Significance of seizure in cerebral venous sinus thrombosis

PurposeTo report the frequency and predictors of presenting seizures in cerebral venous sinus thrombosis (CVST) and their influence on seizure recurrence and outcome.MethodsThis retrospective study, between 1995 and 2011, included 90 consecutive patients with CVST diagnosed using magnetic resonance imaging (MRI) and magnetic resonance venography (MRV). Clinical parameters like frequency, type (presenting, early, and late), and duration of seizures, precipitating causes of CVST, and underlying prothrombotic conditions, were recorded. The location of infarction on MRI and the number of sinuses involved on MRV, were noted. The patients were prescribed anticoagulants, and those with seizures were prescribed antiepileptic drugs. The patients were followed up at 3, 6, and 12 months. The functional outcome at 6 months was categorized into death, poor, partial and complete recovery.ResultsA total of 42 patients with CVST presented with seizures (focal 11, focal with secondary generalized 19, and generalized tonic clonic 16), of whom 10 had status epilepticus. On univariate analysis, supratentorial lesion (P = 0.005), frontal (P = 0.02) or parietal lobe (P = 0.04) involvement and haemorrhagic lesion (P = 0.002) were associated with higher risk of presenting seizure. On multivariate analysis, only supratentorial parenchymal lesion on MRI (odds ratio [OR] = 4.67, 95% confidence interval [CI] 1.51–15.08, P = 0.005) was independently associated with higher risk of presenting seizure. Only 4 patients had early seizures and none had late seizures. At 6 months, 10 patients died and 73 patients had complete recovery. Seizures were not associated with death (P = 1.00) and 6-month functional outcome (P = 0.66).ConclusionAbout half the patients with CVST had presenting seizures which was independently related to supratentorial lesion. However, seizures were not related to death or 6-month outcome.     

Ki-67 overexpression in WHO grade II gliomas is associated with poor postoperative seizure control

PurposeSeizures are the most common initial symptom in patients with low-grade gliomas, and approximately 30% of these patients still suffer from epilepsy after gross-total resection of the tumour. We examined the relationship between the overexpression of ki-67 in WHO grade II gliomas and seizure control.MethodsA series of 93 histologically confirmed WHO grade II glioma tissues were analysed through immunohistochemical staining for ki-67 expression. Follow-up visits regarding seizure control were scheduled at 12 months. The Engel classification was used to categorise patients’ seizure status.ResultsOf the 93 patients analysed, 65 (66.3%) patients initially presented with seizures. A total of 36 patients were diagnosed with WHO grade II oligodendrogliomas, 29 patients had oligoastrocytomas and 28 patients had astrocytomas. Ki-67 was over-expressed in 15 patients. One year after surgery poor seizure control was observed in 11 of these patients. In contrast, low ki-67 expression (<10%) was found in 78 patients. Poor seizure control was observed in 36 patients (difference between ki-67 over- and low expression groups P = 0.002). Logistic regression analysis revealed that patients with gross-total resection achieved better seizure control while ki-67 overexpression and age below 38 years were poor seizure control factors explained of the variance of seizure outcome (OR: 0.382, 4.354 and 1.822, respectively).ConclusionsIn WHO grade II gliomas, Ki-67 is a molecular marker which predicts poor seizure control of glioma patients after the resection of the tumour. Gross-total resection, ki-67 overexpression and age below 38 years significantly affect seizure prognosis.     

Circadian patterns of generalized tonic-clonic evolutions in pediatric epilepsy patients

ObjectiveTo investigate the sleep/wake, day/night, and 24-h periodicity of pediatric evolution to generalized tonic–clonic seizures (GTC).MethodsCharts of 407 consecutive patients aged 0–21 years undergoing continuous video-EEG monitoring for epilepsy were reviewed for the presence of GTC evolution. Seizures were characterized according to 2001 ILAE terminology. Charts were reviewed for EEG seizure localization, MRI lesion, and for seizure occurrence in 3-h time blocks, out of sleep or wakefulness, and during the day (6 AM–6 PM) or night. Analysis was done with binomial testing. Regression models were fitted using generalized estimating equations with patients as the cluster level variable.Results71 patients (32 girls, mean age 12.63 ± 5.3 years) had 223 seizures with GTC evolution. Sleep/wake seizure distribution predicted tonic–clonic evolution better than time of day, with more occurring during sleep (p < 0.001). Tonic–clonic evolution occurred most frequently between 12–3 AM and 6–9 AM (p < 0.05). Patients with generalized EEG onset had more tonic–clonic evolution between 9 AM and 12 PM (p < 0.05). Patients with extratemporal focal seizures were more likely to evolve during sleep (p < 0.001); this pattern was not found in patients with temporal or generalized seizure onset on EEG. Patients without MRI lesions were more likely to evolve between 12 AM and 3 AM (p < 0.05), in the sleeping state (p < 0.001), and at night (p < 0.05). Logistic regression revealed that sleep and older patient age were the most important predictors of GTC evolution.ConclusionGTC evolution occurs most frequently out of sleep and in older patients. Our results may assist in seizure prediction, individualized treatment patterns, and potentially complication and SUDEP prevention.     

