refractaria/cirugía , Hemisferectomía/efectos adversos , Hemisferectomía/métodos , Complicaciones Posoperatorias/etiología , Adolescente , Pérdida de Sangre Quirúrgica , Niño , Preescolar , Femenino , Hemosiderosis/epidemiología , Hemosiderosis/etiología , Humanos , Hidrocefalia/epidemiología , Hidrocefalia/etiología , Lactante , Masculino , Complicaciones Posoperatorias/epidemiología , Adulto Joven
16.
Neurobiol Dis ; 109(Pt A): 76-87, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28993242

RESUMEN

Tuberous sclerosis complex (TSC) is characterized by hamartomatous lesions in various organs and arises due to mutations in the TSC1 or TSC2 genes. TSC mutations lead to a range of neurological manifestations including epilepsy, cognitive impairment, autism spectrum disorders (ASD), and brain lesions that include cortical tubers. There is evidence that seizures arise at or near cortical tubers, but it is unknown why some tubers are epileptogenic while others are not. We have previously reported increased tryptophan metabolism measured with α[11C]-methyl-l-tryptophan (AMT) positron emission tomography (PET) in epileptogenic tubers in approximately two-thirds of patients with tuberous sclerosis and intractable epilepsy. However, the underlying mechanisms leading to seizure onset in TSC remain poorly characterized. MicroRNAs are enriched in the brain and play important roles in neurodevelopment and brain function. Recent reports have shown aberrant microRNA expression in epilepsy and TSC. In this study, we performed microRNA expression profiling in brain specimens obtained from TSC patients undergoing epilepsy surgery for intractable epilepsy. Typically, in these resections several non-seizure onset tubers are resected together with the seizure-onset tubers because of their proximity. We directly compared seizure onset tubers, with and without increased tryptophan metabolism measured with PET, and non-onset tubers to assess the role of microRNAs in epileptogenesis associated with these lesions. Whether a particular tuber was epileptogenic or non-epileptogenic was determined with intracranial electrocorticography, and tryptophan metabolism was measured with AMT PET. We identified a set of five microRNAs (miR-142-3p, 142-5p, 223-3p, 200b-3p and 32-5p) that collectively distinguish among the three primary groups of tubers: non-onset/AMT-cold (NC), onset/AMT-cold (OC), and onset/AMT-hot (OH). These microRNAs were significantly upregulated in OH tubers compared to the other two groups, and microRNA expression was most significantly associated with AMT-PET uptake. The microRNAs target a group of genes enriched for synaptic signaling and epilepsy risk, including SLC12A5, SYT1, GRIN2A, GRIN2B, KCNB1, SCN2A, TSC1, and MEF2C. We confirmed the interaction between miR-32-5p and SLC12A5 using a luciferase reporter assay. Our findings provide a new avenue for subsequent mechanistic studies of tuber epileptogenesis in TSC.


Asunto(s)
MicroARNs/metabolismo , Tomografía de Emisión de Positrones , Convulsiones/metabolismo , Triptófano/metabolismo , Esclerosis Tuberosa/diagnóstico por imagen , Esclerosis Tuberosa/metabolismo , Niño , Preescolar , Femenino , Expresión Génica , Perfilación de la Expresión Génica , Humanos , Lactante , Masculino , Convulsiones/complicaciones , Convulsiones/diagnóstico por imagen , Convulsiones/genética , Simportadores/metabolismo , Triptófano/análogos & derivados , Triptófano/análisis , Esclerosis Tuberosa/complicaciones , Esclerosis Tuberosa/genética
17.
Epilepsia ; 59(10): 1954-1965, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30146766

