Occurrence Of Postoperative Seizures Research Articles

Total posterior quadrant disconnection for drug-resistant epilepsy in children.

To assess seizure outcomes, prognostic factors, and developmental changes in children undergoing total posterior quadrant disconnection (PQD) for drug-resistant epilepsy (DRE). We conducted a retrospective analysis of the clinical data of children with DRE who underwent total PQD surgery. The study focused on Engel's classification for seizure outcomes, exploring correlation of preoperative data and surgical effectiveness, and predictors of seizure prognosis. It involved a comparative analysis of developmental levels pre- and 3 months postoperatively using Griffiths Mental Development Scales-China (GMDS-C), and the correlation between clinical characteristics and GMDS-C results. Out of 61 pediatric patients, 70.5% showed no seizure recurrence postoperatively. In the univariate analysis, interictal electroencephalogram (EEG), magnetic resonance imaging (MRI), fluorodeoxyglucose positron emission tomography (FDG-PET), and acute postoperative seizure (APOS) were significantly related to surgical prognosis. In multivariate analysis, interictal EEG and APOS were identified as predictors of seizure prognosis. Survival analysis indicated significant associations between MRI, interictal EEG, FDG-PET, APOS and postoperative seizure occurrence. Preoperative GMDS-C levels were significantly correlated with epilepsy duration, seizure frequency, interictal EEG, and FDG-PET. GMDS-C scores improved postoperatively, while developmental quotients remained stable. For patients with structural abnormalities in the entire posterior quadrant, thorough preoperative assessment and timely total PQD surgery can effectively control seizures without causing neurological development deterioration. APOS and interictal EEG abnormalities beyond the posterior quadrant are predictors for seizure prognosis but should not be deemed contraindications for surgery. Due to lack of analysis on pediatric total PQD cases, 61 pediatric patients who underwent total PQD surgery were retrospectively enrolled. Seizure and development results were collected and analyzed as dependent variables. The study found that 70.5% of patients were seizure-free and showed development improvement, with no deaths or severe complications reported. Prognosis predictors included APOS and interictal EEG abnormalities beyond the posterior quadrant.

Predictors for the Occurrence of Seizures in Meningioma.

Seizure is a common symptom of meningioma that has a major impact on patients' quality of life. The purpose of this study was to identify predictive factors for the occurrence of preoperative and postoperative seizures. The data of patients with resection of histologically confirmed meningioma at University Hospital Leipzig from 2009 to 2018 were retrospectively examined. Univariate and multivariate logistic regression analyses of different factors influencing seizure outcome were performed. The male gender was identified as an independent positive predictor for preoperative seizures (odds ratio [OR] 1.917 [95% confidence interval {CI} 1.044-3.521], p = 0.036), whereas headache (OR 0.230 [95% CI 0.091-0.582], p = 0.002) and neurological deficits (OR 0.223; [95% CI 0.121-0.410], p < 0.001) were demonstrated to be negative predictive factors. Sensorimotor deficit after surgery (OR 4.490 [95% CI 2.231-9.037], p < 0.001) was found to be a positive predictor for the occurrence of postoperative seizures. The identified predictors for the occurrence of seizures in meningioma can contribute to improving seizure treatment and patients' quality of life.

To Study Perioperative Changes in Plasma Phenytoin Levels in Patients with Brain Tumor Undergoing Craniotomy and Its Correlation with Postoperative Seizures

