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OBJECTIVE: Laser interstitial thermal therapy (LITT) is a minimally invasive surgery for mesial temporal lobe epilepsy (mTLE), but the effects of individual patient anatomy and location of ablation volumes affect seizure outcomes. The purpose of this study is to see if features of individual patient structural connectomes predict surgical outcomes after LITT for mTLE. METHODS: This is a retrospective analysis of seizure outcomes of LITT for mTLE in 24 patients. We use preoperative diffusion tensor imaging (DTI) to simulate changes in structural connectivity after laser ablation. A two-step machine-learning algorithm is applied to predict seizure outcomes from the change in connectomic features after surgery. RESULTS: Although node-based network features such as clustering coefficient and betweenness centrality have some predictive value, changes in connection strength between mesial temporal regions predict seizure outcomes significantly better. Changes in connection strength between the entorhinal cortex (EC), and the insula, hippocampus, and amygdala, as well as between the temporal pole and hippocampus, predict Engel Class I outcomes with an accuracy of 88%. Analysis of the ablation location, as well as simulated, alternative ablations, reveals that a more medial, anterior, and inferior ablation volume is associated with a greater effect on these connections, and potentially on seizure outcomes. SIGNIFICANCE: Our results indicate (1) that seizure outcomes can be retrospectively predicted with excellent accuracy using changes in structural connectivity, and (2) that favorable connectomic changes are associated with an ablation volume involving relatively mesial, anterior, and inferior locations. These results may provide a framework whereby individual pre-operative structural connectomes can be used to optimize ablation volumes and improve outcomes in LITT for mTLE.
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Conectoma , Epilepsia del Lóbulo Temporal , Terapia por Láser , Imagen de Difusión Tensora , Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Epilepsia del Lóbulo Temporal/cirugía , Libertad , Hipocampo/cirugía , Humanos , Terapia por Láser/métodos , Rayos Láser , Imagen por Resonancia Magnética/métodos , Estudios Retrospectivos , Convulsiones/cirugía , Resultado del TratamientoRESUMEN
MRI-guided laser interstitial thermal therapy (MgLiTT) uses a narrow diameter cannula to stereotactically target and heat deeper cerebral structures. This technique produces a precise lesion in the brain with great reliability because the localized tissue temperature change is monitored in real time. Because MgLiTT minimizes injury to surrounding brain, it appears to have a lower risk of affecting normal neurological function, and because it is done through a burr hole, there is less operative risk, less discomfort, and shorter hospitalizations. It is FDA approved for soft tissue ablation and is being increasingly applied to the surgical treatment of epilepsy, especially when seizures arise from deeper structures such as the hippocampus, amygdala, or discrete dysplastic tissue such as hypothalamic hamartomas. Mesial temporal epilepsy is the most frequently encountered surgically remedial epilepsy suitable for MgLiTT, particularly when there is unilateral hippocampal sclerosis. There is emerging evidence that it can be effective for eliminating seizures in this type of epilepsy, and that it has a lower risk of cognitive deficits than anterior temporal lobectomy.
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Encéfalo/cirugía , Epilepsia del Lóbulo Temporal/cirugía , Terapia por Láser/métodos , Humanos , Imagen por Resonancia Magnética , Complicaciones Posoperatorias , Técnicas Estereotáxicas , Resultado del TratamientoRESUMEN
The learning of a motor task is known to be improved by sleep, and sleep spindles are thought to facilitate this learning by enabling synaptic plasticity. In this study subjects implanted with electrocorticography (ECoG) arrays for long-term epilepsy monitoring were trained to control a cursor on a computer screen by modulating either the high-gamma or mu/beta power at a single electrode located over the motor or premotor area. In all trained subjects, spindle density in posttraining sleep was increased with respect to pretraining sleep in a remarkably spatially specific manner. The pattern of increased spindle activity reflects the functionally specific regions that were involved in learning of a highly novel and salient task during wakefulness, supporting the idea that sleep spindles are involved in learning to use a motor-based brain-computer interface device.
