Seizures as a presenting symptom in neurosurgical patients: A retrospective single-institution analysis

Malignant Glioma

This chapter provides a comprehensive overview of malignant gliomas, the most common primary brain tumor in adults. These tumors are varied in their cellular origin, genetic profile, and morphology under the microscope, but together they share some of the most dismal prognoses of all neoplasms in the body. Although there is currently no cure for malignant glioma, persistent efforts to improve outcomes in patients with these tumors have led to modest increases in survival, and researchers worldwide continue to strive toward a deeper understanding of the factors that influence glioma development and response to treatment. In addition to well-established epidemiology, clinical manifestations, and common histopathologic and radiologic features of malignant gliomas, this section considers recent advances in molecular biology that have led to a more nuanced understanding of the genetic changes that characterize the different types of malignant glioma, as well as their implications for treatment. Beyond the traditional classification of malignant gliomas based on histopathological features, this chapter incorporates the World Health Organization's 2016 criteria for the classification of brain tumors, with special focus on disease-defining genetic alterations and newly established subcategories of malignant glioma that were previously unidentifiable based on microscopic examination alone. Traditional therapeutic modalities that form the cornerstone of treatment for malignant glioma, such as aggressive surgical resection followed by adjuvant chemotherapy and radiation therapy, and the studies that support their efficacy are reviewed in detail. This provides a foundation for additional discussion of novel therapeutic methods such as immunotherapy and convection-enhanced delivery, as well as new techniques for enhancing extent of resection such as fluorescence-guided surgery.

Meningioma Related Epilepsy- Pathophysiology, Pre/postoperative Seizures Predicators and Treatment

Meningiomas are the most common primary brain tumors accounting for about 30% of all brain tumors. The vast majority of meningiomas are slow-growing and of benign histopathology rendering them curable by surgery alone. Symptomatic lesions depend on the location with signs of mass effect or neurological deficits. Seizures are the presenting symptoms in approximately 30% of cases, which negatively affect quality of life, limit independence, impair cognitive functioning, as well as increase the risk for psychiatric comorbidities including depression. Although surgical resection may offer seizure freedom in 60-90% of meningiomas, seizures persist after surgical resection in approximately 12-19% of patients. Anti-seizure medications (ASMs) are employed in management, however, are limited by adverse neurocognitive side-effects and inefficacy in some patients. The potential predictors of pre- and post-operative seizures in meningioma patients have been identified in the literature. Understanding various factors associated with seizure likelihood in meningioma patients can help guide more effective seizure control and allow for better determination of risk before and after surgery.

Brain tumor-related epilepsy and risk factors for metastatic brain tumors: analysis of 601 consecutive cases providing real-world data

OBJECTIVE

It is necessary to accurately characterize the epidemiology and trends of brain tumor-related epilepsy (BTE) in patients with metastatic brain tumors. This study aimed to determine the incidence of BTE associated with metastatic brain tumors and retrospectively investigate the risk factors for BTE.

METHODS

This retrospective analysis included 601 of 631 consecutive patients with metastatic brain tumors who received treatment, including surgery, radiotherapy, and/or other treatments. BTE and the clinical course were examined retrospectively. Logistic regression multivariate analyses were performed to identify risk factors for BTE.

RESULTS

BTE was reported in 148 (24.6%) of 601 patients during the entire course. Of these 148 patients, 81 (54.7%) had first-onset epilepsy (13.5% of all patients). Of the 520 cases of nonepileptic onset, 53 were in the prophylactic antiepileptic drug (AED) group. However, 12 of these patients and 55 of the no-prophylactic AED group developed epilepsy during the course of the study. Including these 67 patients, 148 patients were examined as the group of all epilepsy cases during the entire course. In 3 patients, the seizure progressed to status epilepticus. In most patients, the BTE (n = 83, 56.1%) manifested as focal aware seizures. Logistic regression analysis identified young age (p = 0.037), male sex (p = 0.026), breast cancer (p = 0.001), eloquent area (p < 0.001), peritumoral edema (p < 0.001), dissemination (p = 0.013), and maximum tumor volume (p = 0.021) as significant risk factors for BTE. BTE was more common with tumor volumes greater than the cutoff value of 1.92 ml.