Seizure frequency in children with epilepsy: Factors influencing accuracy and parental awareness

RationaleThe objective of this study was to ascertain the accuracy of clinical reports to determine the seizure frequency in children diagnosed with epilepsy.MethodsWe reviewed the clinical record of 78 children (January–May of 2006) admitted to the EEG–video monitoring with epilepsy diagnosis. Clinical reports of parents and the files of EEG–video monitoring were reviewed to determine parents’ awareness for seizures.ResultsDuring video–EEG monitoring, 1244 were recorded on 78 children. Seizures were confirmed in 1095 of which 472 were correctly reported (38%) by parents whereas 623 remained under-reported (50%). Parents’ report thus had a sensitivity of 43%, positive predictive value of 76% to identify seizures. Based on the EEG–video monitoring, seizures were reported accurately in 22 (28%) and under-reported in 38 (49%) children. In the under-reported group, none of the seizures were recognized in 10 (13%), only a portion identified in 28 children. The parents’ report describing seizure frequency has limited value for young children (p = 0.01) and children with absence seizures (p = 0.03). However, clinical reports were accurate for the children with developmental delay (p < 0.06) or not being on any anticonvulsant drug (AED) therapy (p = 0.02).ConclusionOur results indicate that a significant number of seizures remain under-reported by parents of children with epilepsy. The current study underscores that the seizure frequency should be interpreted with caution for young children and children with absence seizures. Video–EEG recording has a complimentary role to the clinical observation for the accurate assessment of seizure frequency in children.     

IDH1/2 mutations in WHO grade II astrocytomas associated with localization and seizure as the initial symptom

IntroductionSeizures are the most common initial symptom in patients with low-grade glioma and their occurrence strongly depends on the tumor location. The majority of low-grade gliomas reveal mutations in the genes encoding isocitrate-dehydrogenase 1 (IDH1) or 2 (IDH2). These mutations are associated with metabolic changes that are potentially epileptogenic. We investigated the correlation between IDH1/2 mutations and tumor localization and seizure as the initial symptom.Materials and methodsThis retrospective study included patients with a diagnosis of WHO grade II astrocytoma and cortical infiltration and in whom initial symptoms were documented and biopsy tissue was available for IDH1/2 analysis. IDH1/2 mutation analysis was performed by direct sequencing or by immunohistochemistry with an antibody which detects mutated protein IDH1 R132H. Sequencing was carried out if immunohistochemistry was negative. IDH1/2 status was defined as mutated if either of these investigations were positive.ResultsSeventy-nine patients were included. IDH1 or IDH2 mutation was present in 63 (80%) patients who on average were younger than patients without IDH1/2 mutation (40 vs. 47 years, p = 0.0331, t-test). IDH1/2 mutations were associated with frontal tumor location (p = 0.0202). All 12 tumors in the insula revealed IDH1/2 mutations. Seizure as the initial symptom was recorded in 57 (72%) patients and was associated with IDH1 or IDH2 mutation by multivariate analysis (OR 22.563, p = 0.0019).ConclusionIn WHO grade II astrocytomas, IDH1/2 mutations mostly occur in tumors infiltrating the frontal lobe. Seizure as the initial symptom is associated with IDH1 or IDH2 mutation.     