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Interfaces Cerebro-Computador , Sueño/fisiología , Adolescente , Adulto , Análisis por Conglomerados , Electrodos , Femenino , Humanos , Masculino , Adulto JovenRESUMEN
This article summarizes the state-of-science knowledge regarding the associations between hypnosis and brain oscillations. Brain oscillations represent the combined electrical activity of neuronal assemblies, usually measured as specific frequencies representing slower (delta, theta, alpha) and faster (beta, gamma) oscillations. Hypnosis has been most closely linked to power in the theta band and changes in gamma activity. These oscillations are thought to play a critical role in both the recording and recall of declarative memory and emotional limbic circuits. The authors propose that this role may be the mechanistic link between theta (and perhaps gamma) oscillations and hypnosis, specifically, that the increases in theta oscillations and changes in gamma activity observed with hypnosis may underlie some hypnotic responses. If these hypotheses are supported, they have important implications for both understanding the effects of hypnosis and for enhancing response to hypnotic treatments.
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Ondas Encefálicas/fisiología , Encéfalo/fisiología , Hipnosis , Electroencefalografía , Humanos , Ritmo TetaRESUMEN
In this article, we summarize the state-of-science knowledge regarding the associations between hypnosis and brain oscillations. Brain oscillations represent the combined electrical activity of neuronal assemblies, and are usually measured as specific frequencies representing slower (delta, theta, alpha) and faster (beta, gamma) oscillations. Hypnosis has been most closely linked to power in the theta band and changes in gamma activity. These oscillations are thought to play a critical role in both the recording and recall of declarative memory and emotional limbic circuits. Here we propose that it is this role that may be the mechanistic link between theta (and perhaps gamma) oscillations and hypnosis; specifically that theta oscillations may facilitate, and that changes in gamma activity observed with hypnosis may underlie, some hypnotic responses. If these hypotheses are supported, they have important implications for both understanding the effects of hypnosis, and for enhancing response to hypnotic treatments.
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OBJECTIVES: The objective of this study was to examine the associations between baseline electroencephalogram (EEG)-assessed brain oscillations and subsequent response to four neuromodulatory treatments. Based on available research, we hypothesized that baseline theta oscillations would prospectively predict response to hypnotic analgesia. Analyses involving other oscillations and the other treatments (meditation, neurofeedback, and both active and sham transcranial direct current stimulation) were viewed as exploratory, given the lack of previous research examining brain oscillations as predictors of response to these other treatments. DESIGN: Randomized controlled study of single sessions of four neuromodulatory pain treatments and a control procedure. METHODS: Thirty individuals with spinal cord injury and chronic pain had their EEG recorded before each session of four active treatments (hypnosis, meditation, EEG biofeedback, transcranial direct current stimulation) and a control procedure (sham transcranial direct stimulation). RESULTS: As hypothesized, more presession theta power was associated with greater response to hypnotic analgesia. In exploratory analyses, we found that less baseline alpha power predicted pain reduction with meditation. CONCLUSIONS: The findings support the idea that different patients respond to different pain treatments and that between-person treatment response differences are related to brain states as measured by EEG. The results have implications for the possibility of enhancing pain treatment response by either 1) better patient/treatment matching or 2) influencing brain activity before treatment is initiated in order to prepare patients to respond. Research is needed to replicate and confirm the findings in additional samples of individuals with chronic pain.
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Encéfalo/fisiología , Dolor Crónico/terapia , Manejo del Dolor/métodos , Traumatismos de la Médula Espinal/complicaciones , Adulto , Anciano , Estudios Cruzados , Electroencefalografía , Femenino , Humanos , Hipnosis/métodos , Masculino , Meditación/métodos , Persona de Mediana Edad , Neurorretroalimentación/métodos , Manejo del Dolor/psicología , Estimulación Transcraneal de Corriente Directa/métodos , Adulto JovenRESUMEN
AIMS: To describe the technique, indications, and utility of intraoperative ECoG monitoring during various surgeries for medically intractable epilepsy. METHODS: Literature was reviewed to obtain published results on using intraoperative ECoG techniques for the surgical treatment of medically intractable epilepsy of various underlying aetiologies. RESULTS General intraoperative ECoG techniques were described, including effects of anaesthetic agents on intraoperative ECoG signals. Use of intraoperative ECoG in temporal lobe epilepsy with mesial temporal sclerosis (MTS) is generally considered not necessary, whereas intraoperative ECoG in temporal lobe epilepsy without mesial temporal sclerosis may provide useful information. Intraoperative ECoG in extra-temporal epilepsy with structural lesions may facilitate resection, whereas the use of intraoperative ECoG in extra-temporal epilepsy without a structural lesion is more controversial. CONCLUSIONS: Intraoperative ECoG is a useful technique to be employed in surgical treatment of medically intractable epilepsy. However, its effectiveness may vary depending on the underlying pathological causes of the seizures.