CONCLUSIONS

BTE appears to be more likely to occur in cases with young age, male sex, breast cancer, tumors involving eloquent areas, brain edema, dissemination, and giant tumors.

DIagnostic Subdural EEG electrodes And Subdural hEmatoma (DISEASE): a study protocol for a prospective nonrandomized controlled trial

Background

Epileptic seizures are common clinical features in patients with acute subdural hematoma (aSDH); however, diagnostic feasibility and therapeutic monitoring remain limited. Surface electroencephalography (EEG) is the major diagnostic tool for the detection of seizures but it might be not sensitive enough to detect all subclinical or nonconvulsive seizures or status epilepticus. Therefore, we have planned a clinical trial to evaluate a novel treatment modality by perioperatively implanting subdural EEG electrodes to diagnose seizures; we will then treat the seizures under therapeutic monitoring and analyze the clinical benefit.

Methods

In a prospective nonrandomized trial, we aim to include 110 patients with aSDH. Only patients undergoing surgical removal of aSDH will be included; one arm will be treated according to the guidelines of the Brain Trauma Foundation, while the other arm will additionally receive a subdural grid electrode. The study’s primary outcome is the comparison of incidence of seizures and time-to-seizure between the interventional and control arms. Invasive therapeutic monitoring will guide treatment with antiseizure drugs (ASDs). The secondary outcome will be the functional outcome for both groups as assessed via the Glasgow Outcome Scale and modified Rankin Scale both at discharge and during 6 months of follow-up. The tertiary outcome will be the evaluation of chronic epilepsy within 2–4 years of follow-up.

Discussion

The implantation of a subdural EEG grid electrode in patients with aSDH is expected to be effective in diagnosing seizures in a timely manner, facilitating treatment with ASDs and monitoring of treatment success. Moreover, the occurrence of epileptiform discharges prior to the manifestation of seizure patterns could be evaluated in order to identify high-risk patients who might benefit from prophylactic treatment with ASDs.

Trial registration

ClinicalTrials.gov identifier no. NCT04211233.

Epilepsy and aging

The intersection of epilepsy and aging has broad, significant implications. Substantial increases in seizures occur both in the elderly population, who are at a higher risk of developing new-onset epilepsy, and in those with chronic epilepsy who become aged. There are notable gaps in our understanding of aging and epilepsy at the basic and practical levels, which have important consequences. We are in the early stages of understanding the complex relationships between epilepsy and other age-related brain diseases such as stroke, dementia, traumatic brain injury (TBI), and cancer. Furthermore, the clinician must recognize that the presentation and treatment of epilepsy in the elderly are different from those of younger populations. Given the developing awareness of the problem and the capabilities of contemporary, multidisciplinary approaches to advance understanding about the biology of aging and epilepsy, it is reasonable to expect that we will unravel some of the intricacies of epilepsy in the elderly; it is also reasonable to expect that these gains will lead to further improvements in our understanding and treatment of epilepsy for all age groups.

Epileptic Syndrome and Cranioplasty: Implication of Reconstructions in the Electroencephalogram

BACKGROUND

In the presence of a skull deformity after large decompressive craniectomy (DC), neurologic deterioration manifesting as epileptic syndrome (ES) may occur independently of the primary disease or spontaneous improvement may be unduly impaired, and these unfavorable outcomes have sometimes been reversed by cranioplasty. The objective of this study was to analyze the influence of cranioplasty on the presence of ES in patients who underwent DC.

METHODS

A prospective study was performed from October 2016 to October 2017 involving patients who underwent DC and subsequent cranioplasty. Electroencephalographic (EEG) status before and after cranioplasty was analyzed in the presence of seizures and was compared with results after DC.

