Intracranial meningiomas and seizures: a review of the literature

Intracranial intricacies: Comprehensive analysis of rare skull base meningiomas-A single-center case series

This study paper's main goal is to report rare cases of skull base meningiomas that exemplify the complexities of diagnosis, therapy, and postoperative care. By describing these rare cases, we hope to advance knowledge of the clinical signs, difficulties, and prognoses of skull base meningiomas in a challenging anatomical setting. In the posterior cranial fossa, our investigation reveals a unique example of skull base meningioma that involved numerous cranial nerves and complex vasculature. A variety of visual abnormalities were present in the patient's clinical presentations, highlighting the wide range of symptoms that these tumors might cause depending on their precise positions. These cases highlight the critical importance of preoperative imaging, including high-resolution MRI and angiography, as well as the diagnostic difficulties these tumors pertain. By reporting these instances, our research adds to the body of knowledge about skull base meningiomas and offers insightful information about the nuances of their therapies. Our findings highlight the importance of individualized treatment plans, interdisciplinary cooperation, and the demand for continued study to better comprehend these convoluted tumors. Such studies are essential for advancing our knowledge of these enigmatic tumors, guiding clinical judgment, and eventually improving patient outcomes. These findings are important because they can fill information gaps, improve treatment plans, and encourage additional research in neuro-oncology.

Abstract

This study presents a series of three rare cases of skull base meningiomas, emphasizing the complexities in diagnosis, treatment, and postoperative care. The patients' clinical presentations and imaging highlighted the diverse symptoms and challenges associated with these tumors, found in intricate anatomical locations. The cases underscore the crucial role of preoperative high-resolution imaging and angiography in diagnostic accuracy. Surgical intervention, guided by a multidisciplinary approach, is pivotal in managing these demanding cases. Histopathological examinations confirmed atypical meningiomas. The postoperative phases involved meticulous care to ensure optimal recovery and functional outcomes. Our findings contribute to the understanding of skull base meningiomas, emphasizing the need for personalized treatment plans and ongoing research to improve patient outcomes in neuro-oncology.

Meningioma-Related Epilepsy: A Happy Ending?

(1) Background: More than one-third of patients with meningiomas experience at least one seizure during the course of their disease, and in the 20-50% of cases, seizure represents the onset symptom. After surgery, up to 30% of patients continue to have seizures, while others may experience them later; (2) Methods: The study analyzed retrospectively the risk factors for pre-operative seizures in a large cohort of 358 patients who underwent surgery for newly diagnosed brain meningioma; (3) Results: We identified age, peritumor edema, and location as risk factors for seizure at the onset. Patients with seizures differed from patients without seizures for the following characteristics: younger average age, lower pre-operative Karnofsky Performance Status (KPS), location on the convexity, lower Simpson Grade, lower incidence of pre-operative neurological deficits, and higher incidence of pre-operative peritumor edema. After 24 months, 88.2% of patients were classified as Engel class Ia, and no correlation with disease progression was observed; (4) Conclusions: Meningioma-related epilepsy has generally a positive outcome following surgery and it seems not to be linked to disease progression, even if further studies are needed.

The clinical and genomic features of seizures in meningiomas

Meningiomas are the most common central nervous system tumors. Although these tumors are extra-axial, a relatively high proportion (10%-50%) of meningioma patients have seizures that can substantially impact the quality of life. Meningiomas are believed to cause seizures by inducing cortical hyperexcitability that results from mass effect and cortical irritation, brain invasion, or peritumoral brain edema. In general, meningiomas that are associated with seizures have aggressive features, with risk factors including atypical histology, brain invasion, and higher tumor grade. Somatic NF2 mutated meningiomas are associated with preoperative seizures, but the effect of the driver mutation is mediated through atypical features. While surgical resection is effective in controlling seizures in most patients with meningioma-related epilepsy, a history of seizures and uncontrolled seizures prior to surgery is the most significant predisposing factor for persistent postoperative seizures. Subtotal resection (STR) and relatively larger residual tumor volume are positive predictors of postoperative seizures. Other factors, including higher WHO grade, peritumoral brain edema, and brain invasion, are inconsistently associated with postoperative seizures, suggesting they might be crucial in the development of an epileptogenic focus, but do not appear to play a substantial role after seizure activity has been established. Herein, we review and summarize the current literature surrounding meningioma-related epilepsy and underscore the interaction of multiple factors that relate to seizures in patients with meningioma.