RESUMEN

OBJECTIVE: We hypothesized that the modulation index (MI), a summary measure of the strength of phase-amplitude coupling between high-frequency activity (>150 Hz) and the phase of slow waves (3-4 Hz), would serve as a useful interictal biomarker for epilepsy presurgical evaluation. METHODS: We investigated 123 patients who underwent focal cortical resection following extraoperative electrocorticography recording and had at least 1 year of postoperative follow-up. We examined whether consideration of MI would improve the prediction of postoperative seizure outcome. MI was measured at each intracranial electrode site during interictal slow-wave sleep. We compared the accuracy of prediction of patients achieving International League Against Epilepsy class 1 outcome between the full multivariate logistic regression model incorporating MI in addition to conventional clinical, seizure onset zone (SOZ), and neuroimaging variables, and the reduced logistic regression model incorporating all variables other than MI. RESULTS: Ninety patients had class 1 outcome at the time of most recent follow-up (mean follow-up = 5.7 years). The full model had a noteworthy outcome predictive ability, as reflected by regression model fit R2 of 0.409 and area under the curve (AUC) of receiver operating characteristic plot of 0.838. Incomplete resection of SOZ (P < 0.001), larger number of antiepileptic drugs at the time of surgery (P = 0.007), and larger MI in nonresected tissues relative to that in resected tissue (P = 0.020) were independently associated with a reduced probability of class 1 outcome. The reduced model had a lower predictive ability as reflected by R2 of 0.266 and AUC of 0.767. Anatomical variability in MI existed among nonepileptic electrode sites, defined as those unaffected by magnetic resonance imaging lesion, SOZ, or interictal spike discharges. With MI adjusted for anatomical variability, the full model yielded the outcome predictive ability of R2 of 0.422, AUC of 0.844, and sensitivity/specificity of 0.86/0.76. SIGNIFICANCE: MI during interictal recording may provide useful information for the prediction of postoperative seizure outcome.


Asunto(s)
Mapeo Encefálico , Ondas Encefálicas/fisiología , Epilepsia/fisiopatología , Epilepsia/cirugía , Adolescente , Adulto , Niño , Preescolar , Electroencefalografía , Epilepsia/diagnóstico por imagen , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Modelos Logísticos , Imagen por Resonancia Magnética , Masculino , Curva ROC , Estudios Retrospectivos , Sueño/fisiología , Resultado del Tratamiento , Adulto Joven
18.
Brain ; 140(5): 1351-1370, 2017 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-28334963

RESUMEN

We have provided 3-D and 4D mapping of speech and language function based upon the results of direct cortical stimulation and event-related modulation of electrocorticography signals. Patients estimated to have right-hemispheric language dominance were excluded. Thus, 100 patients who underwent two-stage epilepsy surgery with chronic electrocorticography recording were studied. An older group consisted of 84 patients at least 10 years of age (7367 artefact-free non-epileptic electrodes), whereas a younger group included 16 children younger than age 10 (1438 electrodes). The probability of symptoms transiently induced by electrical stimulation was delineated on a 3D average surface image. The electrocorticography amplitude changes of high-gamma (70-110 Hz) and beta (15-30 Hz) activities during an auditory-naming task were animated on the average surface image in a 4D manner. Thereby, high-gamma augmentation and beta attenuation were treated as summary measures of cortical activation. Stimulation data indicated the causal relationship between (i) superior-temporal gyrus of either hemisphere and auditory hallucination; (ii) left superior-/middle-temporal gyri and receptive aphasia; (iii) widespread temporal/frontal lobe regions of the left hemisphere and expressive aphasia; and (iv) bilateral precentral/left posterior superior-frontal regions and speech arrest. On electrocorticography analysis, high-gamma augmentation involved the bilateral superior-temporal and precentral gyri immediately following question onset; at the same time, high-gamma activity was attenuated in the left orbitofrontal gyrus. High-gamma activity was augmented in the left temporal/frontal lobe regions, as well as left inferior-parietal and cingulate regions, maximally around question offset, with high-gamma augmentation in the left pars orbitalis inferior-frontal, middle-frontal, and inferior-parietal regions preceded by high-gamma attenuation in the contralateral homotopic regions. Immediately before verbal response, high-gamma augmentation involved the posterior superior-frontal and pre/postcentral regions, bilaterally. Beta-attenuation was spatially and temporally correlated with high-gamma augmentation in general but with exceptions. The younger and older groups shared similar spatial-temporal profiles of high-gamma and beta modulation; except, the younger group failed to show left-dominant activation in the rostral middle-frontal and pars orbitalis inferior-frontal regions around stimulus offset. The human brain may rapidly and alternately activate and deactivate cortical areas advantageous or obtrusive to function directed toward speech and language at a given moment. Increased left-dominant activation in the anterior frontal structures in the older age group may reflect developmental consolidation of the language system. The results of our functional mapping may be useful in predicting, across not only space but also time and patient age, sites specific to language function for presurgical evaluation of focal epilepsy.


