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Objective: Stereo‐electroencephalography (SEEG) is the preferred method for intracranial localization of the seizure‐onset zone (SOZ) in drug‐resistant focal epilepsy. Occasionally SEEG evaluation fails to confirm the pre‐implantation hypothesis. This leads to a decision tree regarding whether the addition of SEEG electrodes (two‐step SEEG – 2sSEEG) or placement of subdural electrodes (SDEs) after SEEG (SEEG2SDE) would help. There is a dearth of literature encompassing this scenario, and here we aimed to characterize outcomes following unplanned two‐step intracranial EEG (iEEG). Methods: All 225 adult SEEG cases over 8 years at our institution were reviewed to extract patient data and outcomes following a two‐step evaluation. Three raters independently quantified benefits of additional intracranial electrodes. The relationship between two‐step iEEG benefit and clinical outcome was then analyzed. Results: Fourteen patients underwent 2sSEEG and nine underwent SEEG2SDE. In the former cohort, the second SEEG procedure was performed for these reasons—precise localization of the SOZ (36%); defining margins of eloquent cortex (21%); and broadening coverage in the setting of non‐localizable seizure onsets (43% of cases). Sixty‐four percent of 2sSEEG cases were consistently deemed beneficial (Light's κ = 0.80). 2sSEEG performed for the first two indications was much more beneficial than when onsets were not localizable (100% vs 17%, p =.02). In the SEEG2SDE cohort, SDEs identified the SOZ and enabled delineation of margins relative to eloquent cortex in all cases. Significance: The two‐step iEEG is useful if the initial evaluation is broadly concordant with the original electroclinical hypothesis, where it can clarify onset zones or delineate safe surgical margins; however, it provides minimal benefit when the implantation hypothesis is erroneous, and we recommend that 2sSEEG not be generally utilized in such cases. SDE implantation after SEEG minimizes the need for SDEs and is helpful in delineating surgical boundaries relative to ictal‐onset zones and eloquent cortex. [ABSTRACT FROM AUTHOR]

ObjectiveThe RNS System is a direct brain-responsive neurostimulation system that is US Food and Drug Administration-approved for adults with medically intractable focal onset seizures based on safety and effectiveness data from controlled clinical trials. The purpose of this study was to retrospectively evaluate the real-world safety and effectiveness of the RNS System.MethodsEight comprehensive epilepsy centers conducted a chart review of patients treated with the RNS System for at least 1 year, in accordance with the indication for use. Data included device-related serious adverse events and the median percent change in disabling seizure frequency from baseline at years 1, 2, and 3 of treatment and at the most recent follow-up.ResultsOne hundred fifty patients met the criteria for analysis. The median reduction in seizures was 67% (interquartile range [IQR] = 33%-93%, n = 149) at 1 year, 75% (IQR = 50%-94%, n = 93) at 2 years, 82% (IQR = 50%-96%, n = 38) at ≥3 years, and 74% (IQR = 50%-96%, n = 150) at last follow-up (mean = 2.3 years). Thirty-five percent of patients had a ≥90% seizure frequency reduction, and 18% of patients reported being clinically seizure-free at last follow-up. Seizure frequency reductions were similar regardless of patient age, age at epilepsy onset, duration of epilepsy, seizure onset in mesial temporal or neocortical foci, magnetic resonance imaging findings, prior intracranial monitoring, prior epilepsy surgery, or prior vagus nerve stimulation treatment. The infection rate per procedure was 2.9% (6/150 patients); five of the six patients had an implant site infection, and one had osteomyelitis. Lead revisions were required in 2.7% (4/150), and 2.0% (3/150) of patients had a subdural hemorrhage, none of which had long-lasting neurological consequences.SignificanceIn this real-world experience, safety was similar and clinical seizure outcomes exceeded those of the prospective clinical trials, corroborating effectiveness of this therapy and suggesting that clinical experience has informed more effective programming.