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Mapeo Encefálico/métodos , Encéfalo/cirugía , Electroencefalografía/métodos , Epilepsia/cirugía , Encéfalo/fisiopatología , Epilepsia/fisiopatología , Humanos , Monitoreo Intraoperatorio/métodosRESUMEN
Chronic pain, usually refractory to analgesics, is a significant problem for many individuals with spinal cord injury (SCI). Preliminary studies suggest that electroencephalography (EEG) biofeedback (also known as neurofeedback, NF) has the potential to help patients with otherwise refractory chronic pain. However, there remain many unanswered questions about the effects and mechanisms of this treatment. We studied 13 individuals with SCI and chronic pain with NF. Ten of the 13 individuals completed 4 sessions each of three different neurofeedback protocols assigned in random order for a total of 12 NF sessions. All three protocols had similar immediate effects on pain intensity. In addition, the participants reported modest pre- to post-treatment decreases in worst pain and pain unpleasantness following completion of the 12 NF sessions. These improvements were maintained at 3-month follow-up. The majority of the participants felt they benefited from and were satisfied with the treatment. No significant effects on measures of other outcome domains (sleep quality, pain interference and fatigue) were observed, although there was a non-significant trend for an increase in fatigue. Finally, pre- to post-treatment changes in EEG bandwidth activity, consistent with the training protocols, were observed in θ and α but not ß frequencies. The findings provide preliminary support for the potential efficacy of NF for the treatment of SCI-related pain, and suggest that further clinical studies are warranted.
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Dolor Crónico/terapia , Neurorretroalimentación/métodos , Manejo del Dolor/métodos , Traumatismos de la Médula Espinal/complicaciones , Médula Espinal/fisiopatología , Adulto , Anciano , Atención , Dolor Crónico/etiología , Dolor Crónico/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Traumatismos de la Médula Espinal/fisiopatología , Resultado del TratamientoRESUMEN
Different psychological chronic pain treatments benefit some individuals more than others. Understanding the factors that are associated with treatment response-especially when those factors differ between treatments-may inform more effective patient-treatment matching. This study aimed to identify variables that moderate treatment response to 4 psychological pain interventions in a sample of adults with low back pain or chronic pain associated with multiple sclerosis, spinal cord injury, acquired amputation, or muscular dystrophy (N = 173). The current study presents the results from secondary exploratory analyses using data from a randomized controlled clinical trial which compared the effects of 4 sessions of cognitive therapy (CT), hypnosis focused on pain reduction (HYP), hypnosis focused on changing pain-related cognitions and beliefs (HYP-CT), and a pain education control condition (ED). The analyses tested the effects of 7 potential treatment moderators. Measures of primary (pain intensity) and secondary (pain interference, depression severity) outcome domains were administered before and after the pain treatments, and potential moderators (catastrophizing, hypnotizability, and electroencephalogram (EEG)-assessed oscillation power across five bandwidths) were assessed at pre-treatment. Moderator effects were tested fitting regression analyses to pre- to post-treatment changes in the three outcome variables. The study findings, while preliminary, support the premise that pre-treatment measures of hypnotizability and EEG brain activity predict who is more (or less) likely to respond to different psychological pain treatments. If additional research replicates the findings, it may be possible to better match patients to their more individually suitable treatment, ultimately improving pain treatment outcomes. PERSPECTIVE: Pre-treatment measures of hypnotizability and EEG-assessed brain activity predicted who was more (or less) likely to respond to different psychological pain treatments. If these findings are replicated in future studies, they could inform the development of patient-treatment matching algorithms.