Abstract Introduction Phenytoin, although commonly used for postoperative seizure prophylaxis, exhibits variable results in mitigating seizure frequency following craniotomy. These discrepancies may be linked to a reduction in plasma phenytoin levels subsequent to the surgical intervention. Aims This prospective study aims to characterize changes in plasma phenytoin levels after craniotomy and their relationship with intraoperative blood loss. Methods Fifty consecutive patients were enrolled in this study after obtaining written informed consent. These patients had either been on oral phenytoin for at least 7 days or had received an intravenous loading dose before undergoing craniotomy. Serum phenytoin levels were measured 24 hours preoperatively, immediately before craniotomy (prior to skin incision), postcraniotomy (after skin closure), and 24 hours postcraniotomy. Additionally, intraoperative blood loss was calculated using a modified Gross formula. Results Immediately following craniotomy, there was a statistically significant mean decline of 28.16% in serum phenytoin levels. Furthermore, the analysis revealed a robust positive correlation between the decrease in phenytoin concentration level and several factors, including blood loss during surgery, the duration of the surgical procedure, intravenous fluids administered during surgery, and the occurrence of postoperative seizures. Conclusion This study underscores the potential utility of routinely measuring perioperative serum phenytoin levels in high-risk patients to prevent postcraniotomy seizures. Moreover, it suggests that patients with substantial intraoperative blood loss may benefit from an additional bolus dose of phenytoin toward the end of the surgical procedure.

Comparative Analysis of Single Versus Dual Anti-Epileptic Drugs for Controlling Intra-Operative and Early Postoperative Seizure in Glioma Patients Undergoing an Awake Craniotomy; A Retrospective Study

INTRODUCTION: Awake craniotomy (AC) is the standard approach for tumors of eloquent areas. However, concerns remain regarding the perioperative seizure risks and complications requiring general anesthesia (GA) or termination. METHODS: This retrospective cohort study included patients who underwent awake craniotomy for Glioma resection. Patients were divided into two groups based on their seizure control medication: Group S (N = 29) received one AED, while Group D (N = 26) received dual AEDs. We compared intraoperative seizures (IOS) and post-operative seizures (POS) rates between Groups S and D. Additionally, we evaluated the risk factors associated with POS and the 1-month post-operative Karnofsky Performance Scale (1M-KPS). RESULTS: This study considered a power of 0.9 so the effect size obtained was 0.866. 55 patients (41.8% female) with a median age of 39.0 (IQR 33.0-51.0) entered. The rate of IOS was 8 (27.6%) in Group S and 3 (11.5%) in Group D, with no statistically significant difference. (p = 0.137) POS occurred in 7 (24.1%) patients in group S and 2 (7.7%) patients in group D, (p = 0.100) pointing out no significant difference. The length of hospital stay (p = 0.606) and the length of ICU stay (p = 0.141), Post-op KPS, and 1M-KPS were not significantly different between the two cohorts (p = 0.131 and p = 0.217, respectively). The occurrence of POS was influenced neither by adjuvant therapy nor IDH1 mutation. The univariate and multivariate regression models showed pre-op KPS and the extent of resection had a significant effect on 1M-KPS. CONCLUSIONS: The addition of a second AED did not significantly affect POS prevention, IOS rate, or 1M-KPS improvement. Further research is needed for optimized strategies and improved patient outcomes.

P.137 Implementation of Canadian driving guidelines following cranial procedures: a systematic review and survey of Canadian neurosurgeons

Background: Following craniotomy, there is widespread agreement that post-operative neurological impairments require specialized evaluation to evaluate fitness to drive. However, for patients who had a craniotomy and do not have neurological deficits or known seizures, there is less consensus as to when return to driving is safe. In this study, we aim to review existing guidelines regarding driving post-craniotomy and assess the current practices for post-craniotomy recommendations in Canada. Methods: Our study has three components: 1) systematic review of existing guidelines for return to driving after cranial procedure; 2) review of primary evidence (cohort studies) regarding seizure risk following a craniotomy, depending of the underlying pathology; 3) online questionnaire distributed to Canadian neurosurgeons by the Canadian Neurosurgery Collaborative (CNRC) network. Results: Our systematic review unveiled various sets of guidelines for driving after a craniotomy. For instance, UK Driving and Vehicle Licensing Agency writes into law specific guidelines for return to driving varying based on underlying pathology. Their results were drawn from large cohort studies measuring the occurrence of post-operative seizures after craniotomy for a variety of conditions. The questionnaire is currently being distributed to Canadian neurosurgeons. Conclusions: Our study lays the first steps towards the development of Canadian guidelines for return to driving post-craniotomy.