Surgical morbidity of the extradural anterior petrosal approach: the Lariboisière experience

OBJECTIVE

Concerns about the approach-related morbidity of the extradural anterior petrosal approach (EAPA) have been raised, especially regarding temporal lobe and venous injuries, hearing impairment, facial nerve palsy, cerebrospinal fluid fistula, and seizures. There is lack in the literature of studies with detailed analysis of surgical complications. The authors have presented a large series of patients who were treated with EAPA, focusing on complications and their avoidance.

METHODS

The authors carried out a retrospective review of patients who underwent EAPA at their institution between 2012 and 2021. They collected preoperative clinical characteristics, operative reports, operative videos, findings on neuroimaging, histological diagnosis, postoperative course, and clinical status at last follow-up. For pathologies without petrous bone invasion, the amount of petrous apex drilling was calculated and classified as low (< 70% of the volume) or high (≥ 70%). Complications were dichotomized as approach related and resection related.

RESULTS

This study included 49 patients: 26 with meningiomas, 10 brainstem cavernomas, 4 chondrosarcomas, 4 chordomas, 2 schwannomas, 1 epidermoid cyst, 1 cholesterol granuloma, and 1 osteoblastoma. The most common approach-related complications were temporal lobe injury (6.1% of patients), seizures (6.1%), pseudomeningocele (6.1%), hearing impairment (4.1%), and dry eye (4.1%). Approach-related complications occurred most commonly in patients with a meningioma (p = 0.02) and Meckel's cave invasion (p = 0.02). Gross-total or near-total resection was correlated with a higher rate of tumor resection-related complications (p = 0.02) but not approach-related complications (p = 0.76). Inferior, lateral, and superior tumoral extension were not correlated with a higher rate of tumor resection-related complications. No correlation was found between high amount of petrous bone drilling and approach- or resection-related complications.

CONCLUSIONS

EAPA is a challenging approach that deals with critical neurovascular structures and demands specific skills to be safely performed. Contrary to general belief, its approach-related morbidity seems to be acceptable at dedicated skull base centers. Morbidity can be lowered with careful examination of the preoperative neuroradiological workup, appropriate patient selection, and attention to technical details.

The prevalence and severity of fatigue in meningioma patients and its association with patient-, tumor- and treatment-related factors

Background

Fatigue is a commonly reported and severe symptom in primary brain tumor patients, but the exact occurrence in meningioma patients is unknown. This study aimed to determine the frequency and severity of fatigue in meningioma patients as well as associations between the level of fatigue and patient-, tumor-, and treatment-related factors.

Methods

In this multicenter cross-sectional study, meningioma patients completed questionnaires on fatigue (MFI-20), sleep (PSQI), anxiety and depression (HADS), tumor-related symptoms (MDASI-BT), and cognitive functioning (MOS-CFS). Multivariable regression models were used to evaluate the independent association between fatigue and each patient-, tumor-, and treatment-related factor separately, corrected for relevant confounders.

Results

Based on predetermined in- and exclusion criteria, 275 patients, on average 5.3 (SD = 2.0) year since diagnosis, were recruited. Most patients had undergone resection (92%). Meningioma patients reported higher scores on all fatigue subscales compared to normative data and 26% were classified as fatigued. Having experienced a complication due to resection (OR 3.6, 95% CI: 1.8-7.0), having received radiotherapy (OR 2.4, 95% CI: 1.2-4.8), a higher number of comorbidities (OR 1.6, 95% CI: 1.3-1.9) and lower educational level (low level as reference; high level OR 0.3, 95% CI: 0.2-0.7) were independently associated with more fatigue.

Conclusions

Fatigue is a frequent problem in meningioma patients even many years after treatment. Both patient- and treatment-related factors were determinants of fatigue, with the treatment-related factors being the most likely target for intervention in this patient population.