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Dolor Crónico , Terapia Cognitivo-Conductual , Hipnosis , Adulto , Humanos , Dolor Crónico/terapia , Dolor Crónico/psicología , Terapia Cognitivo-Conductual/métodos , Manejo del Dolor/métodos , Resultado del Tratamiento , Hipnosis/métodosRESUMEN
OBJECTIVES: The purpose of this report was to study the incidence of sudden unexpected death in epilepsy (SUDEP) after laser interstitial thermal therapy (LITT) for drug-resistant epilepsy (DRE). METHODS: A prospective observational study of consecutive patients treated with LITT between 2013 and 2021 was conducted. The primary outcome was the occurrence of SUDEP during postoperative follow-up. Surgical outcome was classified according to the Engel scale. RESULTS: There were 5 deaths, including 4 SUDEPs, among 135 patients with a median follow-up duration of 3.5 (range 0.1-9.0) years and a total of 501.3 person-years at risk. The estimated incidence of SUDEP was 8.0 (95% CI 2.2-20.4) per 1,000 person-years. Three SUDEPs occurred in patients with poor seizure outcomes, whereas 1 patient was seizure-free. Compared with pooled historical data, SUDEP occurred at a higher rate than in cohorts treated with resective surgery and at a rate similar to nonsurgical controls. DISCUSSION: SUDEP occurred early and late after mesial temporal LITT. The SUDEP rate was comparable with rates reported in epilepsy surgery candidates who did not receive intervention. These findings reinforce targeting seizure freedom to decrease SUDEP risk, including early consideration for further intervention. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that LITT is not effective in reducing SUDEP incidence in patients with DRE.
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Epilepsia Refractaria , Epilepsia , Terapia por Láser , Muerte Súbita e Inesperada en la Epilepsia , Humanos , Epilepsia/cirugía , Epilepsia Refractaria/cirugía , Convulsiones/cirugía , Rayos LáserRESUMEN
OBJECT: Posttraumatic epilepsy (PTE) is a common cause of medically intractable epilepsy. While much of PTE is extratemporal, little is known about factors associated with good outcomes in extratemporal resections in medically intractable PTE. The authors investigated and characterized the long-term outcome and patient factors associated with outcome in this population. METHODS: A single-institution retrospective query of all epilepsy surgeries at Regional Epilepsy Center at the University of Washington was performed for a 17-year time span with search terms indicative of trauma or brain injury. The query was limited to adult patients who underwent an extratemporal resection (with or without temporal lobectomy), in whom no other cause of epilepsy could be identified, and for whom minimum 1-year follow-up data were available. Surgical outcomes (in terms of seizure reduction) and clinical data were analyzed and compared. RESULTS: Twenty-one patients met inclusion and exclusion criteria. In long-term follow-up 6 patients (28%) were seizure-free and an additional 6 (28%) had a good outcome of 2 or fewer seizures per year. Another 5 patients (24%) experienced a reduction in seizures, while only 4 (19%) did not attain significant benefit. The presence of focal encephalomalacia on imaging was associated with good or excellent outcomes in 83%. In 8 patients with the combination of encephalomalacia and invasive intracranial EEG, 5 (62.5%) were found to be seizure free. Normal MRI examinations preoperatively were associated with worse outcomes, particularly when combined with multifocal or poorly localized EEG findings. Two patients suffered complications but none were life threatening or disabling. CONCLUSIONS: Many patients with extratemporal PTE can achieve good to excellent seizure control with epilepsy surgery. The risks of complications are acceptably low. Patients with focal encephalomalacia on MRI generally do well. Excellent outcomes can be achieved when extratemporal resection is guided by intracranial EEG electrodes defining the extent of resection.