Development of an integrated predictive model for postoperative glioma-related epilepsy using gene-signature and clinical data

BackgroundThis study aimed to develop an integrated model for predicting the occurrence of postoperative seizures in patients with diffuse high-grade gliomas (DHGGs) using clinical and RNA-seq data.MethodsPatients with DHGGs, who received prophylactic anti-epileptic drugs (AEDs) for three months following surgery, were enrolled into the study. The patients were assigned randomly into training (n = 166) and validation (n = 42) cohorts. Differentially expressed genes (DEGs) were identified based on preoperative glioma-related epilepsy (GRE) history. Least absolute shrinkage and selection operator (LASSO) logistic regression analysis was used to construct a predictive gene-signature for the occurrence of postoperative seizures. The final integrated prediction model was generated using the gene-signature and clinical data. Receiver operating characteristic analysis and calibration curve method were used to evaluate the accuracy of the gene-signature and prediction model using the training and validation cohorts.ResultsA seven-gene signature for predicting the occurrence of postoperative seizures was developed using LASSO logistic regression analysis of 623 DEGs. The gene-signature showed satisfactory predictive capacity in the training cohort [area under the curve (AUC) = 0.842] and validation cohort (AUC = 0.751). The final integrated prediction model included age, temporal lobe involvement, preoperative GRE history, and gene-signature-derived risk score. The AUCs of the integrated prediction model were 0.878 and 0.845 for the training and validation cohorts, respectively.ConclusionWe developed an integrated prediction model for the occurrence of postoperative seizures in patients with DHGG using clinical and RNA-Seq data. The findings of this study may contribute to the development of personalized management strategies for patients with DHGGs and improve our understanding of the mechanisms underlying GRE in these patients.

Seizure after surgical treatment of chronic subdural hematoma-Associated factors and effect on outcome.

IntroductionChronic subdural hematoma (cSDH) is becoming more prevalent due to population aging and the increasing use of antithrombotic drugs. Postoperative seizure in cSDH have a negative effect on outcome, and there currently no consensus regarding prophylactic anti-epileptic drug (AED) treatment. The objective of this study was to evaluate predisposing and triggering factors associated with postoperative epileptic seizure in patients with cSDH.MethodsAll patients, who were surgically treated for cSDH in a single tertiary care center between 2015 and 2019, were considered for inclusion. Relevant patient- and hematoma-specific characteristics were retrospectively extracted from hospital records. Paroxysmal events categorized by the treating physician as suspected postoperative seizures were noted. The clinical outcome was extracted from the last available follow-up visit and classified according to the Glasgow outcome scale (GOS).ResultsOf the included 349 patients, 54 (15.5%) developed suspected postoperative epileptic complications in the form of early seizure (≤ 7 days) in 11 patients (3.2%) and late seizure (>7 days) in 43 patients (12.3%). In the logistic regression analysis, solely depressed brain volume (supratentorial volume (ml) not filled with re-expanded brain) was independently associated with postoperative seizure (odds ratio [OR] 1.006, 95% CI: 1.001–1.011; p = 0.034). The occurrence of postoperative seizure (OR 6.210, 95% CI: 2.704–14.258; p < 0.001) and preoperative Markwalder grading (OR 2.919, 95% CI: 1.538–5.543; p = 0.001) were independently associated with unfavorable (GOS1−3) outcome.ConclusionLarger postoperative depressed brain volume was the only factor independently associated with suspected postoperative seizure, and it could help identify a subgroup of patients with higher susceptibility to epileptic events. Based on our data, no formal recommendation can be made regarding the prophylactic use of anti-epileptic drugs. Nevertheless, the relative safety of new generation AEDs and the detrimental effect of postoperative seizure on outcome may justify its use in a selected patient population.