RESULTS

The sample included 52 patients. Male sex (78.8%) and traumatic brain injury (82.7%) were common indications for DC. ES after DC was verified in 26.9% of patients, and 50% of patients presented with abnormal EEG status. ES after cranioplasty was noted in 21.2% and 36.3% of patients followed by abnormal EEG status. All patients with precranioplasty epileptogenic paroxysms showed better EEG tracings after the procedure.

CONCLUSIONS

In routine clinical practice, altered amplitudes were observed in the region of bone defects. Although cranioplasty reduced pathologic EEG status (epileptogenic paroxysms), it was not able to produce new EEG tracings that could predict changes in seizure discharge or reduce ES.

Seizures in meningioma

More than one-third of patients with meningiomas will experience seizures at some point in their disease. Despite this, meningioma-associated epilepsy remains significantly understudied, as most investigations focus on tumor progression, extent of resection, and survival. Due to the impact of epilepsy on the patient's quality of life, identifying predictors of preoperative seizures and postoperative seizure freedom is critical. In this chapter, we review previously reported rates and predictors of seizures in meningioma and discuss surgical and medical treatment options. Preoperative epilepsy occurs in approximately 30% of meningioma patients with peritumoral edema on neuroimaging being one of the most significant predictor of seizures. Other associated factors include age <18, male gender, the absence of headache, and non-skull base tumor location. Following tumor resection, approximately 70% of individuals with preoperative epilepsy achieve seizure freedom. Variables associated with persistent seizures include a history of preoperative epilepsy, peritumoral edema, skull base tumor location, tumor progression, and epileptiform discharges on postoperative electroencephalogram. In addition, after surgery, approximately 10% of meningioma patients without preoperative epilepsy experience new seizures. Variables associated with new postoperative seizures include tumor progression, prior radiation exposure, and gross total tumor resection. Both pre- and postoperative meningioma-related seizures are often responsive to antiepileptic drugs (AEDs), although AED prophylaxis in the absence of seizures is not recommended. AED selection is based on current guidelines for treating focal seizures with additional considerations including efficacy in tumor-related epilepsy, toxicities, and potential drug-drug interactions. Continued investigation into medical and surgical strategies for preventing and alleviating epilepsy in meningioma is warranted.

Seizure and status epilepticus in chronic subdural hematoma

BACKGROUND

Acute symptomatic seizure (ASz) and status epilepticus (SE) are serious conditions associated with poor quality of life, with unfavorable psychosocial and functional outcome. Chronic subdural hematoma (cSDH) is a common neurosurgical disease related to those complications; therefore, we aimed to evaluate incidence, predictors of ASz/SE, and outcome in this cohort.

METHODS

We retrospectively analyzed patient diagnosed cSDH between 2010 and 2017. Beside their incidence of ASz/SE, patient characteristics, symptoms at admission, comorbidities, and all previously published relevant parameters were assessed. Recurrence rate and functional outcome were analyzed at hospital discharge and 90-day follow-up.

RESULTS

A total of 375 patients were included; incidence of ASz was 15.2% and of SE, 1.9%. In the univariate analysis, drainage insertion (P =  0.004; OR = 0.3) was a significant negative predictor for ASz/SE and multivariate analysis, including all significant parameters, designated GCS ≤13 at admission (P = 0.09; OR = 1.9), remote stroke (P = 0.009; OR = 2.9), and recurrence rate within 14 days (P = 0.001; OR = 3.3; with an incidence of 13%) as independent predictors for ASz/SE. Overall, patients with ASz/SE had significantly unfavorable outcome at discharge (54.7%; P < 0.001) and follow-up (39.5%; P < 0.001) with only slight improvement. Late seizures occurred in 3.8% within follow-up period. Any patient with SE had an unfavorable outcome at discharge without any improvement at follow-up having a mortality rate of 14.2%.

CONCLUSION

Independent predictors for ASz/SE are GCS ≤13 at admission, remote stroke, and recurrent hematoma in patients with cSDH, which is associated with worse functional outcome, particularly those with SE. Due to the higher rate of seizures than recurrence rate, a routine pre- and postoperative EEG besides CT is recommended.