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Epilepsia/etiología , Epilepsia/cirugía , Lóbulo Temporal/cirugía , Resultado del Tratamiento , Adolescente , Adulto , Lesiones Encefálicas/complicaciones , Electroencefalografía , Femenino , Humanos , Estudios Longitudinales , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tomografía Computarizada de Emisión de Fotón Único , Tomografía Computarizada por Rayos X , Adulto JovenRESUMEN
BACKGROUND: MRI-guided laser interstitial thermal therapy (MRgLITT) for mesial temporal lobe epilepsy is a safe, minimally invasive alternative to traditional surgical approaches. Prognostic factors associated with efficacy are debated; preoperative epilepsy duration and semiology seem to be important variables. OBJECTIVE: To determine whether acute postoperative seizure (APOS) after MRgLITT for mesial temporal lobe epilepsy is associated with seizure freedom/Engel class outcome at 1 year. METHODS: A single-institution retrospective study including adults undergoing first time MRgLITT for mesial temporal lobe epilepsy (2010-2019) with ≥1-year follow-up. Preoperative data included sex, epilepsy duration, number of antiepileptics attempted, weekly seizure frequency, seizure semiology, and radiographically verified anatomic lesion at seizure focus. Postoperative data included clinical detection of APOS within 7 days postoperatively, and immediate amygdala, hippocampal, entorhinal, and parahippocampal residual volumes determined using quantitative imaging postprocessing. Primary outcome was seizure freedom/Engel classification 1 year postoperatively. RESULTS: Of 116 patients, 53% (n = 61) were female, with an average epilepsy duration of 21 (±14) years, average 6 failed antiepileptics (±3), and weekly seizure frequency of 5. APOS was associated with worse Engel class ( P = .010), conferring 6.3 times greater odds of having no improvement vs achieving seizure freedom at 1 year. Residual amygdala, hippocampal, entorhinal, and parahippocampal volumes were not statistically significant prognostic factors. CONCLUSION: APOS was associated with a lower chance of seizure freedom at 1 year post-MRgLITT for mesial temporal lobe epilepsy. Amygdala, hippocampal, entorhinal, and parahippocampal residual volumes after ablation were not significant prognostic factors.
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Epilepsia Refractaria , Epilepsia del Lóbulo Temporal , Terapia por Láser , Adulto , Anticonvulsivantes , Epilepsia Refractaria/cirugía , Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Epilepsia del Lóbulo Temporal/cirugía , Femenino , Humanos , Terapia por Láser/métodos , Rayos Láser , Imagen por Resonancia Magnética/métodos , Masculino , Estudios Retrospectivos , Convulsiones/etiología , Convulsiones/cirugía , Resultado del TratamientoRESUMEN
ABSTRACT: Effective, rigorously evaluated nonpharmacological treatments for chronic pain are needed. This study compared the effectiveness of training in hypnosis (HYP) and mindfulness meditation (MM) with an active education control (ED). Veterans (N = 328) were randomly assigned to 8 manualized, group-based, in-person sessions of HYP (n = 110), MM (n = 108), or ED (n = 110). Primary (average pain intensity [API]) and secondary outcomes were assessed at pretreatment, posttreatment, and 3 and 6 months posttreatment. Treatment effects were evaluated using linear regression, a generalized estimating equation approach, or a Fisher exact test, depending on the variable. There were no significant omnibus between-group differences in pretreatment to posttreatment change in API; however, pretreatment to posttreatment improvements in API and several secondary variables were seen for participants in all 3 conditions. Participation in MM resulted in greater decreases in API and pain interference at 6 months posttreatment relative to ED. Participation in HYP resulted in greater decreases in API, pain interference, and depressive symptoms at 3 and 6 months posttreatment compared with ED. No significant differences on outcomes between HYP and MM were detected at any time point. This study suggests that all 3 interventions provide posttreatment benefits on a range of outcomes, but the benefits of HYP and MM continue beyond the end of treatment, while the improvements associated with ED dissipate over time. Future research is needed to determine whether the between-group differences that emerged posttreatment are reliable, whether there are benefits of combining treatments, and to explore moderating and mediating factors.