381 Is Risk of Postoperative Seizures Higher in Patients with Blood Type a in Chronic Subdural Haematoma?

Abstract Introduction Seizure is a recognised complication of Chronic Subdural Haematoma (CSDH). Blood Type A has been indicated as a risk factor for developing postoperative seizures in Acute Subdural Haematoma (ASDH). However, to our knowledge there has not been a similar study to see if there is an association between blood type and seizure risk in CSDH. Method 699 patients who had a CSDH surgically evacuated with burr holes between 2013 and 2019 were identified and their electronic and paper notes were retrospectively reviewed. Clinical information including their blood type and occurrence of postoperative seizure were recorded. Results 26/699 patients overall had a postoperative seizure (3.7%). Blood type A had a higher overall number of seizures (4.3%, 13/301) than other blood types (3.4%,13/379) however this difference was not statistically significant (p = 0.22). Conclusions There is no convincing evidence that patients with blood type A have a higher risk of seizures after CSDH than patients with other blood types. Therefore, there is no reason to manage patients with blood type A differently regarding seizure prophylaxis.

New-Onset Postoperative Seizures in Patients With Diffuse Gliomas: A Risk Assessment Analysis.

Background: Glioma-related epilepsy (GRE) is the most common presenting sign of patients with diffuse glioma. According to clinical experience, new-onset postoperative seizures can be observed even in patients without preoperative GRE. The current study mainly aimed to explore the risk factors of new-onset postoperative seizures in those patients. In addition, the prognostic value of new-onset postoperative seizures was also discussed.Methods: Data of 313 patients without GRE were retrospectively reviewed. Chi-square test or Fisher's exact test were first performed to compare categorical variables between patients with new-onset postoperative seizures and those without. Subsequently, binary logistic regression analysis was conduct to further assess risk factors of new-onset postoperative seizures. Kaplan-Meier and Cox analysis were used to investigate the prognostic value of new-onset postoperative seizures for progression-free survival (PFS) and overall survival (OS).Results: Patients with low-grade tumors (p = 0.006), isocitrate dehydrogenase 1 (IDH1) mutation (p = 0.040) or low Ki-67 expression (p = 0.005) showed a higher incidence of new-onset postoperative seizures. IDH1 mutation was identified as the only independent predictor for new-onset postoperative seizures (OR, 2.075; 95% CI, 1.051–4.098; p = 0.035). Additionally, new-onset postoperative seizure occurrence was demonstrated as an independent predicter of prolonged OS (OR, 0.574; 95% CI, 0.335–0.983; p = 0.043), while younger age, gross total resection, low-grade and IDH1 mutation were independently correlated with prolonged OS and PFS.Conclusions: IDH1 mutation is an independent predictor for new-onset postoperative seizures in patients without preoperative GRE. Moreover, new-onset postoperative seizures can independently predict prolonged OS in those patients. The results of the current study can contribute to improving the individualized management of diffuse glioma.

Early and Late Postoperative Seizures in Meningioma Patients and Prediction by a Recent Scoring System.

Simple SummarySeizures are among the most common symptoms of meningioma patients even after surgery. This study sought to identify risk factors for early and late seizures in meningioma patients and to evaluate a modified version of a score to predict postoperative seizures on an independent cohort. The data underline that there are distinct factors identifying patients with a high risk of postoperative seizures following meningioma surgery which has been already shown before. We could further show that the high proportion of 43% of postoperative seizures occur as late seizures which are more dangerous because they may happen out of hospital. The modified STAMPE2 score could predict postoperative seizures when reaching very high scores but was not generally transferable to our independent cohort.Seizures are among the most common symptoms of meningioma. This retrospective study sought to identify risk factors for early and late seizures in meningioma patients and to evaluate a modified STAMPE2 score. In 556 patients who underwent meningioma surgery, we correlated different risk factors with the occurrence of postoperative seizures. A modified STAMPE2 score was applied. Risk factors for preoperative seizures were edema (p = 0.039) and temporal location (p = 0.038). For postoperative seizures preoperative tumor size (p < 0.001), sensomotory deficit (p = 0.004) and sphenoid wing location (p = 0.032) were independent risk factors. In terms of postoperative status epilepticus; sphenoid wing location (p = 0.022), tumor volume (p = 0.045) and preoperative seizures (p < 0.001) were independent risk factors. Postoperative seizures lead to a KPS deterioration and thus an impaired quality of life (p < 0.001). Late seizures occurred in 43% of patients with postoperative seizures. The small sub-cohort of patients (2.7%) with a STAMPE2 score of more than six points had a significantly increased risk for seizures (p < 0.001, total risk 70%). We concluded that besides distinct risk factors, high scores of the modified STAMPE2 score could estimate the risk of postoperative seizures. However, it seems not transferable to our cohort