Risk factors for preoperative and late postoperative seizures in primary supratentorial meningiomas

OBJECTIVE

We performed a retrospective study to identify factors associated with preoperative and late postoperative seizures in primary supratentorial meningiomas.

PATIENTS AND METHODS

Between July 2003 and December 2014, we extracted 303 consecutive patients who underwent primary resection for supratentorial meningiomas at a single institution. Univariate analysis and multivariate logistic regression analysis were performed to determine the associations of seizure occurrence and outcome.

RESULTS

Forty-nine (16.2%) of the total 303 patients presented with preoperative seizures. The risk factors independently associated with preoperative seizures were vasogenic edema (OR 4.44, p = 0.001), parasagittal or parafalcine location (OR 2.20, p = 0.020), and absence of neurologic deficit (OR 0.30, p = 0.003). Among these patients, 33 (67.3%) were seizure free postoperatively (Engel Class I). Of the 303 patients, we observed late postoperative seizures in 35 (11.6%) patients. The associated risk factors included history of preoperative seizure (OR 3.96, p = 0.002), bigger tumor size (OR 1.04, p = 0.002), and continuation of anti-epileptic drugs (OR 4.74, p = 0.001). We analyzed that meningiomas with a largest diameter of greater than 45.5 mm were 4.2 times more likely to have late postoperative seizures than those with less diameter (HR 4.20, p < 0.001). Ten (28.6%) of the 35 patients with late postoperative seizures experienced poor seizure control. The independently associated predictive factors were high grade meningiomas (WHO Grade II or III) (OR 10.66, p = 0.030) and history of postoperative adjuvant therapy (OR 12.58, p = 0.040).

CONCLUSIONS

Identifying factors associated with preoperative or late postoperative seizures may help guide treatment strategies, eventually improving the quality of life for patients with meningiomas.

Focused review on seizures caused by meningiomas

BACKGROUND

Meningiomas belong to the most common intracranial neoplasms in adults. One of the most common symptoms patients with meningioma experience is seizures. However, it remains unclear whether prophylactic preoperative anticonvulsant treatment is worthwhile. Furthermore, it is not clear which patients are likely to experience seizures in the course of the disease. In recent years, many studies and meta-analyses addressed this question with particular contradictory results. Therefore, we aimed to identify the most important risk factors for seizures in patients with meningiomas.

METHODS

For the search terms "meningioma and seizure", "meningioma and epilepsy", and "Simpson and seizure" Medline query identified 865 articles. After applying inclusion and exclusion criteria, 20 papers were chosen for further study. The papers were analyzed for all risk factors for pre- and postoperative risk factors for seizures.

RESULTS

Preoperative seizures were mostly associated with extensive brain edema, localization, and bigger tumor size. Even though data were sometimes very contradictory, higher postoperative seizure rate in patients with meningioma was associated with distinct localizations, preoperative seizures, tumor size, brain edema, extent of resection, tumor recurrence, and new neurological deficits. There were no randomized trials showing a prophylactic effect of anticonvulsant drugs.

CONCLUSIONS

There are relevant risk factors for seizures in patients with meningioma. There is the need for a double blind randomized trial for the prophylactic use of antiepileptic drugs (AEDs).

Long-term control and predictors of seizures in intracranial meningioma surgery: a population-based study

BACKGROUND

The aim of this retrospective study was to investigate the long-term seizure control and antiepileptic drug (AED) prescriptions, as well as identifying predictors of seizure(s) before and after surgery in a population-based cohort of operated intracranial meningioma patients.

METHODS

A total of 113 consecutive adult (> 18 years old) patients with newly diagnosed meningioma operated at the Karolinska University Hospital between 2006 and 2008 were included and followed up until the end of 2015. Data on seizure activity and AED prescriptions were obtained through chart review and telephone interview. Logistic regression and survival analysis were applied to identify risk factors for pre- and postoperative seizures.