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Dolor Crónico , Hipnosis , Meditación , Atención Plena , Veteranos , Dolor Crónico/terapia , Humanos , Hipnosis/métodos , Meditación/métodos , Atención Plena/métodos , Dimensión del Dolor , Resultado del TratamientoRESUMEN
ABSTRACT: The current study used data from a clinical trial to identify variables that are associated with and/or mediate the beneficial effects of 4 psychological chronic pain treatments: one teaching patients self-hypnosis to reduce pain intensity (HYP), one teaching self-hypnosis to change thoughts about pain (hypnotic cognitive therapy [HYP-CT]), one teaching cognitive restructuring skills to change thoughts about pain (cognitive therapy [CT]), and one providing education about pain (ED; included as an active control condition). Of 17 possible mechanism variables examined, and with alpha not corrected for multiple comparisons, significant between-group differences were observed for 3. Two of these (changes in beliefs about control over pain and number of days of skill practice) were supported as mediators of the beneficial effects of HYP, CT, or HYP-CT, relative to ED. Six mechanism variables evidenced significant pretreatment to post-treatment changes in the sample as a whole, without showing significant between-group differences. Pretreatment to post-treatment changes in all 6 were associated with improvements in pain interference, pain intensity, or both. In addition, participant ratings of therapeutic alliance at post-treatment were associated significantly with improvements in both pain intensity and pain interference in the sample as a whole. Thus, of the 17 possible mediators examined, there were relatively few that served as mediators for the beneficial effects of specific treatments; a larger number of variables predicted treatment outcome overall. The extent to which these variables are treatment mediators (ie, are responsible for, rather than merely associated with, treatment-related improvements) will require further research.
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Dolor Crónico , Terapia Cognitivo-Conductual , Hipnosis , Dolor Crónico/terapia , Cognición , Electroencefalografía , HumanosRESUMEN
Objective: To evaluate declarative memory outcomes in medically refractory epilepsy patients who underwent either a highly selective laser ablation of the amygdalohippocampal complex or a conventional open temporal lobe resection. Methods: Post-operative change scores were examined for verbal memory outcome in epilepsy patients who underwent stereotactic laser amygdalohippocampotomy (SLAH: n = 40) or open resection procedures (n = 40) using both reliable change index (RCI) scores and a 1-SD change metric. Results: Using RCI scores, patients undergoing open resection (12/40, 30.0%) were more likely to decline on verbal memory than those undergoing SLAH (2/40 [5.0%], p = 0.0064, Fisher's exact test). Patients with language dominant procedures were much more likely to experience a significant verbal memory decline following open resection (9/19 [47.4%]) compared to laser ablation (2/19 [10.5%], p = 0.0293, Fisher's exact test). 1 SD verbal memory decline frequently occurred in the open resection sample of language dominant temporal lobe patients with mesial temporal sclerosis (8/10 [80.0%]), although it rarely occurred in such patients after SLAH (2/14, 14.3%) (p = 0.0027, Fisher's exact test). Memory improvement occurred significantly more frequently following SLAH than after open resection. Interpretation: These findings suggest that while verbal memory function can decline after laser ablation of the amygdalohippocampal complex, it is better preserved when compared to open temporal lobe resection. Our findings also highlight that the dominant hippocampus is not uniquely responsible for verbal memory. While this is at odds with our simple and common heuristic of the hippocampus in memory, it supports the findings of non-human primate studies showing that memory depends on broader medial and lateral TL regions.