Anticonvulsants for Preventing Seizures in Patients with Chronic Subdural Haematoma: Pilot Study

Introduction: There is increasing of the incidence of chronic subdural hematomas (CSDH), due to increase of the elderly population with increase of intake oral anticoagulation and antiplatelet drugs in this category of patients. Seizures occur as a complication in 2.3% to 20.4% of the patients. There is a considerable side effect associated with using of anti-epileptic drugs (AEDs). Aim of the Study: To rule the value of prophylactic antiepileptic drugs in prevention of seizures after surgical evacuation of chronic subdural hematoma. Methods: A prospective controlled non-randomized study was performed on 26 patients with chronic or subacute subdural hematoma that was surgically evacuated through burr-holes from April 2017 to June 2019. We divided the patients into 2 groups: group A patients received prophylactic antiepileptic drugs for 6 month and group B patients didn’t receive prophylactic antiepileptic drugs and the 2 groups were observed to detect occurrence of post-operative seizures for 6-month follow-up after surgery. Medical history, demographic data and imaging characteristics were recorded. Results: Seizure prevalence for all patients during hospitalization and 6-month follow-up was zero among the 13 patients who received prophylactic anti-seizure medications, and was 1 (7.7%) among the 13 patients who didn’t receive prophylactic anti-seizure medications. Conclusions: The incidence of post-operative seizures in patients with chronic subdural hematoma operated upon by burr holes evacuation is low. The administration of prophylactic antiepileptic drugs decreases the incidence of seizures after evacuation of CSDH, but the difference was not significant. So prophylactic antiepileptic drugs should not be routinely given for all patients with CSDH operated upon by burr hole evacuation unless there is risk factor for seizure development.

Preoperative tumor-associated epilepsy in patients with supratentorial meningioma: factors influencing seizure outcome after meningioma surgery.

Both pre- and postoperative seizures comprise common side effects that negatively impact patient quality of life in those suffering from intracranial meningioma. Therefore, seizure freedom represents an important outcome measure in meningioma surgery. In the current study the authors analyzed their institutional database to identify risk factors for postoperative seizure occurrence after surgical meningioma therapy in patients with preoperative symptomatic epilepsy. Between February 2009 and April 2017, 187 patients with preoperative seizures underwent resection of supratentorial meningioma at the authors' institution. Seizure outcome was assessed retrospectively 12 months after tumor resection according to the International League Against Epilepsy (ILAE) classification and stratified into favorable (ILAE class I) versus unfavorable (ILAE classes II-VI). A univariate and multivariate analysis was performed to identify factors influencing seizure outcome. Overall 169 (90%) of 187 patients with preoperative seizures achieved favorable outcome in terms of seizure freedom after meningioma resection. Multivariate analysis revealed peritumoral edema > 1 cm in maximal diameter and WHO grade II and III tumors, as well as a low extent of resection (Simpson grades III-V) as independent predictors for postoperative unfavorable seizure outcome. Surgery is highly effective in the treatment of seizures as common side effects of supratentorial meningioma. Furthermore, the present study identified several significant and independent risk factors for postoperative seizure occurrence, enabling one to select for high-risk patients that require special attention in clinical and surgical management.

Postcranioplasty seizures following decompressive craniectomy and seizure prophylaxis: a retrospective analysis at a single institution.