Cerebrospinal fluid tau as a marker of neuronal damage after epileptic seizure

PurposeWhether repeated brief seizures can cause neuronal damage is controversial. Cerebrospinal fluid (CSF) total tau (T-tau) and phosphorylated tau (P-tau) measurements have been suggested for the diagnosis of Alzheimer's disease, and T-tau may also be a marker of axonal damage and neuronal degeneration. We studied T-tau and P-tau levels and P-tau/T-tau ratio in CSF after epileptic seizures in order to determine whether they are increased after seizures.MethodsA total of 54 patients with tonic–clonic or partial secondarily generalized seizures due to various etiologies were studied and CSF obtained within 48 h after the seizure.ResultsThere were no statistical differences in the levels of T-tau (p = 0.09, ANOVA) or P-tau (p = 0.60) between different etiologic groups or controls. No patients with epilepsy of unknown origin had abnormal CSF T-tau whereas 11 patients with acute or remote symptomatic seizures had abnormal T-tau levels and the P-tau/T-tau ratio showed significant differences between the groups and controls (p = 0.003).ConclusionsEpileptic seizures with unknown etiology did not increase CSF tau levels. Abnormal tau levels were associated with either acute or remote symptomatic seizures with known etiology. The presence of elevated CSF tau increases the probability of symptomatic cause in a patient with a seizure.     

IDH1 and IDH2 mutations in postoperative diffuse glioma-associated epilepsy

ObjectiveIsocitrate dehydrogenase 1 and 2 mutations (IDH1/2) have an established association with preoperative seizures in patients with grades II–IV diffuse gliomas. Here, we examined if IDH1/2 mutations are a biomarker of postoperative seizure frequency.MethodsThis was a retrospective study. Patients with grades II–IV supratentorial diffuse glioma, immunohistochemistry results of IDH1-R132H, and antiepileptic drug (AED) prescribed postoperatively were included. The primary outcome was seizure frequency over the first 12 postoperative months: Group A — postoperative seizure freedom; Group B — 1–11 seizures over 12 months (less than one seizure per month); and Group C — greater than one seizure per month. Rates of IDH1-R132H mutation were compared between the three outcome groups in univariate and multivariate analyses. Subgroup analysis was performed in 64 patients with IDH1/2 pyrosequencing data.ResultsOne hundred cases were included in the analysis: 30.0% grade II, 20.0% grade III, and 50.0% grade IV gliomas. Group B patients averaged 1 seizure over 12 months, compared with 2 seizures per month in Group C. Isocitrate dehydrogense 1-R132H mutation was present in 29.3% (17/58) of Group A, 18.2% (14/22) of Group B, and 70.0% (14/20) of Group C patients (p = 0.001). On multivariate analysis, after controlling for preoperative seizure, grade, and temporal tumor location, IDH1-R132H was associated with Group C when compared with both Group A (RR 4.75, p = 0.032) and Group B (RR 9.70, p = 0.012). In the subgroup with IDH1/2 molecular data, an IDH1/2 mutation was present in 64.7% (22/34) of Group A, 28.6% (4/14) of Group C, and 87.5% (14/16) of Group C patients (p = 0.004).SignificanceIn patients with supratentorial diffuse gliomas, IDH1-R132H mutations are associated with a more severe phenotype of postoperative epilepsy. These findings support further research into IDH mutations, and the potential for an antiepileptic therapeutic effect of their inhibitors, in patients with glioma-associated epilepsy.     

Detecting health disparities among Caucasians and African-Americans with epilepsy

ObjectiveThe aim of the study was to determine whether African-Americans and Caucasians who receive care at a tertiary epilepsy center can be distinguished on a variety of demographic, clinical, and psychosocial variables.MethodsWe surveyed 111 consecutive patients followed at a tertiary epilepsy center.ResultsOn univariate analysis, African-Americans had significantly more seizures (P = 0.03), lower scores on the Beliefs About Medicines Questionnaire—Specific (Necessity minus Concerns) (BMQ-S) (P = 0.01), and higher scores on the BMQ—General (BMQ-G) (P = 0.02). In binary logistic regression with race as the target variable, higher seizure frequency remained significantly associated with being African-American (P = 0.04). After ordinal regression with seizure frequency as the target variable, being African-American (P = 0.04) and higher BMQ-G scores (P = 0.02) remained significantly associated with increased seizure frequency.ConclusionCompared with Caucasians, African-Americans have higher seizure frequency and scores on the BMQ indicating a higher mistrust of medications. Aside from race, attitudes toward medications are also independently associated with seizure control.     