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Experimental animals' seizures are often defined arbitrarily based on duration, which may lead to misjudgement of the syndrome and failure to develop a cure. We employed a functional definition of seizures based on the clinical practice of observing epileptiform electrocorticography and simultaneous ictal behaviour, and examined post-traumatic epilepsy induced in rats by rostral parasagittal fluid percussion injury and epilepsy patients evaluated with invasive monitoring. We showed previously that rostral parasagittal fluid percussion injury induces different types of chronic recurrent spontaneous partial seizures that worsen in frequency and duration over the months post injury. However, a remarkable feature of rostral parasagittal fluid percussion injury is the occurrence, in the early months post injury, of brief (<2 s) focal, recurrent and spontaneous epileptiform electrocorticography events (EEEs) that are never observed in sham-injured animals and have electrographic appearance similar to the onset of obvious chronic recurrent spontaneous partial seizures. Simultaneous epidural-electrocorticography and scalp-electroencephalography recordings in the rat demonstrated that these short EEEs are undetectable by scalp electrocorticography. Behavioural analysis performed blinded to the electrocorticography revealed that (i) brief EEEs lasting 0.8-2 s occur simultaneously with behavioural arrest; and (ii) while behavioural arrest is part of the rat's behavioural repertoire, the probability of behavioural arrest is greatly elevated during EEEs. Moreover, spectral analysis showed that EEEs lasting 0.8-2 s occurring during periods of active behaviour with dominant theta activity are immediately followed by loss of such theta activity. We thus conclude that EEEs lasting 0.8-2 s are ictal in the rat. We demonstrate that the assessment of the time course of fluid percussion injury-induced epileptogenesis is dramatically biased by the definition of seizure employed, with common duration-based arbitrary definitions resulting in artificially prolonged latencies for epileptogenesis. Finally, we present four human examples of electrocorticography capturing short (<2 s), stereotyped, neocortically generated EEEs that occurred in the same ictal sites as obvious complex partial seizures, were electrographically similar to rat EEEs and were not noted during scalp electroencephalography. When occurring in the motor cortex, these short EEEs were accompanied by ictal behaviour detectable with simultaneous surface electromyography. These data demonstrate that short (<2 s) focal recurrent spontaneous EEEs are seizures in both rats and humans, that they are undetectable by scalp electroencephalography, and that they are typically associated with subtle and easily missed behavioural correlates. These findings define the earliest identifiable markers of progressive post-traumatic epilepsy in the rat, with implications for mechanistic and prophylactic studies, and should prompt a re-evaluation of the concept of post-traumatic silent period in both animals and humans.
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Lesiones Encefálicas/clasificación , Lesiones Encefálicas/complicaciones , Epilepsia/clasificación , Epilepsia/etiología , Convulsiones/clasificación , Adulto , Animales , Anticonvulsivantes/uso terapéutico , Conducta Animal/fisiología , Lesiones Encefálicas/fisiopatología , Resistencia a Medicamentos , Electroencefalografía , Epilepsia/fisiopatología , Epilepsia Parcial Compleja/etiología , Epilepsia Parcial Compleja/fisiopatología , Femenino , Respuesta Galvánica de la Piel/fisiología , Humanos , Masculino , Persona de Mediana Edad , Procedimientos Neuroquirúrgicos , Control de Calidad , Ratas , Ratas Sprague-Dawley , Convulsiones/fisiopatología , Terminología como Asunto , Adulto JovenRESUMEN
OBJECTIVES: To describe the protocol of a randomized controlled trial to evaluate the effectiveness and mechanisms of three behavioral interventions. METHODS: Participants will include up to 343 Veterans with chronic pain due to a broad range of etiologies, randomly assigned to one of three 8-week manualized in-person group treatments: (1) Hypnosis (HYP), (2) Mindfulness Meditation (MM), or (3) Education Control (EDU). PROJECTED OUTCOMES: The primary aim of the study is to compare the effectiveness of HYP and MM to EDU on average pain intensity measured pre- and post-treatment. Additional study aims will explore the effectiveness of HYP and MM compared to EDU on secondary outcomes (i.e., pain interference, sleep, depression, anxiety and PTSD), and the maintenance of effects at 3- and 6-months post-treatment. Participants will have electroencephalogram (EEG) assessments at pre- and post-treatment to determine if the power of specific brain oscillations moderate the effectiveness of HYP and MM (Study Aim 2) and examine brain oscillations as possible mediators of treatment effects (exploratory aim). Additional planned exploratory analyses will be performed to identify possible treatment mediators (i.e., pain acceptance, catastrophizing, mindfulness) and moderators (e.g., hypnotizability, treatment expectations, pain type, cognitive function). SETTING: The study treatments will be administered at a large Veterans Affairs Medical Center in the northwest United States. The treatments will be integrated within clinical infrastructure and delivered by licensed and credentialed health care professionals.