Asunto(s)
Mapeo Encefálico/métodos , Corteza Cerebelosa/fisiología , Electrocorticografía/métodos , Epilepsia/fisiopatología , Imagenología Tridimensional/métodos , Lenguaje , Habla/fisiología , Adolescente , Adulto , Factores de Edad , Ondas Encefálicas/fisiología , Niño , Preescolar , Estimulación Eléctrica , Electrodos Implantados , Humanos , Adulto Joven
19.
Childs Nerv Syst ; 34(4): 787-789, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29294141

RESUMEN

INTRODUCTION: This case examines a unique, longitudinal presentation of an abandoned, migrating VP shunt which presents as multiple complications, including a weeping abscess in the patients back. We believe that the latter complication was potentially caused by the wound from the patient's previous history of spinal fusion surgery. CASE PRESENTATION: The patient presents with an associated type 2 Chiari malformation, hydrocephalus, and a previous history of posterior spinal fusion (T4-L5 anterior fusion and T2-L5 posterior fusion) at age 11. The patient had undergone shunt revisions in early adolescence as well. At 22, the patient is admitted into emergency care due to recurrent infections caused by a migrating VP shunt. Due to complications in corrective surgery at the time, the shunt was forced to be abandoned. This resulted in the most recent presentation of a weeping abscess at the patient's spinal fusion surgery wound; the culprit was the abandoned, migrating VP shunt.. MANAGEMENT/OUTCOME: An initial course of broad-spectrum antibiotics was started. However, the abscess continued to recur. Eventually, the catheter was surgically removed, a tailored antibiotic regiment was started, and a 6-month patient follow-up was performed. The patient is no longer symptomatic and off of antibiotics. DISCUSSION: In abandoned VP shunts, migration into a non-sterile cavity dictates prompt removal, especially after symptoms of infection present. Additionally, careful monitoring for signs of peritonitis or other symptoms for a dedicated period of time is necessary. To the authors' best knowledge, this is the first case of an occult shunt migration through the patient's back that presented with a weeping abscess.


Asunto(s)
Malformación de Arnold-Chiari/cirugía , Migración de Cuerpo Extraño/etiología , Prótesis e Implantes/efectos adversos , Espina Bífida Oculta/cirugía , Fusión Vertebral/efectos adversos , Derivación Ventriculoperitoneal/efectos adversos , Adulto , Malformación de Arnold-Chiari/complicaciones , Migración de Cuerpo Extraño/diagnóstico por imagen , Humanos , Masculino , Espina Bífida Oculta/complicaciones , Fusión Vertebral/métodos , Tomógrafos Computarizados por Rayos X
20.
J Med Syst ; 42(10): 187, 2018 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-30173290

RESUMEN

Kyasanur Forest Disease (KFD) is a life-threatening tick-borne viral infectious disease endemic to South Asia and has been taking so many lives every year in the past decade. But recently, this disease has been witnessed in other regions to a large extent and can become an epidemic very soon. In this paper, a new fog computing based e-Healthcare framework has been proposed to monitor the KFD infected patients in an early phase of infection and control the disease outbreak. For ensuring high prediction rate, a novel Extremal Optimization tuned Neural Network (EO-NN) classification algorithm has been developed using hybridization of the extremal optimization with the feed-forward neural network. Additionally, a location based alert system has also been suggested to provide the global positioning system (GPS)-based location information of each KFD infected user and the risk-prone zones as early as possible to prevent the outbreak. Furthermore, a comparative study of proposed EO-NN with state of art classification algorithms has been carried out and it can be concluded that EO-NN outperforms others with an average accuracy of 91.56%, a sensitivity of 91.53% and a specificity of 97.13% respectively in classification and accurate identification of risk-prone areas.


Asunto(s)
Brotes de Enfermedades , Enfermedad del Bosque de Kyasanur/diagnóstico , Redes Neurales de la Computación , Algoritmos , Teorema de Bayes , Humanos
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