Sleep before and after temporal lobe epilepsy surgery

PurposePatients with epilepsy often complain of non-restorative sleep. This is the consequence of the acute effect of seizures and the chronic effect of epilepsy responsible for disrupting sleep architecture. Other factors such as antiepileptic drugs (AEDs), also play a role in the alteration of sleep organization. The aim of this study was to evaluate the specific effect of seizures and interictal epileptiform abnormalities (IEAs) on sleep, in particular to see whether reducing seizure frequency by epilepsy surgery might improve sleep organization in these patients.MethodsEleven patients with refractory mesial temporal lobe epilepsy, who underwent surgical treatment and who were seizure free at the follow-up, were included in the study. Treatment with AEDs was not significantly modified before the second year of follow-up. Patients were evaluated before surgery, at 1-year and 2-year follow-up visits with a videoEEG monitoring (24 h/24). At each follow-up visit, interictal epileptiform abnormalities and sleep macrostructure parameters were assessed.ResultsAll patients showed a reduction of their IEAs. At 1-year follow-up, total sleep time and REM sleep increased significantly (p = 0.032 and p = 0.006, respectively). At 2-year follow-up, an important increase of REM sleep was observed (p = 0.028). Most significant variations were noted 1 year after surgery. No significant variations were observed between the first and the second year after surgery.ConclusionsSurgical treatment of temporal lobe epilepsy may improve sleep macrostructure by reducing the number of seizures and of IEAs. These results indirectly confirm the role of epilepsy in disrupting sleep organization chronically.     

Acute postoperative seizures and long-term outcome following pediatric epilepsy surgery

PurposeAcute post-operative seizures (APOS) after epilepsy surgery, previously believed to be benign, are increasingly associated with poor long-term prognosis. Prior literature has focused primarily on adult temporal lobe epilepsy. This retrospective study aimed to identify the prevalence, prognostic significance and risk factors for APOS in pediatric epilepsy surgery at a single center.MethodRetrospective chart review of all children aged 0–21 years undergoing resective surgery for epilepsy between 2009 and 2012 at a single center. APOS were defined as seizures within 30 days of resection. Surgical outcome was determined, using a minimum of 12 months postoperative follow-up for inclusion.ResultsAPOS, defined as a seizure within 30 days of resection, were identified in 50/112 (44%) of patients. APOS were a significant predictor of poor postoperative seizure outcome (ILAE 4–6); only 26% of those with APOS had a good outcome (ILAE 1–3), compared to 76% without APOS. Timing of postoperative seizure was not correlated with outcome. Most (54%) with APOS and good outcome had continued seizures between 14-30 days postoperatively. Patients with APOS after temporal (p = 0.05) and extratemporal (p < 0.001) resections had a significantly worse prognosis. APOS after hemispherectomy were not associated with a worse prognosis (p = 0.22). Key risk factors for APOS include lack of ictal EEG lateralization to operated hemisphere/side of MRI abnormality.ConclusionThis study shows an association between APOS and poor outcome in both temporal and extratemporal pediatric epilepsy surgery. Findings support the expansion of APOS duration to 30 days.     

Is elevated pre-ictal heart rate associated with secondary generalization in partial epilepsy?

BackgroundPeople with epilepsy are at risk for sudden unexpected death. Cardiac arrhythmia is one possible mechanism. We have studied seizure-related changes in cardiac rhythm.MethodsVideo-EEG and ECG from 38 patients with epileptic seizures during long-term monitoring for investigation of partial epilepsy with ictal impairment of consciousness were obtained. Seizures were classified as either complex partial or secondarily generalized. Inter-ictal, pre-ictal, ictal and post-ictal heart rate was calculated for the first recorded seizure.ResultsHeart rate during the pre-ictal period was higher (p = 0.016) in patients with secondarily generalized seizures (n = 11) compared to patients with complex partial seizures (n = 27). Heart rate was also elevated during and after generalized seizures (p < 0.015). Inter-ictal heart rate was not different in patients with secondary generalization compared to patients with partial seizures.ConclusionWe report elevated heart rate prior to partial seizure onset in those attacks which become secondarily generalized compared to seizures which remain localized. The finding may be relevant for the understanding of sudden death in epilepsy.     