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Dolor Crónico/terapia , Meditación/métodos , Atención Plena/métodos , Educación del Paciente como Asunto/métodos , Veteranos , Método Doble Ciego , Electroencefalografía , Femenino , Humanos , Masculino , Proyectos de InvestigaciónRESUMEN
Chronic pain is a significant health problem worldwide with limited pharmacological treatment options. This study evaluated the relative efficacy of 4 treatment sessions each of 4 nonpharmacological treatments: (1) hypnotic cognitive therapy (using hypnosis to alter the meaning of pain); (2) standard cognitive therapy; (3) hypnosis focused on pain reduction, and (4) pain education. One hundred seventy-three individuals with chronic pain were randomly assigned to receive 4 sessions of 1 of the 4 treatments. Primary (pain intensity) and secondary outcome measures were administered by assessors unaware of treatment allocation at pretreatment, posttreatment, and 3-, 6-, and 12-month follow-up. Treatment effects were evaluated using analysis of variance, a generalized estimating equation approach, or a Fisher exact test, depending on the outcome domain examined. All 4 treatments were associated with medium to large effect size improvements in pain intensity that maintained up to 12 months posttreatment. Pretreatment to posttreatment improvements were observed across the 4 treatment conditions on the secondary outcomes of pain interference and depressive symptoms, with some return towards pretreatment levels at 12-month follow-up. No significant between-group differences emerged in omnibus analyses, and few statistically significant between-group differences emerged in the planned pairwise analyses, although the 2 significant effects that did emerge favored hypnotic cognitive therapy. Future research is needed to determine whether the significant differences that emerged are reliable.
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Dolor Crónico , Terapia Cognitivo-Conductual , Hipnosis , Adulto , Dolor Crónico/terapia , Femenino , Humanos , Hipnóticos y Sedantes , Masculino , Persona de Mediana Edad , Manejo del Dolor , Resultado del TratamientoRESUMEN
The premise of neuro-rehabilitation after injury is to access the residual capacity of the nervous system to improve function. We describe a patient who developed a quadrantopsia and drug-resistant focal epilepsy after an arteriovenous malformation hemorrhage. Thirty years later, he underwent placement of subdural electrodes for seizure mapping. Phosphenes were elicited in the blind right visual field with stimulation of occipital cortex. This case demonstrates that visual cortex may retain functional organization after a partial subcortical visual pathway injury. This persistent conscious mapping suggests that disconnected visual cortex could serve as a region for interfacing with neural prosthetic devices for acquired blindness.
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OBJECTIVEElectrocorticography is an indispensable tool in identifying the epileptogenic zone in the presurgical evaluation of many epilepsy patients. Traditional electrocorticographic features (spikes, ictal onset changes, and recently high-frequency oscillations [HFOs]) rely on the presence of transient features that occur within or near epileptogenic cortex. Here the authors report on a novel corticography feature of epileptogenic cortex-covariation of high-gamma and beta frequency band power profiles. Band-limited power was measured from each recording site based on native physiological signal differences without relying on clinical ictal or interictal epileptogenic features. In this preliminary analysis, frequency windowed power correlation appears to be a specific marker of the epileptogenic zone. The authors' overall aim was to validate this observation with the location of the eventual resection and outcome.METHODSThe authors conducted a retrospective analysis of 13 adult patients who had undergone electrocorticography for surgical planning at their center. They quantified the correlation of high-gamma (70-200 Hz) and beta (12-18 Hz) band frequency power per electrode site during a cognitive task. They used a sliding window method to correlate the power of smoothed, Hilbert-transformed high-gamma and beta bands. They then compared positive and negative correlations between power in the high-gamma and beta bands in the setting of a hand versus a tongue motor task as well as within the resting state. Significant positive correlations were compared to surgically resected areas and outcomes based on reviewed records.RESULTSPositive high-gamma and beta correlations appeared to predict the area of eventual resection and, preliminarily, surgical outcome independent of spike detection. In general, patients with the best outcomes had well-localized positive correlations (high-gamma and beta activities) to areas of eventual resection, while those with poorer outcomes displayed more diffuse patterns.CONCLUSIONSData in this study suggest that positive high-gamma and beta correlations independent of any behavioral metric may have clinical applicability in surgical decision-making. Further studies are needed to evaluate the clinical potential of this methodology. Additional work is also needed to relate these results to other methods, such as HFO detection or connectivity with other cortical areas.