Predictors of postoperative seizure outcome in supratentorial meningioma

OBJECTIVE

Meningiomas are the most common primary intracranial tumor. Seizures are common sequelae of meningioma development. Meningioma patients with seizures can be effectively treated with resection, with reports of seizure freedom of 60%-90%. Still, many patients manifest persistent epilepsy. Determining factors associated with worsened seizure outcomes remains critical in improving the quality of life for these patients. The authors sought to identify clinical, radiological, and histological factors associated with worse seizure outcomes in patients with supratentorial meningioma and preoperative seizures.

METHODS

The authors retrospectively reviewed the charts of 384 patients who underwent meningioma resection from 2008 to 2020. The charts of patients with a documented history of preoperative seizures were further reviewed for clinical, radiological, operative, perioperative, histological, and postoperative factors associated with seizures. Engel class at last follow-up was retrospectively assigned by the authors and further grouped into favorable (class I) and worse (class II-IV) outcomes. Factors were subsequently compared by group using comparative statistics. Univariable and multivariable regression models were utilized to identify independent predictors of worse seizure outcome.

RESULTS

Fifty-nine patients (15.4%) were found to have preoperative seizures, of whom 57 had sufficient postoperative data to determine Engel class outcome. Forty-two patients (74%) had Engel class I outcomes. The median follow-up was 17 months. Distinct margins on preoperative imaging (p = 0.012), Simpson grade I resection (p = 0.004), postresection ischemia (p = 0.019), WHO grade (p = 0.019), and recurrent disease (p = 0.015) were found to be the strongest predictors of Engel class outcome in univariable logistic regression. MIB-1 index (p = 0.001) and residual volume (p = 0.014) at last follow-up were found to be the strongest predictors of Engel class outcome in univariable generalized linear regression. Postresection ischemia (p = 0.012), WHO grade (p = 0.022), recurrent disease (p = 0.038), and MIB-1 index (p = 0.002) were found to be the strongest independent predictors of Engel class outcomes in multivariable analysis.

CONCLUSIONS

Postresection ischemia, higher WHO grade, elevated MIB-1 index, and disease recurrence independently predict postresection seizure persistence in patients with supratentorial meningioma. Further understanding of the etiology of these markers may aid in elucidation of this complex disease process and guide management to prevent worse outcomes.

Recurrence risk after a first remote symptomatic seizure in adults: Epilepsy or not?

The ILAE practical definition of epilepsy has a one seizure possibility to diagnose epilepsy after a first seizure if the recurrence risk is very high. The recurrence risk after a first seizure in brain disorders (first remote seizure) is often high, but varies with etiology, so more specific information is needed for clinical practice. This review describes etiology-specific recurrence risks in adults with a first remote seizure in stroke, traumatic brain injury, infections, dementia, multiple sclerosis, and tumors. Most studies are short, single center, and retrospective. Inclusion criteria, outcome ascertainment, and results vary. Few patient categories are clearly above the epilepsy threshold of recurrence risk, and there are surprisingly little data for important etiologies like brain infections. Beside stroke, severe TBI could have a sufficiently high recurrence risk for early epilepsy diagnosis, but more studies are needed, preferably prospective ones. The literature is uninformative regarding which seizures qualify as remote. The clinical implication of the low level of available evidence is that for other etiologies than stroke, seizure recurrence remains the most appropriate indicator of epilepsy for most patients with a first remote seizure. Nonetheless, there are worrying indications of a diagnostic drift, which puts patients with a preexisting brain disorder at risk of misdiagnosis. Although there are drawbacks to an intermediate term like "possible epilepsy," it could perhaps be useful in cases when the recurrence risk is high, but epilepsy criteria are not definitely met after a first remote seizure.

Clinical and genomic factors associated with seizures in meningiomas

OBJECTIVE

The association of seizures with meningiomas is poorly understood. Moreover, any relationship between seizures and the underlying meningioma genomic subgroup has not been studied. Herein, the authors report on their experience with identifying clinical and genomic factors associated with preoperative and postoperative seizure presentation in meningioma patients.