We examined the efficacy of vagal nerve stimulation (VNS) for patients suffering from medically intractable epilepsy. Four randomized controlled trials (RCTs - 3 adult RCTs and 1 pediatric RCT) were identified in our comprehensive literature search. Across the 4 studies, high frequency VNS stimulation (frequency >20 Hz) consistently achieved a greater seizure frequency reduction (23.4-33.1%) relative to low frequency VNS stimulation (1 Hz,.6-15.2%). We identified 2 RCTs examining whether the parameters of stimulation influenced seizure control. These studies reported that VNS achieved seizure control comparable to those reported by the first 4 RCTs (22-43% seizure frequency reduction), irrespective of the parameters utilized for VNS stimulation. In terms of VNS associated morbidity, these morbidities were consistently higher in adults who underwent high frequency VNS stimulation (eg dysphonia 37-66%, dyspnea 6-25.3%). However, no such differences were observed in the pediatric population. Moreover, <2% of patients withdrew from the RCTs/prospective studies due to intolerable symptoms. To provide an assessment of how the risks and benefits of VNS impact the patient experience, 1 study assessed the well-being of enrolled patients (as a secondary end point) and found VNS was associated with an overall improvement in well-being. Consistent with this observation, we identified a prospective, non-randomized study that demonstrated improved quality of life for epilepsy patients managed with VNS and best medical practice relative to best medical practice alone. In aggregate, these RCT studies support the efficacy and benefit of VNS as a neuro-modulatory platform in the management of a subset of medically refractory epilepsy patients. [ABSTRACT FROM AUTHOR]

This review covers the broad topic of brain surgery in the treatment of pediatric intractable epilepsy. The authors review the latest advancements in the presurgical workup as well as the mandatory tests needed to explore the epilepsy workup in these children. They describe the different types of epilepsy from a surgical standpoint (temporal, extratemporal, multifocal, and hemispheric epilepsies) and various surgical procedures that can be proposed depending on the clinical scenario: lesionectomies, lobectomies, hemispherectomies, neuromodulation, and palliative surgeries. They also describe the key differences of the pediatric patient as compared with the adult patient in such pathologic conditions. [ABSTRACT FROM AUTHOR]

The objectives of this study were to determine the relationship between the severity of pathology and seizure outcomes in patients who underwent hemispherectomy for Rasmussen encephalitis (RE) and to investigate which clinical factors correlated with severity of pathology. In this retrospective cohort study, we collected and reviewed pathology and clinical variables. We ascertained seizure outcomes using Engel's classification, and Pardo stages were used to grade pathology. We included 29 unique patients who underwent 34 hemispherectomy procedures for analysis. There was no statistically significant correlation between Pardo stage and seizure outcome (P = 1). Increasing duration of epilepsy (β = 0.011, P = 0.02) and duration of hemiparesis (β = 0.024, P = 0.01) were significantly associated with a more severe Pardo stage. In contrast, the presence of epilepsia partialis continua had a negative relationship with Pardo stage (β = −0.49, P = 0.04). Twenty-six (89.75%) patients were Engel class I at the last follow-up, including all 5 patients who underwent redo hemispherectomy in our cohort. Consistent with the progressive nature of RE, more severe pathology was associated with a longer duration of epilepsy and longer duration of hemiparesis, while the presence of epilepsia partialis continua was associated with less severe pathology. Results from this series suggest the degree of cortical involvement with RE as assessed on surgical histopathology does not correlate with seizure outcome after hemispherectomy, which appears to be more dependent on surgical technique/complete disconnection. [ABSTRACT FROM AUTHOR]