Cranioplasty is a relatively simple and less invasive intervention, but it is associated with a high incidence of postoperative seizures. The incidence of, and the risk factors for, such seizures and the effect of prophylactic antiepileptic drugs (AEDs) have not been well studied. The authors' aim was to evaluate the risk factors that predispose patients to postcranioplasty seizures and to examine the role of seizure prophylaxis in cranioplasty. The records of patients who had undergone cranioplasty at the authors' medical center between 2009 and 2014 with at last 2 years of follow-up were retrospectively reviewed. Demographic and clinical characteristics, the occurrence of postoperative seizures, and postoperative complications were analyzed. Among the 583 patients eligible for inclusion in the study, 247 had preexisting seizures or used AEDs before the cranioplasty and 336 had no seizures prior to cranioplasty. Of these 336 patients, 89 (26.5%) had new-onset seizures following cranioplasty. Prophylactic AEDs were administered to 56 patients for 1 week after cranioplasty. No early seizures occurred in these patients, and this finding was statistically significant (p = 0.012). Liver cirrhosis, intraoperative blood loss, and shunt-dependent hydrocephalus were risk factors for postcranioplasty seizures in the multivariable analysis. Cranioplasty is associated with a high incidence of postoperative seizures. The prophylactic use of AEDs can reduce the occurrence of early seizures.

Continuous EEG monitoring after brain tumor surgery

BackgroundProlonged seizures generate cerebral hypoxia and increased intracranial pressure, resulting in an increased risk of neurological deterioration, increased long-term morbidity, and shorter survival. Seizures should be recognized early and treated promptly.The aim of the study was to investigate the occurrence of postoperative seizures in patients undergoing craniotomy for primary brain tumors and to determine if non-convulsive seizures could explain some of the postoperative neurological deterioration that may occur after surgery.MethodsA single-center prospective study of 100 patients with suspected glioma. Participants were studied with EEG and video recording for at least 24 h after surgery.ResultsSeven patients (7%) displayed seizure activity on EEG recording within 24 h after surgery and another two patients (2%) developed late seizures. One of the patients with early seizures also developed late seizures. In five patients (5%), there were non-convulsive seizures. Four of these patients had a combination of clinically overt and non-convulsive seizures and in one patient, all seizures were non-convulsive. The non-convulsive seizures accounted for the majority of total seizure time in those patients. Non-convulsive seizures could not explain six cases of unexpected postoperative neurological deterioration. Postoperative ischemic lesions were more common in patients with early postoperative seizures.ConclusionsEarly seizures, including non-convulsive, occurred in 7% of our patients. Within this group, non-convulsive seizure activity had longer durations than clinically overt seizures, but only 1% of patients had exclusively non-convulsive seizures. Seizures were not associated with unexpected neurological deterioration.

Prophylactic antiepileptic treatment with levetiracetam for patients undergoing supratentorial brain tumor surgery: a two-center matched cohort study.

Guidelines on the administration of prophylactic antiepileptic drugs (AED), and specifically levetiracetam, for brain tumor surgery are still lacking. In this two-center matched cohort study, we aim to compare the proportion of postoperative seizures during follow-up after supratentorial tumor surgery in patients receiving no seizure prophylaxis, and those treated with levetiracetam perioperatively. Three hundred sixteen consecutive patients undergoing supratentorial tumor surgery, without history of seizures were included: 207 patients did not receive AED (no AED group), and 109 patients received levetiracetam perioperatively (levetiracetam group). The primary outcome measure was the rate of postoperative seizures. Additionally, uni- and multivariate analyses assessing possible risk factors for postoperative seizures were performed. No statistically significant difference for the occurrence of postoperative seizures was found between the two groups (10.1%, n = 21 in the no AED group vs. 9.2%, n = 10, in the levetiracetam group; p = 0.69, OR 0.9 [0.4-2.0), NNT 103 [12.9-17.1]). After propensity score matching, the primary outcome was observed in 13 patients (12.4%) from the no AED group and in 9 patients (8.6%) from the levetiracetam group (p = 0.50, OR 0.7 [0.3-1.6], NNT 26.3 [8.3-22.4]). Among all analyzed possible risk factors for postoperative seizures, only postoperative infarction showed a statistically significant association with higher seizure rates in multivariate analysis (OR 8.2 [1.1-60.6], p = 0.04). Prophylactic treatment with levetiracetam after brain tumor surgery showed no statistically significant effect in preventing postoperative seizures. However, in case a postoperative infarction occurs, its administration might be indicated.