Comparison between febrile and afebrile seizures associated with mild rotavirus gastroenteritis

PurposeWe aimed on identifying the differences of febrile and afebrile seizures associated with mild rotavirus gastroenteritis (RVGE) in the pediatric population.MethodMedical charts of pediatric patients who had been admitted between July 1999 and June 2011 due to RVGE were retrospectively reviewed. Subjects were ultimately divided into three groups; ‘no seizure’ (NS: patients without seizure), ‘febrile seizure’ (FS: patients with fever during seizure), ‘afebrile seizure’ (AFS: patients without fever during seizure). Comparisons between groups were carried out on demographic and clinical characteristics, laboratory test results, electroencephalogram findings, brain magnetic resonance imaging findings, antiepileptic treatment, and prognosis.ResultsAmong the 755 subjects who had been admitted due to mild rotavirus enteritis, 696 (90.3%) did not have any seizures, 17 (2.2%) had febrile seizures, 42 (5.5%) had afebrile seizures. The duration of gastrointestinal symptoms before the onset of seizures were significantly shorter in the FS group compared to the AFS group (1.3 ± 0.8 vs. 2.8 ± 1.0 days; p < 0.0001). A single seizure attack was significantly higher in the AFS group (3.0 ± 1.6 vs. 1.7 ± 1.0 episodes; p = 0.0003), and the frequency of seizures that were of focal type with or without secondary generalization were significantly higher in the AFS group (33.3% vs. 6.0%; p = 0.0139). All patients among the FS and AFS group had not received further antiepileptic treatment after discharge, and none developed epilepsy during follow up period.ConclusionDespite some differences in seizure characteristics, both febrile and afebrile seizures associated with mild RVGE were mostly benign with a favorable prognosis.     

Seizures during intracarotid methohexital and amobarbital testing

BackgroundMethohexital and amobarbital have been used as agents for Wada testing in the presurgical evaluation of patients with epilepsy. Previous experience with methohexital as an anesthetic indicates that methohexital may decrease seizure threshold and may trigger seizures.MethodsA retrospective chart review of 760 intracarotid amobarbital and methohexital tests was performed to determine the frequency of seizures associated with preoperative intracarotid barbiturate testing for language and memory lateralization.ResultsSixteen patients (2.1%) who had seizures were found. In 3 patients, seizures occurred prior to barbiturate injection, and in 13, following barbiturate injection. After injection of amobarbital, 4 of 538 patients (0.7%) had a seizure. Nine of 222 patients had a seizure after methohexital injection (4.1%) (P = 0.001).ConclusionPatients with a previous history of epilepsy may be at higher risk for seizures after methohexital injection as compared with amobarbital injection.     

Major depressive disorder as a predictor of a worse seizure outcome one year after surgery in patients with temporal lobe epilepsy and mesial temporal sclerosis

PurposeThe association between pre-surgical psychiatric disorders (PDs) and worse seizure outcome in patients with refractory epilepsy submitted to surgery has been increasingly recognized in the literature. The present study aimed to verify the impact of pre- and post-surgical PD on seizure outcome in a series of patients with refractory temporal lobe epilepsy and mesial temporal sclerosis (TLE–MTS).MethodData from 115 TLE–MTS patients (65 females; 56.5%) who underwent cortico-amygdalohippocampectomy (CAH) were analyzed. Pre- and post-surgical psychiatric evaluations were performed using DSM-IV and ILAE criteria. The outcome subcategory Engel IA was considered as corresponding to a favorable prognosis. A multivariate logistic regression model was applied to identify possible risk factors associated with a worse seizure outcome.ResultsPre-surgical PDs, particularly major depressive disorder (MDD), anxiety and psychotic disorders, were common, being found in 47 patients (40.8%). Fifty-six patients (48.7%) were classified as having achieved an Engel IA one year after CAH. According to the logistic regression model, the presence of pre-surgical MDD (OR = 5.23; p = 0.003) appeared as the most important risk factor associated with a non-favorable seizure outcome.ConclusionAlthough epilepsy surgery may be the best treatment option for patients with refractory TLE–MTS, our findings emphasize the importance of performing a detailed psychiatric examination as part of the pre-surgical evaluation protocol.     