Epilepsy is the most common form of chronic neurologic disease. Here, we review the available randomized controlled trials (RCTs) that examined the efficacy of resective epilepsy surgery in select patients suffering from medically intractable epilepsy (defined as persistent epilepsy despite two or more antiepileptic drugs [AEDs]). Three RCTs (two adult RCTs and one pediatric RCT) consistently supported the efficacy of resective surgery as treatment for epilepsy with semiology localized to the mesial temporal lobe. In these studies, 58–100% of the patients who underwent resective surgery achieved seizure freedom, in comparison to 0–13% of medically treated patients. In another RCT, the likelihood of seizure freedom after resective surgery was independent of the surgical approach (transSylvian [64%] versus subtemporal [62%]). Two other RCTs demonstrated that hippocampal resection is essential to optimize seizure control. But, no significant gain in seizure control was achieved beyond removing 2.5 cm of the hippocampus. Across RCTs, minor complications (deficit lasting < 3 months) and major complications (deficit > 3 months) ranged 2–5% and 5–11% respectively. However, nonincapacitating superior subquadrantic visual-field defects (not typically considered a minor or major complication) were noted in up to 55% of the surgical cohort. The available RCTs provide compelling support for resective surgery as a treatment for mesial temporal lobe epilepsy and offer insights toward optimal surgical strategy. [ABSTRACT FROM AUTHOR]

Purpose: Crossed cerebellar diaschisis (CCD) has been widely studied in hemispheric stroke but is less characterized in epilepsy. In this study, we used 18F-FDG PET/CT to investigate the risk factors for CCD and its prognostic value for intractable epilepsy caused by focal cortical dysplasia (FCD).Methods: One hundred medically intractable epilepsy patients pathologically diagnosed with FCD postoperatively were included and classified into two groups: CCD+ and CCD-. PET/CT images were analyzed qualitatively by visual assessment and semi-quantitatively using the absolute asymmetry index (|AI|). Clinical factors, including age, sex, body mass index (BMI), age at seizure onset, epilepsy duration, seizure type, seizure frequency, electroencephalography (EEG) and brain magnetic resonance imaging (MRI), were retrospectively assessed from medical records. Follow-up outcomes were evaluated according to the Engel classification at 3, 6, 12, 24 and 36 months postoperatively.Results: Of the 100 patients, 77 (77.0%) were classified as CCD-, and 23 (23.0%) were classified as CCD + . CCD+ patients had a higher number of lobes involved on PET (3.61 ± 2.16 vs 2.26 ± 1.01, P < 0.001) than CCD- patients. CCD- patients showed more negative MRI results than CCD + patients (P = 0.02). At 12 months postoperatively, 70.7% (29/41) of CCD- patients and 30.8% (4/13) of CCD + patients presented a favourable prognosis (P = 0.02). Significant differences in the average |AI| values in the posterior frontal and anterior temporal lobes were found between CCD+ and CCD- patients (P < 0.05).Conclusion: The number of lobes involved on PET, structural anomalies on MRI, the |AI| values in the posterior frontal and anterior temporal lobes may be predisposing factors for CCD. CCD occurrence may help predict the prognosis of FCD patients at 12 months postoperatively. [ABSTRACT FROM AUTHOR]

Kazuki Sakakura, Ayataka Fujimoto, Naoki Ichikawa, Keishiro Sato, Hideo Enoki, Tohru OkanishiComprehensive Epilepsy Center, Seirei Hamamatsu General Hospital, Hamamatsu JapanPurpose: Treatment options appear lacking for patients with epileptic seizure-induced shoulder dislocations who are not candidates for shoulder and focus resection surgeries. To reduce shoulder joint dislocations caused by epileptic seizures and simultaneously reduce the frequency and intensity of seizures, we performed corpus callosotomy for two patients with medically intractable epilepsy that induced repetitive shoulder joint dislocations.Materials and methods: A 21-year-old man (Patient 1) with bilateral temporal lobe epilepsy [Focal onset impaired awareness seizure (FIAS), 1/month; focal to bilateral tonic-clonic seizure (BTCS), 1/2–3 months], autism and intellectual disorder and a 34-year-old man (Patient 2) with left multi-lobar epilepsy (BTCS, 3–4/month; status epilepticus, 1/2–3 months), autism and intellectual disorder had suffered from repetitive seizure-induced shoulder dislocations (1/2–3 months for Patient 1; 3–4/month for Patient 2). Due to frequent seizures and uncooperativeness, they were not candidates for shoulder joint dislocation surgery. They were also not candidates for focus resection surgery due to multiple foci and uncooperativeness for invasive monitoring. We performed corpus callosotomy for both patients.Results: Postoperatively, frequencies of both shoulder dislocations (2 in 5 years of follow-up for Patient 1; 1 in 5 months of follow-up for Patient 2) and epileptic seizures were drastically reduced.Conclusions: For patients who are not candidates for focus resection and shoulder joint surgeries but who suffer from frequent shoulder joint dislocations, corpus callosotomy could be a treatment of last resort.Keywords: shoulder dislocation, corpus callosotomy, Bankart repair, Bristow procedure, medically intractable epilepsy