Prophylactic Levetiracetam for Seizure Control After Cranioplasty: A Multicenter Prospective Controlled Study

To study efficacy and safety of prophylactic levetiracetam (LEV) administration in adults undergoing cranioplasty. We prospectively enrolled and randomly divided 200 adults undergoing cranioplasty into 2 groups: LEV (prophylactic LEV for 24 weeks) and control (no prophylactic antiepileptic drugs). Demographic and clinical characteristics; occurrence of postoperative seizure; changes in IQ, memory quotient, and activities of daily living scores; and postoperative side effects during hospital stay were analyzed at 2-, 24-, and 48-week follow-up visits. Significant differences were found between groups in both early-stage seizures in the initial 2 weeks and late-stage seizures in the 3-24 weeks after cranioplasty (P < 0.05). Postoperative seizures occurred in 17.0% in the control group and 4.1% in the LEV group 48 weeks after cranioplasty, which was found to be significant (P=0.0020). Patients with abnormal preoperative or postoperative electroencephalography (EEG) with spikes or sharp waves presented with an increased number of postoperative seizures compared with patients with normal EEG readings at 48 weeks. Significant differences were found between patients with postoperative seizures and patients without postoperative seizures in regard to changes in IQ, memory quotient, activities of daily living, and patient satisfaction scores (P < 0.01). No significant difference was found in side effects between the 2 groups. Postoperative seizure is a common complication of cranioplasty, especially in patients with preoperative or postoperative abnormal EEG with spikes or sharp waves. Prophylactic LEV administration significantly reduced postcranioplasty seizures during LEV usage and had few side effects.

Risk Factors of Preoperative and Early Postoperative Seizures in Patients with Meningioma: A Retrospective Single-Center Cohort Study

Well-defined risk factors for the identification of patients with meningioma who might benefit from preoperative or early postoperative seizure prophylaxis are unknown. We investigated and quantified risk factors to determine individual risks of seizure occurrence in patients with meningioma. A total of 634 adult patients with meningioma were included in this retrospective cohort study. Patient gender and age, tumor location, grade and volume, usage of antiepileptic drugs (AEDs) and extent of resection were determined. Preoperative and early postoperative seizures occurred in 15% (n= 97) and 5% (n= 21) of the patients, respectively. Overall, 502 and 418 patients were eligible for multivariate logistic regression analyses of preoperative and early postoperative seizures, respectively. Male gender (odds ratio [OR], 2.06; P= 0.009), a non-skull base location (OR, 4.43; P < 0.001), and a tumor volume of >8 cm3 (OR, 3.05; P= 0.002) were associated with a higher risk of preoperative seizures and were used to stratify the patients into 3 prognostic groups. The high-risk subgroup of patients with meningioma showed a seizure rate of >40% (OR, 9.8; P< 0.001). Only a non-skull base tumor location (OR, 2.61; P= 0.046) was identified as a significant risk factor for early postoperative seizures. AEDs did not reduce early postoperative seizure occurrence. Seizure prophylaxis might be considered for patients at high risk of developing seizures who are for other reasons being considered for watchful waiting instead of resection. In contrast, our data do not provide any evidence of the efficacy of perioperative AEDs in patients with meningioma.