Fever as a seizure precipitant factor in Panayiotopoulos syndrome: a clinical and genetic study

PurposeTo examine fever as a precipitating factor for focal seizures in patients with Panayiotopoulos syndrome (PS) and evaluate the role of SCN1A in PS patients with seizures triggered by fever.MethodsFrom January 2000 to June 2008, we identified patients referred for seizures who fulfilled the criteria of PS. Patients were divided into two groups, according to the presence (group A) or the absence (group B) of seizures triggered by fever. Electroclinical features of the two groups were compared. In addition, an analysis of SCN1A in patients of group A was performed.ResultsThirty patients fulfilled the inclusion criteria. Eleven patients (36%) had at least one focal autonomic seizure triggered by fever (group A). In group A, 7/11 patients (63.5%) had the first focal autonomic seizure during a febrile illness. Two of these 7 patients were misdiagnosed at the onset of PS. The median age at the onset of PS was slightly lower in group A than in group B (p = .050). Moreover, patients in group A more frequently had a positive familial history of febrile seizures (FS) (p = .047). No mutations of SCN1A were found in any of the 10 patients screened.ConclusionFever is a common trigger for focal autonomic seizures in PS. Knowing that an autonomic manifestation during fever can be an epileptic seizure could facilitate diagnosis and prevent unnecessary investigations and erroneous treatments. Moreover, our data show that SCN1A gene does not contribute significantly to susceptibility to autonomic seizures during fever in patients with PS.     

Safety of video-EEG monitoring and surgical outcome in patients with mesial temporal sclerosis and psychosis of epilepsy

PurposeCortico-amygdalohippocampectomy (CAH) has become an important treatment option for patients with refractory temporal lobe epilepsy and mesial temporal sclerosis (TLE-MTS); it has resulted in a 60–70% seizure remission rate and significant quality of life (QOL) improvements. Video-electroencephalography (VEEG) monitoring has been widely used in epilepsy centers for pre-surgical evaluation. A major concern in epilepsy surgery is whether to consider CAH treatment in patients with psychosis of epilepsy (POE). This study analyzed the safety and adverse events (AEs) of VEEG monitoring and the post-surgical outcomes of patients with refractory TLE-MTS and POE who underwent CAH.MethodClinical, sociodemographic and VEEG data from 18 patients with TLE-MTS and POE were analyzed. Psychiatric evaluations were performed using DSM-IV and ILAE criteria. The seizure outcome was evaluated using Engel's criteria.ResultsTwo patients (11.2%) presented AEs that did not result in increased lengths of hospitalization. Of the 10 patients (55.5%) who underwent CAH, 6 (60%) became free of disabling seizures (Engel I). The psychiatric and QOL evaluations revealed improvements of psychotic symptoms (p = 0.01) and in Physical Health (p = 0.01) following surgery.ConclusionThese data reinforce that VEEG monitoring is a safe method to evaluate patients with refractory TLE-MTS and POE in epilepsy centers.     

Clinical heterogeneity of juvenile myoclonic epilepsy: Follow-up after an interval of more than 20 years

PurposeThe view that juvenile myoclonic epilepsy (JME) is a uniform and life-long disorder is currently being challenged. The aim of this study was to assess the seizure and psychosocial outcome of JME at least 20 years after onset.MethodsIn 1992, 42 patients with JME were identified. In 2012, 37 agreed to a semi-structured interview. In the remaining five, only medical records were available.ResultsOf 40 patients with known seizure outcome, 21 were in remission for >5 years. Seven were off antiepileptic drugs (AEDs), four being seizure free for >10 years. Myoclonic seizures (MC) evolving to generalized tonic–clonic seizures (GTC) were associated with seizure persistence (p = 0.013), whereas >1 year between MC and GTC onset was associated with a trend to GTC remission (p = 0.069). Of 19 patients with uncontrolled seizures, eight experienced remission with second generation AEDs.Favorable psychosocial outcome by interview was found in a third, whereas another third had psychiatric comorbidity, seven with substance or alcohol abuse. Psychosocial and seizure outcome did not correlate.ConclusionThis study corroborates the heterogeneity of JME in terms of seizure and psychosocial outcome, but without a clear association between the two. It confirms that seizure control may persist after AED withdrawal in some and supports MC evolving to GTC as a predictor of seizure persistence. Moreover, it suggests that newer broad spectrum AEDs may improve the prognosis of JME; their impact should be focus of prospective studies.     

Is reoperation an option for patients with temporal lobe epilepsy after failure of surgery?