Purpose: For selected children with medically intractable epilepsy, hemispherectomy can be an excellent treatment option and its efficacy in achieving seizure freedom or reduction in seizure frequency has been shown in several studies, but patients' selection could not be straightforward and often it is taken on subjective basis. We described a multimodal approach to assess patient eligible for hemispherectomy and possibly predicting post-surgical outcomes. Methods: We describe pre- and post-surgical clinical features along with neuroradiological results by magnetic resonance imaging (MRI), functional magnetic resonance imaging (fMRI), MR-tractography (MRT), and neurophysiological study by single and paired pulses transcranial magnetic stimulation (TMS) in a child with cerebral palsy with epileptic encephalopathy, eligible for epilepsy surgery. Results: Presurgical TMS evaluation showed a lateralization of motor function on the left motor cortex for both arms, and results were confirmed by MRI studies. Interestingly, after surgery, both epilepsy and motor performances improved and TMS showed enhancement of intracortical inhibition and facilitation activity. Conclusion: Functional hemispherectomy is an effective treatment for drug-resistant epilepsy, and multimodal presurgical assessment may be a useful approach to guide surgeons in selecting patients. Moreover, pre- and post-surgical evaluation of these patients may enhance our understanding of brain plasticity phenomena. [ABSTRACT FROM AUTHOR]

Purpose: The recurrent seizures of pediatric drug-resistant epilepsy (DRE) are known to impair brain development and can lead to a loss in cognitive functioning. Surgery is increasingly being used to treat children with DRE. This study investigates the pre- and postoperative cognitive function in a pediatric epilepsy surgery cohort as well as predictive determinants of change in intelligence quotient (IQ) following surgery.Methods: A consecutive series of 91 Danish children who underwent focal resective epilepsy surgery between January 1996 and December 2016 were included. All underwent preoperative cognitive evaluation and were reevaluated at 1-year and/or 2-year follow-up. Single-operated and multi-operated patients were examined separately.Results: 79 of 91 patients were single-operated. Single-operated patients received less anti-epileptic drugs (AED) and experienced a decrease in seizure frequency postoperatively, p < 0.001. IQ increased postoperatively (IQ change ± standard deviation: 3.3 ± 14.0), p < 0.05. High preoperative seizure frequency was a significant predictor for decreased IQ, p < 0.01. Multi-operated patients did not experience a reduction in AED treatment. Surgery and continued AED treatment did, however, result in significantly better seizure control, p < 0.01. IQ remained unchanged in multi-operated patients.Conclusion: Epilepsy surgery allowed for IQ gains in single-operated patients. Preoperative seizure frequency was a significant predictor of IQ change following surgery. Interactions between other, not included, possible predictors remain to be examined. Single-operated patients had the best cognitive outcome. The inclusion of a non-surgical control group is needed to assess the extent of the beneficial effects of surgery on cognitive ability. [ABSTRACT FROM AUTHOR]