RESULTS

A total of 21/113 (18.6%) patients experienced seizures before surgery of which 8/21 (38.1%) went on to become seizure-free after surgery. Thirteen (14%) patients experienced new-onset seizures after surgery. The regression analysis revealed tumor diameter ≥ 3.5 cm as a risk factor for preoperative seizures (OR 3.83, 95% CI 1.14-12.87). Presence of headache (OR 0.19, 95% CI 0.05-0.76) and skull base tumor location (OR 0.14, 95% CI 0.04-0.44) decreased the risk of preoperative seizures. Postoperative seizures were associated with tumor diameter ≥ 3.5 cm (OR 2.65, 95% CI 1.06-6.62) and history of preoperative seizures (OR 3.50, 95% CI 1.55-7.90).

CONCLUSION

Seizures are common before and after intracranial meningioma surgery. Approximately one third of patients with preoperative seizures become seizure-free on long-term follow-up after surgery, while 14% experienced new-onset seizures after surgery. Larger tumor size, absence of headache, and non-skull base location were associated with preoperative seizures, while tumor size and preoperative seizures were associated with postoperative seizures.

Prediction of Histological Grade and Completeness of Resection of Intracranial Meningiomas: Role of Peritumoural Brain Edema

BACKGROUND

Meningioma is the commonest primary intracranial tumour in adults. Excision is curative for low grade meningioma, whereas high-grade meningioma requires adjuvant therapy following surgery. Several studies have examined the association between peritumoural brain Edema - a common feature in meningioma - and histological grading with mixed results. The present study attempted to elucidate this association and if peritumoural brain Edema affects the intra-operative judgement of surgeons on the completeness of resection.

METHODS

An observational study was conducted among those who underwent surgery for meningioma. Eighteen subjects were recruited each for low- and high-grades, respectively. Magnetic resonance imaging (MRI) prior to surgery was employed for interpreting the Edema index and MRI after surgery was used to determine residual tumour.

RESULTS

Median age was 50 years, male to female ratio was 1:3.5, 69.4% had peritumoural brain Edema and 75% had reported gross resection. Among the reported gross total resection cases, 40.7% had residual tumour. Analysis showed statistically significant association between peritumoural brain Edema (P = 0.027) and tumour volume (P = 0.001) with high-grade meningioma, however multivariate analysis did not present any association. No association was noted between judgement of tumour resection by surgeons and peritumoural brain Edema.

CONCLUSION

Odds ratio for peritumoural brain Edema remained high and the tumour volume exhibited marginal P-value marginal significance for prediction of high grade meningioma. These two factors may still contribute to the tumour grade and should be included in further studies on the prognosis of meningioma.

The role of prophylactic antiepileptic drugs for seizure prophylaxis in meningioma surgery: A systematic review

Meningiomas are the commonest type of primary brain tumours. Whilst most patients are seizure-free prior to surgery, antiepileptic drugs are frequently administered to reduce the risk of developing post-operative seizures. However, evidence to support their efficacy in providing this outcome is sparse. To this end, we performed a systematic review to assess the impact of prophylactic antiepileptic drugs on post-operative epilepsy rates in seizure-naïve patients undergoing craniotomy for resection of meningiomas. The literature search was performed using PubMed for studies published between January 1990 and November 2016. The total number of patients in each study was extracted and divided into cohorts according to administration of prophylactic antiepileptic drugs. Clinical characteristics, study type and post-operative epilepsy rates were recorded. A total of 11 studies involving 1143 patients met the selection criteria. There was no statistically significant difference in the number of patients who developed post-operative epilepsy in the cohort that received prophylactic antiepileptic drugs (20 of 766; 2.6%) and the cohort that did not (10 of 377; 2.7%) (Chi-square test; P=0.96). A detailed meta-analysis could not be performed due to the insufficiency in data reported. Based on the results of this systematic review, the routine use of antiepileptic drugs for seizure prophylaxis in seizure-naïve patients undergoing meningioma resection could not be substantiated. However, limitations of a systematic review should be considered on interpretation. High quality prospective randomised controlled trials are required to definitively answer this important clinical question.

Seizures and Epileptiform Discharges in Patients With Acute Subdural Hematoma

PURPOSE

Subdural hematomas (SDH) are associated with seizures and epileptiform discharges, but little is known about the prevalence and impact of seizures, status epilepticus (SE), and epileptiform discharges on outcomes in patients with isolated acute SDH (aSDH).