METHODS

Clinical and genomic sequencing data on 394 patients surgically treated for meningioma at Yale New Haven Hospital were reviewed. Correlations between clinical, histological, or genomic variables and the occurrence of preoperative and postoperative seizures were analyzed. Logistic regression models were developed for assessing multiple risk factors for pre- and postoperative seizures. Mediation analyses were also conducted to investigate the causal pathways between genomic subgroups and seizures.

RESULTS

Seventeen percent of the cohort had presented with preoperative seizures. In a univariate analysis, patients with preoperative seizures were more likely to have tumors with a somatic NF2 mutation (p = 0.020), WHO grade II or III tumor (p = 0.029), atypical histology (p = 0.004), edema (p < 0.001), brain invasion (p = 0.009), and worse progression-free survival (HR 2.68, 95% CI 1.30-5.50). In a multivariate analysis, edema (OR 3.11, 95% CI 1.46-6.65, p = 0.003) and atypical histology (OR 2.00, 95% CI 1.03-3.90, p = 0.041) were positive predictors of preoperative seizures, while genomic subgroup was not, such that the effect of an NF2 mutation was indirectly mediated through atypical histology and edema (p = 0.012). Seizure freedom was achieved in 83.3% of the cohort, and only 20.8% of the seizure-free patients, who were more likely to have undergone gross-total resection (p = 0.031), were able to discontinue antiepileptic drug use postoperatively. Preoperative seizures (OR 3.54, 95% CI 1.37-9.12, p = 0.009), recurrent tumors (OR 2.89, 95% CI 1.08-7.74, p = 0.035), and tumors requiring postoperative radiation (OR 2.82, 95% CI 1.09-7.33, p = 0.033) were significant predictors of postoperative seizures in a multivariate analysis.

CONCLUSIONS

Seizures are relatively common at meningioma presentation. While NF2-mutated tumors are significantly associated with preoperative seizures, the association appears to be mediated through edema and atypical histology. Patients who undergo radiation and/or have a recurrence are at risk for postoperative seizures, regardless of the extent of resection. Preoperative seizures may indeed portend a more potentially aggressive molecular entity and challenging clinical course with a higher risk of recurrence.

Prophylactic AEDs Treatment for Patients With Supratentorial Meningioma Does Not Reduce the Rate of Perioperative Seizures: A Retrospective Single-Center Cohort Study

Meningiomas, the most common brain tumor, inevitably require surgical treatment. However, the efficacy of prophylactic antiepileptic drugs (AEDs), in reducing the frequency of new-onset seizures during the perioperative period remains controversial. To further clarify if prophylactic antiepileptic drug treatment for patients with meningioma had value, we reviewed the medical records of 186 supratentorial meningioma patients who were operated at our hospital between 2016 and 2018. SPSS 24.0 software was used for statistical analysis. The results of univariate analysis showed that factors including age, sex, the course of the disease (years), maximum cross-sectional area of the tumor, location of the tumor, multiple or single tumors, adjacent to the cortex, peritumoral brain edema, World Health Organization classification, and peritumoral adhesion were not associated with perioperative seizures (P >0.05). Furthermore, the results of multivariate analysis revealed hydrocephalus (OR 4.87 P = 0.05) and non-skull base location (OR 1.88 P = 0.04) were significant risk factors for perioperative in-hospital seizures. Prophylactic valproic acid treatment did not contribute to the alleviation of perioperative seizures (OR 1.76 P = 0.04). However, Multivariate logistic regression analyses excluding the patients with seizures before operation confirmed prophylactic valproic acid treatment did not reduce the frequency of seizures during the perioperative period (OR 1.84 P = 0.04). Taken together, the data suggest that prophylactic valproic acid treatment for patients with supratentorial meningioma does not reduce the rate of perioperative seizures.

The Ki-67 Proliferation Index as a Marker of Time to Recurrence in Intracranial Meningioma

BACKGROUND

There are examples of incongruence between the WHO grade and clinical course in meningioma patients. This incongruence between WHO grade and recurrence has led to search for other prognostic histological markers.

OBJECTIVE

To study the correlation between the Ki-67 proliferative index (PI), risk of recurrence, and recurrence rates in meningioma patients.