Background: Epilepsy in children negatively impacts on caregiver quality of life (QOL). The study aimed to evaluate the relationships between patient factors [demographics, clinical factors, health-related quality of life (HRQL)], contextual factors (socio-economic factors), caregiver mood, and caregiver QOL, and whether family factors mediate the relationship between patient HRQL and caregiver QOL.Methods: Children aged 4-18 years with medically intractable epilepsy were enrolled. Patient demographics, clinical data, patient HRQL [measured using Quality of Life in Childhood Epilepsy Questionnaire (QOLCE)], socio-economic factors, caregiver anxiety and depression, and family factors (adaptation, resources and demands) were assessed. Caregiver QOL was measured using CarerQol, which evaluates care-related QOL, incorporating the negative and positive effects of caregiving.Results: One hundred and eighty-one children were studied. In bivariable regression analysis, higher patient HRQL (QOLCE) (β = 0.54, p < 0.001) and household income (β = 10.49, p = 0.019) were associated with higher caregiver QOL. Higher depression (β = − 2.48, p < 0.001) and anxiety (β = − 2.04, p < 0.001) were associated with lower caregiver QOL. Seizure severity and other socio-economic factors did not influence caregiver QOL (all p > 0.05). In multivariable regression analysis, higher QOLCE (β = 0.21, p = 0.001), lower depression (β = − 1.07, p < 0.001) and lower anxiety (β = − 1.19, p < 0.001) were associated with higher caregiver QOL. Family demands and resources moderated the relationship between patient HRQL and caregiver QOL.Conclusions: Patient HRQL and caregiver mood were more important correlates of caregiver QOL than seizure severity in medically intractable epilepsy. The findings are significant in delineating variables (caregiver mood and family factors) that are potentially modifiable, and show promise for improving caregiver QOL. [ABSTRACT FROM AUTHOR]

Objective The objective of this study was to explore whether chronic electrocorticographic (ECoG) data recorded by a responsive neurostimulation system could be used to assess clinical responses to antiepileptic drugs (AEDs). Methods Antiepileptic drugs initiated and maintained for ≥ 3 months by patients participating in clinical trials of the RNS ® System were identified. Such “AED Starts” that produced an additional ≥ 50% reduction in patient-reported clinical seizure frequency were categorized as clinically beneficial, and the remaining as not beneficial. Electrocorticographic features recorded by the RNS ® Neurostimulator were analyzed during three periods: 3 months before the AED Start, first month after the AED Start, and the first 3 months after the AED Start. Results The most commonly added medications were clobazam (n = 41), lacosamide (n = 96), levetiracetam (n = 31), and pregabalin (n = 25). Across all four medications, there were sufficient clinical data for 193 AED Starts to be included in the analyses, and 59 AED Starts were considered clinically beneficial. The proportion of AED Starts that qualified as clinically beneficial was higher for clobazam (53.7%) and levetiracetam (51.6%) than for lacosamide (18.8%) and pregabalin (12%). Across all AED Starts for which RNS ECoG detection settings were held constant, the clinically beneficial AED Starts were associated with a significantly greater reduction in the detection of epileptiform activity (p < 0.001) at 1 (n = 33) and 3 months (n = 30) compared with AED Starts that were not beneficial at 1 (n = 71) and 3 months (n = 60). Furthermore, there was a significant reduction in interictal spike rate and spectral power (1–125 Hz) associated with a clinically beneficial response to an AED Start at 1 (n = 32) and 3 months (n = 35) (p < 0.001). These reductions were not observed at either 1 (n = 59) or 3 months (n = 60) for AED Starts that were not clinically beneficial. Conclusions Significant quantitative changes in ECoG data recorded by the RNS System were observed in patients who experienced an additional clinical response to a new AED. While there was variability across patients in the changes observed, the results suggest that quantitative ECoG data may provide useful information when assessing whether a patient may have a favorable clinical response to an AED. [ABSTRACT FROM AUTHOR]