PurposeEpilepsy surgery is the most efficacious therapeutic modality for patients with medically refractory focal epilepsies, but surgical failures remain a challenge to the epilepsy treatment team. The aim of present study was to evaluate the postoperative outcome of patients who underwent reoperation after a failed epilepsy surgery on the temporal lobe.MethodsWe systematically analyzed the results of comprehensive preoperative evaluations before the first surgery, and before and after reoperation in 17 patients with drug resistant temporal lobe epilepsies.ResultsOverall, 13 of 17 patients (76.5%) improved after reoperation: five patients (29.4%) were completely seizure free after reoperation (median duration 60 months, range 12–72); six patients (35.3%) were seizure free at least 12 month before observation points (median duration 120.5 months, range 35–155) and two patients (11.8%) had a decrease in seizure frequency. Four patients (23.5%) remained unchanged with respect to seizure frequency and severity. There was no correlation between the improvement in seizure outcome after reoperation and other clinical data except of the history of traumatic brain injury (TBI). The patients who had no history of TBI improved after reoperation, compared to patients with TBI (p = 0.044). The postoperative seizure outcome of patients with incongruent Video-EEG results before the first surgery (p = 0.116) and before reoperation (p = 0.622) was not poorer compared to patients with congruent Video-EEG results.ConclusionsReoperation can considerably improve the operative outcome of the first failed epilepsy surgery in patients with drug resistant temporal lobe epilepsies. Epilepsy centres should be encouraged to report the results of failed epilepsy surgeries.     

Bimodal ultradian seizure periodicity in human mesial temporal lobe epilepsy

BackgroundMesial temporal lobe epilepsy (mTLE) has been suggested to follow a circadian rhythm. Previous research found an afternoon peak in mTLE seizure occurrence. We evaluated the pattern of seizure occurrence in patients with well-localized mTLE and hypothesized that peak seizure frequency would occur in the afternoon, and that this pattern would not be altered by age, gender, or seizure focus.MethodsWe retrospectively identified consecutive mTLE patients with a seizure-free outcome following anterior temporal lobectomy from 1993 to 2004 with video-EEG captured seizures. We recorded and plotted the 24-h clock time for each seizure and performed cosinor analysis. SAS Proc GLIMMIX was used to fit the linearized transform of the cosinor model. Negative binomial regression fitted by the generalized estimating equations (GEE) method was also performed to estimate and compare the mean seizure rates over a 24-h day.ResultsSixty mTLE patients monitored between 2 and 16 days were analyzed. Mean (standard deviation), median number of seizures per subject were 10.47(7.86), 9.00. Cosinor plots indicated that the function had two modes: 7–8 a.m. and 4–5 p.m. GEE analysis was consistent with peak seizure frequency occurrence at 6–8 a.m. (p < 0.0001) and 3–5 p.m. (p < 0.01).ConclusionsWe found a bimodal pattern of seizure occurrence in human mTLE, with peak seizure frequencies occurring between 6–8 a.m. and 3–5 p.m. confirming an afternoon peak, as well as a previously unsuspected morning peak in seizure occurrence that provides rationale for future investigations of antiepileptic drug chronopharmacology and informs patient counseling regarding patterns of seizure occurrence.     

Clinical relevance of source location in frontal lobe epilepsy and prediction of postoperative long-term outcome

PurposeTo evaluate the value of magnetoencephalography (MEG) source localization in localization of epileptic activities and predicting surgical outcome in frontal lobe epilepsies (FLE).MethodsForty-six patients with presurgical MEG evaluation and intractable FLE surgery (28 male patients) were analyzed retrospectively with a mean follow-up of 5 years. Dipole analysis was performed for MEG source imaging (MSI). The localization of dipole clusters in relation to the dominant hemisphere, lesions, resection cavity and functional cortex were analyzed. The predictive value of MSI in respect to clinical outcome with long-term postoperative follow up was evaluated.ResultsInterictal focal epileptic activities were found in 82.6% (38/46) patients with monofocal activity 81.6% (31/38) and multifocal activities 18.4% (7/38). Seizure free rate was 47.9% at the mean follow-up of 5.0 ± 4.0 years (median 11.5, range 2–57). Seizure recurrence mainly occurred in the first 1 year after surgery. In the monofocal epileptic activity group, 58.1% (18/31) of the patients were seizure free, predicitng postoperative seizure freedom better than multifocal localization 0% (0/7) (p = 0.028). Dipole clusters were completely resected in 70.9% of monofocal activity patients, which had higher seizure free rates compared to partial resection (p = 0.002). In patients with surgery in the dominant hemisphere, seizure control was less likely (p = 0.006).ConclusionMSI contributes to the clinical prediction of postoperative outcome in FLE patients. MSI may non-invasively disclose early epileptogenic lesions, pointing to a resectable lesion, and it then facilitates shortcut route of presurgical evaluation.