METHODS

We prospectively collected pathological diagnosis of de novo consecutive meningiomas. In total, we followed 159 patients with clinical controls until recurrence, death, or emigration. We estimated the correlation between risk of recurrence and Ki-67 PI when adjusted for age at diagnosis, sex, WHO grade, extent of surgical resection, and tumor location. We estimated the cumulative incidence of recurrence when considering death without recurrence a competing risk. We report recurrence rates per 100 person-years.

RESULTS

A 1%-point increase of Ki-67 PI yielded a hazard ratio of 1.12 (95% CI: 1.01-1.24) in a multivariate analysis. The cumulative incidence of recurrence was 3% for Ki-67 0% to 4% vs 19% for Ki-67 > 4% meningiomas after 1 yr, but 24% vs 35%, respectively, after 10 yr. There was no significant difference in mean Ki-67 PI between nonrecurrent and recurrent meningioma in a 2-sample t-test (P = .08). The strongest relationship was detected between Ki-67 PI and time to recurrence: Ki-67 < 4% meningiomas recurred after median 4.8 yr, compared to 0.60 to 0.75 yr for patients with higher Ki-67 PI.

CONCLUSION

Ki-67 PI was a marker for time to recurrence rather than a predictor of recurrence. Ki-67 PI may be utilized for patient tailored follow-up.

[Management of tumoral epilepsy in meningioma surgery: Review of the literature and survey of French national practices]

Prophylaxis or treatment of tumor-associated seizures is adaily concern in neurosurgical practice but is often guided by the surgeon's habits rather than evidence from clinical trials, which is lacking. The present study reviews the literature on the incidence, clinical aspects and treatment of epilepsy and epileptic seizures in patients undergoing surgery for meningioma. Based on the published data, we then performed a French nationwide survey of neurosurgeons' practices regarding perioperative management of meningioma-related epilepsy and epileptic seizures.

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.

Brain invasion and the risk of seizures in patients with meningioma

OBJECTIVE

Identification of risk factors for perioperative epilepsy remains crucial in the care of patients with meningioma. Moreover, associations of brain invasion with clinical and radiological variables have been largely unexplored. The authors hypothesized that invasion of the cortex and subsequent increased edema facilitate seizures, and they compared radiological data and perioperative seizures in patients with brain-invasive or noninvasive meningioma.

METHODS

Correlations of brain invasion with tumor and edema volumes and preoperative and postoperative seizures were analyzed in univariate and multivariate analyses.

RESULTS

Totals of 108 (61%) females and 68 (39%) males with a median age of 60 years and harboring totals of 92 (52%) grade I, 79 (45%) grade II, and 5 (3%) grade III tumors were included. Brain invasion was found in 38 (22%) patients and was absent in 138 (78%) patients. The tumors were located at the convexity in 72 (41%) patients, at the falx cerebri in 26 (15%), at the skull base in 69 (39%), in the posterior fossa in 7 (4%), and in the ventricle in 2 (1%); the median tumor and edema volumes were 13.73 cm3 (range 0.81-162.22 cm3) and 1.38 cm3 (range 0.00-355.80 cm3), respectively. As expected, edema volume increased with rising tumor volume (p < 0.001). Brain invasion was independent of tumor volume (p = 0.176) but strongly correlated with edema volume (p < 0.001). The mean edema volume in noninvasive tumors was 33.0 cm3, but in invasive tumors, it was 130.7 cm3 (p = 0.008). The frequency of preoperative seizures was independent of the patients' age, sex, and tumor location; however, the frequency was 32% (n = 12) in patients with invasive meningioma and 15% (n = 21) in those with noninvasive meningioma (p = 0.033). In contrast, the probability of detecting brain invasion microscopically was increased more than 2-fold in patients with a history of preoperative seizures (OR 2.57, 95% CI 1.13-5.88; p = 0.025). In univariate analyses, the rate of preoperative seizures correlated slightly with tumor volume (p = 0.049) but strongly with edema volume (p = 0.014), whereas seizure semiology was found to be independent of brain invasion (p = 0.211). In multivariate analyses adjusted for age, sex, tumor location, tumor and edema volumes, and WHO grade, rising tumor volume (OR 1.02, 95% CI 1.00-1.03; p = 0.042) and especially brain invasion (OR 5.26, 95% CI 1.52-18.15; p = 0.009) were identified as independent predictors of preoperative seizures. Nine (5%) patients developed new seizures within a median follow-up time of 15 months after surgery. Development of postoperative epilepsy was independent of all clinical variables, including Simpson grade (p = 0.133), tumor location (p = 0.936), brain invasion (p = 0.408), and preoperative edema volume (p = 0.081), but was correlated with increasing preoperative tumor volume (p = 0.004). Postoperative seizure-free rates were similar among patients with invasive and those with noninvasive meningioma (p = 0.372).