Surgical treatment of focal epilepsy in the presence of periventricular nodular heterotopia (PVNH) poses a challenge, as the relative roles of the nodular tissue and the overlying cortex in the generation of seizures can be complex and variable. Here, we review the literature on chronic invasive EEG recordings in humans with this substrate and present two illustrative cases from our practice. We found that while inter-ictal spiking from nodules is common, clinical seizures rarely arise solely from nodular tissue. More typically, ictal onset is simultaneous with overlying neocortex or mesial temporal structures. Surgical outcome is more favorable in cases with unilateral (as opposed to bilateral) PVNH, and when a substantial or complete ablation of PVNH is performed. In rare cases, nodular ablation alone may be sufficient, as may be completed by MRI-guided laser interstitial thermal therapy. The mechanism(s) by which PNVH interacts with overlying cortex are not fully understood, but we suggest that PVNH either orchestrates or amplifies local network epileptogenicity. At present, invasive recordings with penetrating depth electrodes are required prior to surgical therapy, as illustrated in our cases. [ABSTRACT FROM AUTHOR]

• Brain-responsive neurostimulation reduces the frequency of disabling seizures. • Brain-responsive neurostimulation is well-tolerated and acceptably safe. • Quality of life and cognition improve with brain-responsive neurostimulation. • Chronic ambulatory electrocorticographic monitoring provides unprecedented insight. Controlled clinical trials in adults with medically intractable focal seizures treated with the RNS® System demonstrate that closed-loop responsive neurostimulation to the seizure focus reduces the frequency of disabling seizures, is well tolerated, and is acceptably safe. Seizure reductions begin with initiation of treatment and continue over time, reaching median reductions of 75% after 9 years of treatment. Treatment with responsive cortical stimulation is also associated with improvement in quality of life and cognitive function related to the functional area being treated. In addition, the RNS System's chronic ambulatory electrocorticographic monitoring provides unprecedented insight into each patient's disease management, and into the study of epilepsy itself, in ways that may enhance the treatment of epilepsy in the future. [ABSTRACT FROM AUTHOR]

Epilepsy is an important and common worldwide public health problem that affects people of all ages. A significant number of individuals with epilepsy will be intractable to medication. These individuals experience an elevated mortality rate and negative psychosocial consequences of recurrent seizures. Surgery of epilepsy is highly effective to stop seizures in well-selected individuals, and seizure freedom is the most desirable result of epilepsy treatment due to the positive improvements in psychosocial function and the elimination of excess mortality associated with intractable epilepsy. Globally, there is inadequate data to fully assess epilepsy-related quality of life and stigma, although the preponderance of information we have points to a significant negative impact on people with epilepsy (PWE) and families of PWE. This review of the psychosocial impact of epilepsy focuses on regions of Asia and Sub-Saharan Africa that have been analyzed with population study approaches to determine the prevalence of epilepsy, treatment gaps, as well as factors impacting psychosocial function of PWE and their families. This review additionally identifies models of care for medically intractable epilepsy that have potential to significantly improve psychosocial function.

Despite appropriate trials of at least two antiepileptic drugs, about a third of patients with epilepsy remain drug resistant (intractable; refractory). Epilepsy surgery offers a potential cure or significant improvement to those with focal onset drug-resistant seizures. Unfortunately, epilepsy surgery is still underutilized which might be in part because of the complexity of presurgical evaluation. This process includes classifying the seizure type, lateralizing and localizing the seizure onset focus (epileptogenic zone), confirming the safety of the prospective brain surgery in terms of potential neurocognitive deficits (language and memory functions), before devising a surgical plan. Each one of the above steps requires special tests. In this paper, we have reviewed the process of presurgical evaluation in patients with drug-resistant focal onset epilepsy.