METHODS

Continuous EEG reports from 76 adult patients admitted to Rush University Medical Center with aSDH between January 2009 and March 2012 were reviewed. Clinical and radiographic findings, comorbidities, treatment, and outcome parameters, such as mortality, discharge destination, need for tracheostomy/percutaneous endoscopic gastrostomy placement, and length of stay (LOS), were assessed. Univariate and multivariate analyses were performed to assess the impact of clinical seizures, SE, and epileptiform EEG on outcomes.

RESULTS

Of 76 patients with aSDH who underwent EEG monitoring, 74 (97.4%) received antiseizure prophylaxis. Thirty-two (41.1%) patients had seizures, most of which were clinical seizures. Twenty-four (32%) patients had epileptiform EEG findings. Clinical or nonconvulsive SE was diagnosed in 12 (16%) patients. Clinical seizures were not associated with outcome parameters. Epileptiform EEG findings were independently associated with longer hospital LOS (13 vs. 8 days, P = 0.04) and intensive care unit LOS (10 vs. 4 days, P = 0.002). The SE also predicted longer intensive care unit LOS (10 vs. 4 days, P = 0.002). Neither epileptiform EEG nor SE was significantly related to mortality, discharge destination, or need for tracheostomy/percutaneous endoscopic gastrostomy placement.

CONCLUSIONS

Seizures and epileptiform EEG findings are very common in patients with aSDH despite antiseizure prophylaxis. While clinical seizures did not affect outcomes, the presence of epileptiform EEG findings and SE was independently associated with longer intensive care unit LOS and hospital LOS.

Clinical Course and Results of Surgery for Chronic Subdural Hematomas in Patients on Drugs Affecting Hemostasis

Objective

An apparent increase of use of drugs affecting hemostasis in our neurosurgical department since the 1990s has encouraged us to investigate whether these drugs influence the clinical course and results of surgery for chronic subdural hematoma (CSDH).

Methods

This retrospective analysis included 178 patients admitted for CSDH from 2007 to 2011 who were divided into two groups: on drugs affecting hemostasis (40; 22%) and no bleeding disorders (138; 78%). Medications in the first group included oral anticoagulants (33; 82.5%), antiplatelets (5; 12.5%) and low molecular weight heparins (2; 5%).

Results

The patients on drugs affecting hemostasis were older (74.3±7.4 vs. 68.4±14.8; p-value 0.01) and the group without bleeding disorders had more head trauma history (61% vs. 38%, p-value 0.01). The groups did not differ in bilateral hematoma rates (25% vs. 20%, p-value=NS). At diagnosis, mean hematoma thickness was lower in patients on drugs affecting hemostasis (18.7±7.4 mm vs. 21.9±7.9 mm, p-value<0.01). Average stay of hospital was 1 day longer in patients on drugs affecting hemostasis (11.7±4.1 vs.10.9±5.3, p-value=NS) and was related to the necessity of bleeding disorder reversal. Mean neurological status at presentation was similar between the groups (p-value=NS) as was the likelihood of hematoma recurrence (p-value=NS). Glasgow Outcome Scale results were comparable.

Conclusion

Patients on drugs affecting hemostasis are less often aware of a head trauma history, possibly suggesting a higher CSDH risk after minor trauma in this group. In these patients, smaller hematomas are symptomatic, probably due to faster hematoma formation. Drugs affecting hemostasis do not affect treatment results.

Epileptic Seizures in Patients Following Surgical Treatment of Acute Subdural Hematoma-Incidence, Risk Factors, Patient Outcome, and Development of New Scoring System for Prophylactic Antiepileptic Treatment (GATE-24 score)

OBJECT

Clinically evident or subclinical seizures are common manifestations in acute subdural hematoma (aSDH); however, there is a paucity of research investigating the relationship between seizures and aSDH. The purpose of this study is 2-fold: determine incidence and predictors of seizures and then establish a guideline in patients with aSDH to standardize the decision for prophylactic antiepileptic treatment.