SM-02 * LEVETIRACETAM USAGE IN POST-OPERATIVE SEIZURE MANAGEMENT IN MALIGNANT GLIOMA

BACKGROUND: There is a lack of consensus in the use of newer-generation anti-epileptic drugs (AEDs) as prophylaxis in patients with malignant glioma (MG) who undergo surgical resection. The rate of seizure occurrence in MG is less than low-grade gliomas, but due to the debilitating nature of seizures, clinicians routinely prescribe prophylactic AEDs. Recommendations were last published in 2000 by the American Academy of Neurology based on research of older generation AEDs. Levetiracetam (LEV) is a newer generation AED with an improved safety profile and proven efficacy in heterogeneous patient populations, but its efficacy has yet to be determined in MG patients. METHODS: A retrospective analysis of AED usage was conducted among 114 patients diagnosed with MG (WHO Grade III-IV) who underwent initial resection at a single institution during 2011-2012. Demographics, comorbidities, tumor and surgical characteristics, AED usage, toxicity and seizure occurrence were reviewed. Seizure history was characterized prior to and up to 6 months after surgery. Logistic regression was used to evaluate the association of LEV prophylaxis and other risk factors with post-operative seizure occurrence. RESULTS: Patients were male (58%), had a gross total resection (88%), a history of seizures (44%), and received LEV pre-operatively (45%). Post-operatively, 91% received LEV of which 25% experienced a seizure. Side effects of LEV use were rare (n = 10, 10%), and included irritability, somnolence, psychiatric disturbances, and thrombocytopenia. Patient's age was a significant predictor of seizure occurrence. Older patients had a higher risk of seizure in the 6 months post-operatively (OR = 2.6, 95% CI 1.10-6.35, p = 0.0327). CONCLUSIONS: LEV is well tolerated in MG patients undergoing resection. Older age is associated with post-operative seizure occurrence. Future studies need to assess the effectiveness of LEV in reducing post-operative seizure recurrence in this population in comparison to other AEDs.

Adolescents with tetralogy of Fallot: neuropsychological assessment and structural brain imaging

Few data are available on the neuropsychological, behavioural, or structural brain imaging outcomes in adolescents who underwent corrective surgery in infancy for tetralogy of Fallot. In this single-centre cross-sectional study, we enrolled 91 adolescents (13-16 years old) with tetralogy of Fallot and 87 referent subjects. Assessments included tests of academic achievement, memory, executive functions, visual-spatial skills, attention, and social cognition, as well as brain magnetic resonance imaging. Genetic abnormalities or syndromes were present in 25% of tetralogy of Fallot patients, who had markedly greater neuropsychological morbidities than did patients without a syndrome. However, even patients without a syndrome performed significantly worse than the referent group or population norms in all of the neuropsychological domains assessed. In multivariable regression in those without a genetic/phenotypic syndrome, the strongest predictors of adverse late neurodevelopmental outcomes included a greater number of complications at the first operation, more total surgical complications across all operations, and occurrence of post-operative seizures. The presence of at least one abnormality on structural magnetic resonance imaging was more frequent in tetralogy of Fallot patients than the referent group (42% versus 8%). Adolescents with tetralogy of Fallot are at increased neurodevelopmental risk and would benefit from ongoing surveillance and educational supports even after childhood.

Early and late postoperative seizure outcome in 97 patients with supratentorial meningioma and preoperative seizures: a retrospective study

We identified factors associated with early and late postoperative seizure control in patients with supratentorial meningioma plus preoperative seizures. In this retrospective study, univariate analysis and multivariate logistic regression analysis compared 24 clinical variables according to the occurrence of early (≤1 week) or late (>1 week) postoperative seizures. Sixty-two of 97 patients (63.9 %) were seizure free for the entire postoperative follow-up period (29.5 ± 11.8 months), while 13 patients (13.4 %) still had frequent seizures at the end of follow-up. Fourteen of 97 patients (14.4 %) experienced early postoperative seizures, and emergence of new postoperative neurological deficits was the only significant risk factor (odds ratio = 7.377). Thirty-three patients (34.0 %) experienced late postoperative seizures at some time during follow-up, including 12 of 14 patients with early postoperative seizures. Associated risk factors for late postoperative seizures included tumor progression (odds ratio = 7.012) and new permanent postoperative neurological deficits (odds ratio = 4.327). Occurrence of postoperative seizures in patients with supratentorial meningioma and preoperative seizure was associated with new postoperative neurological deficits. Reduced cerebral or vascular injury during surgery may lead to fewer postoperative neurological deficits and better seizure outcome.