Epilepsy can be a manifestation of paraneoplastic syndromes which are the consequence of an immune reaction to neuronal elements driven by an underlying malignancy affecting other organs and tissues. The antibodies commonly found in paraneoplastic encephalitis can be divided into two main groups depending on the target antigen: 1) antibodies against neuronal cell surface antigens, such as against neurotransmitter (N-methyl- d -aspartate (NMDA), alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA), gamma-aminobutyric acid (GABA)) receptors, ion channels (voltage-gated potassium channel (VGKC)), and channel-complex proteins (leucine rich, glioma inactivated-1 glycoprotein (LGI1) and contactin-associated protein-2 (CASPR2)) and 2) antibodies against intracellular neuronal antigens (Hu/antineuronal nuclear antibody-1 (ANNA-1), Ma2/Ta, glutamate decarboxylase 65 (GAD65), less frequently to CV2/collapsin response mediator protein 5 (CRMP5)). In this review, we provide a comprehensive survey of the current literature on paraneoplastic epilepsy indexed by the associated onconeuronal antibodies. While a range of seizure types can be seen with paraneoplastic syndromes, temporal lobe epilepsy is the most common because of the association with limbic encephalitis. Early treatment of the paraneoplastic syndrome with immune modulation/suppression may prevent the more serious potential consequences of paraneoplastic epilepsy. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the efficacy of chronic continuous hippocampal deep brain stimulation (DBS) in nonlesional refractory mesial temporal lobe epilepsy.Methods: Three adult patients with medically intractable epilepsy treated with hippocampal DBS were studied. Two patients underwent invasive recordings with depth stereo-electroencephalography (SEEG) electrodes to localize ictal onset zone prior to implantation of DBS electrodes. All the patients with no lesion in brain magnetic resonance imaging (MRI) scan received bilateral implantation of DBS electrodes. Chronic continuous high-frequency hippocampal stimulation was applied during treatment. The number of seizures in each patient before and after stimulation was compared.Results: Long-term hippocampal stimulation produced a median reduction in seizure frequency of 93%. Two out of these patients received unilateral activation of the electrodes and experienced a 95% and 92% reduction in seizure frequency after hippocampal DBS respectively. The last patient had bilateral electrode activation and had a seizure-frequency reduction of 91%. None of the patients had neuropsychological deterioration and showed side effects. Generalized tonic-clonic seizures disappeared completely after hippocampal DBS.Conclusions: Chronic continuous hippocampal DBS demonstrated a potential efficiency and safety in nonlesional refractory mesial temporal lobe epilepsy and might represent an effective therapeutic option for these patients. [ABSTRACT FROM AUTHOR]

Background: Regarding the complications of chronic intractable epilepsy, the presence of respectable lesions in many these patients that can be diagnosed with noninvasive sensitive techniques such as MRI and SPECT and the unrecognized significance of epilepsy surgery in our country, we have decided to review the management of medically intractable epilepsy in patients, who underwent epilepsy surgery in neurosurgery department of Loghman Hakim hospital between 1997-2003. Materials and Methods: In this study we retrospectively review 30 cases of medically intractable epilepsy that had underwent epilepsy surgery. All patients before surgery were investigated with brain MRI, brain SPECT, EEG and IQ test. Type of surgery was determined by MRI, SPECT and EEG findings. Pre - and postoperative seizure frequency and surgery complications studied. Seizure control was measured with Engel criteria. Results: Patients mean age was 22.4 years. Three cases (10%) were females that all underwent temporal mesial lobectomy. In 18 cases (60%) there were concordant brain lesion with seizure origin that 9 cases (30%) underwent mesial temporal lobectomy and remainder 9 cases (30%) underwent lesionectomy.other12 cases (40%) that have uncertain brain lesion but suffer from drop attack due to one or combination of atonic, tonic, tonic clonic, clonic, myoclonic, absence or clonic underwent anterior callosotomy. patients that underwent mesial temporal lobectomy, anterior callosotomy and lesionectomy were seizure-free in 77.7%, 58.3% and 55.5% of cases respectively. Conclusions: Provided to correct patient selection for epilepsy surgery we can manage intractable epilepsy properly. Regarding to the complication of intractable epilepsy, acceptable epilepsy surgery results and available sensitive noninvasive diagnostic techniques such as MRI in our country, epilepsy surgery should be considered seriously in our country and promoted.