METHOD

The author analyzed 139 patients with aSDH treated from 2007 until 2015. Baseline characteristics and clinical findings including Glasgow Coma Scale (GCS) at admission, 24 hours after operation, timing of operation, anticoagulation, and Glasgow Outcome Scale at hospital discharge and after 3 months were analyzed. Multivariate logistic regression analysis was performed to detect independent predictors of seizures, and a scoring system was developed.

RESULTS

Of 139 patients, overall incidence of seizures was 38%, preoperatively 16% and postoperatively 24%. Ninety percent of patients with preoperative seizures were seizure free after operation for 3 months. Independent predictors of seizures were GCS <9 (odds ratio [OR] 3.3), operation after 24 hours (OR 2.0), and anticoagulation (OR 2.2). Patients with seizures had a significantly higher rate of unfavorable outcome at hospital discharge (P = 0.001) and in 3-month follow-up (P = 0.002). Furthermore, a score system (GATE-24) was developed. In patients with GCS <14, anticoagulation, or surgical treatment 24 hours after onset, a prophylactic antiepileptic treatment is recommended.

CONCLUSION

Occurrence of seizures affected severity and outcomes after surgical treatment of aSDH. Therefore seizure prophylaxis should be considered in high-risk patients on the basis of the GATE-24 score to promote better clinical outcome.

Refractory epilepsy in children with brain tumors. The urgency of neurosurgery

In order to verify indications for surgery, 27 patients with refractory epileptic seizures and brain tumor, aged up to 19 years at the time of surgery, were studied between 1996 and 2013 and followed up for at least one year. The mean interval between the onset of seizures and the diagnosis of the tumor was 3.6 years, and from diagnosis to the surgery, 18 months. The location of the tumor was in the temporal lobe in 16, with ganglioglioma and dysembryoplastic neuroepithelial tumors being the most frequent. Among the patients, 92.5% and 90.4% were seizure-free in the first and fifth year after surgery, respectively. Twelve of 16 children were successful in becoming drug-free, with complete withdrawal by 3.2 years. Surgery proved to be potentially curative and safe in these cases, suggesting that the tumor diagnosis and surgery cannot be postponed.

Intracranial meningiomas and seizures: a review of the literature

BACKGROUND

Seizures are a common manifestation of brain tumors, but literature on the incidence of seizures before and after surgery for meningiomas is limited, and principles for use of antiepileptic drugs (AEDs) are controversial.

METHODS

This review is based on a MEDLINE search for articles from 1994 to 2014 describing intracranial meningioma and seizures or epilepsy, and AEDs treatment during and after surgery.

RESULTS

Up to 40 % of patients with symptomatic meningiomas present with seizures before operation. Tumor removal usually results in seizure control, but around 20 % of patients continue to have or develop new-onset seizures after surgery. Risk factors for seizures after surgery include preoperative seizures, tumor location, and extent of tumor removal. There are no solid data to support routine pre- or postoperative AED prophylaxis in seizure-free patients, and the decision to treat and the selection of AEDs should follow the general principles of treatment of focal epilepsies.

CONCLUSIONS

Seizures are a common manifestation of meningiomas, but about 80 % patients with preoperative seizures can be seizure free after tumor removal. Prospective controlled AED trials specifically on meningioma patients are much needed.

Peritumoral epilepsy: relating form and function for surgical success

Seizures are a prominent symptom in patients with both primary and secondary brain tumors. Medical management of seizure control in this patient group is problematic as the mechanisms linking tumorigenesis and epileptogenesis are poorly understood. It is possible that several mechanisms contribute to tumor-associated epileptic zone formation. In this review, we discuss key candidates that may be implicated in peritumoral epileptogenesis and, in so doing, hope to highlight areas for future research. Furthermore, we summarize the current role of antiepileptic medications in this type of epilepsy and examine the changes in surgical practice which may lead to improved seizure rates after tumor surgery. Lastly, we speculate on possible future preoperative and intraoperative considerations for improving seizure control after tumor resection.