CONCLUSIONS

Brain invasion was identified as a new and strong predictor for preoperative, but not postoperative, seizures. Although also associated with increased peritumoral edema, seizures in patients with invasive meningioma might be facilitated substantially by cortical invasion itself. Consideration of seizures in consultations between the neurosurgeon and neuropathologist can improve the microscopic detection of brain invasion.

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).

Common Histologically Benign Tumors of the Brain

PURPOSE OF REVIEW

As a group, benign tumors account for the majority of primary neoplasms affecting the central nervous system (CNS). This article reviews the epidemiology, clinical presentation, neuroimaging features, and management of the most common of these tumors: meningiomas, schwannomas, and pituitary adenomas.

RECENT FINDINGS

Awareness of the most common nonmalignant tumors of the CNS and their management guidelines is important as many of these tumors are managed conservatively, with neurologists playing a primary role in both surveillance and symptom management. Knowledge of the varied neurologic consequences of these tumors allows optimizing interventions that improve quality of life in people living with these tumors without incurring treatment-related complications. Awareness of the clinical features that require surgery, radiation therapy, or chemotherapy is imperative. Finally, important discoveries in both germline and somatic mutations underlying some of these lesions have contributed to the launch of several novel drug trials for these tumors.

SUMMARY

As a group, nonmalignant neoplasms are the most common neoplasms affecting the CNS in adults. Because of their unique neuroanatomic location or containment within the bony skull, these histologically benign lesions can cause significant neurologic morbidity. Management with a multidisciplinary team that includes neurologists, neuro-oncologists, radiologists, neurosurgeons, radiation oncologists, otolaryngologists, pathologists, neuropsychologists, physiatrists, and others is necessary for the optimal management of these lesions.

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.

Imaging for Adults With Seizures and Epilepsy

PURPOSE OF REVIEW

This article discusses structural and functional neuroimaging findings in patients with seizures and epilepsy. The indications for neuroimaging in these patients and the potential diagnostic utility of these studies are presented.

RECENT FINDINGS

Patients presenting with new seizures typically require urgent imaging to rule out a critical underlying cause. MRI is the structural neuroimaging procedure of choice in individuals with epilepsy. Specific epilepsy protocols should be considered to increase the diagnostic yield of neuroimaging in patients with structural lesions associated with focal or generalized seizures. Common epileptogenic pathologic processes include mesial temporal sclerosis, malformations of cortical development, focal encephalomacia, primary brain tumors, vascular malformations, and neurocysticercosis. Functional neuroimaging studies are usually restricted to the evaluation of patients with drug-resistant focal epilepsy who are being considered for surgical treatment.

SUMMARY

The role of neuroimaging in epilepsy depends on the appropriate clinical indication. In patients without known epilepsy presenting with acute seizures, structural imaging is essential to rule out an underlying etiology (eg, subdural hematoma) that may require a specific therapeutic intervention. In individuals with new or previously uninvestigated epilepsy, MRI serves multiple purposes, including identifying a causative focal lesion and helping to diagnose the epilepsy type. In a significant number of patients with epilepsy, the MRI results are normal or reveal indeterminate findings. For patients with drug-resistant focal epilepsy, functional neuroimaging techniques, such as fludeoxyglucose-positron emission tomography (FDG-PET), ictal single-photon emission computed tomography (SPECT), or functional MRI (fMRI), may assist in surgical planning, especially in patients with MRI-negative epilepsy, whose prognosis for a seizure-free outcome after surgery is worse than for patients with an epileptogenic lesion on structural MRI.

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.