The use of devices in the treatment of epilepsy is an emerging therapy for those patients whose seizures are not controlled by medications. This article will discuss current treatment options with devices for vagus nerve stimulation, deep brain stimulation and responsive neurostimulation. Emerging therapies in noninvasive neurostimulation such as with trigeminal nerve stimulation, transcranial magnetic stimulation and transcranial direct current stimulation may prove to be promising solutions. Finally, new and enhanced techniques of drug delivery are discussed as well as other devices with potential use in the study and treatment of epilepsy. [ABSTRACT FROM AUTHOR]

Objective This study aimed to investigate early predictors (6 months after diagnosis) of medical intractability in epilepsy. Methods All children < 12 years of age having two or more unprovoked seizures 24 h apart at Xinhua Hospital between 1992 and 2006 were included. Medical intractability was defined as failure, due to lack of seizure control, of more than 2 antiepileptic drugs at maximum tolerated doses, with an average of more than 1 seizure per month for 24 months and no more than 3 consecutive months of seizure freedom during this interval. Univariate and multivariate logistic regression models were performed to determine the risk factors for developing medical intractability. Receiver operating characteristic curve was applied to fit the best compounded predictive model. Results A total of 649 patients were identified, out of which 119 (18%) met the study definition of intractable epilepsy at 2 years after diagnosis, and the rate of intractable epilepsy in patients with idiopathic syndromes was 12%. Multivariate logistic regression analysis revealed that neurodevelopmental delay, symptomatic etiology, partial seizures, and more than 10 seizures before diagnosis were significant and independent risk factors for intractable epilepsy. The best model to predict medical intractability in epilepsy comprised neurological physical abnormality, age at onset of epilepsy under 1 year, more than 10 seizures before diagnosis, and partial epilepsy, and the area under receiver operating characteristic curve was 0.7797. This model also fitted best in patients with idiopathic syndromes. Conclusion A predictive model of medically intractable epilepsy composed of only four characteristics is established. This model is comparatively accurate and simple to apply clinically. [ABSTRACT FROM AUTHOR]

One of the most important steps in presurgical diagnosis of medically intractable epilepsy is to find the precise location of the epileptogenic foci. Electroencephalography (EEG) is a noninvasive tool commonly used at epilepsy surgery centers for presurgical diagnosis. In this paper, a modified particle swarm optimization (MPSO) method is used to solve the EEG source localization problem. The method is applied to noninvasive EEG recording of somatosensory evoked potentials (SEPs) for a healthy subject. A 1 mm hexahedra finite element volume conductor model of the subject's head was generated using T1-weighted magnetic resonance imaging data. Special consideration was made to accurately model the skull and cerebrospinal fluid. An exhaustive search pattern and the MPSO method were then applied to the peak of the averaged SEP data and both identified the same region of the somatosensory cortex as the location of the SEP source. A clinical expert independently identified the expected source location, further corroborating the source analysis methods. The MPSO converged to the global minima with significantly lower computational complexity compared to the exhaustive search method that required almost 3700 times more evaluations. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: Vagus nerve stimulation (VNS) therapy is a procedure to control seizure frequency in patients with medically intractable epilepsy. However, there is no data on efficacy in the subset of these patients with brain tumors. The purpose of this study is to evaluate the efficacy of VNS therapy in patients with brain tumor-associated medically intractable epilepsy. Methods: Data from the VNS therapy Patient Outcome Registry, maintained by the manufacturer of the device, Cyberonics Inc. (Houston, TX, USA), was queried to characterize the response of patients in whom a brain tumor was listed as the etiology of epilepsy. A case–control analysis was implemented and patient outcome was measured by Engel classification, median seizure response and responder rate (≥50% seizure reduction) using t-tests and chi-squared tests. Results: In 107 patients with an epilepsy etiology related to a brain tumor, seizure reduction was 45% at 3 months and 79% at 24 months with a responder rate of 48% at 3 months and 79% at 24 months. There was no statistical difference in seizure reduction compared with 326 case–control patients from the registry without brain tumors. There was no significant difference in anti-epileptic drug (AED) usage from baseline to 24 months post implant in either group. Conclusions: VNS therapy is equally effective in patients who suffer seizures secondary to brain tumors as in patients without history of a brain tumor. VNS therapy is a viable treatment option for patients with brain tumor associated medically intractable epilepsy, assuming cytoreductive and other adjuvant therapies have been fully explored. [Copyright &y& Elsevier]