Seizure control following surgery in supratentorial cavernous malformations: a retrospective study in 77 patients

Hemorrhage of cerebral cavernous malformation in third trimester of pregnancy

Cerebral cavernous malformation is a rare but important cause of cerebral hemorrhage in pregnancy and puerperium. In pregnancy, cavernomas can more easily bleed as a result of increased female hormones and growth factors such as vascular endothelial growth factor. We present the case of a pregnant woman who had been diagnosed with a cerebral cavernoma about ten years previously, after repeated headache episodes; at the 28th week of pregnancy the woman was hospitalized for epileptic seizures and active bleeding from the anterior cerebral artery. We describe the management of the case, the decision for a preterm delivery and for a resolutive neurosurgical procedure.

Assessing the Relationship between Surgical Timing and Postoperative Seizure Outcomes in Cavernoma-Related Epilepsy: A Single-Institution Retrospective Analysis of 63 Patients with a Review of the Literature

Background: Patients with supratentorial cavernous malformations (SCMs) commonly present with seizures. First-line treatments for cavernoma-related epilepsy (CRE) include conservative management (antiepileptic drugs (AEDs)) and surgery. We compared seizure outcomes of CRE patients after early (≤6 months) vs. delayed (>6 months) surgery. Methods: We compared outcomes of CRE patients with SCMs surgically treated at our large-volume cerebrovascular center (1 January 2010-31 July 2020). Patients with 1 sporadic SCM and ≥1-year follow-up were included. Primary outcomes were International League Against Epilepsy (ILAE) class 1 seizure freedom and AED independence. Results: Of 63 CRE patients (26 women, 37 men; mean ± SD age, 36.1 ± 14.6 years), 48 (76%) vs. 15 (24%) underwent early (mean ± SD, 2.1 ± 1.7 months) vs. delayed (mean ± SD, 6.2 ± 7.1 years) surgery. Most (32 (67%)) with early surgery presented after 1 seizure; all with delayed surgery had ≥2 seizures. Seven (47%) with delayed surgery had drug-resistant epilepsy. At follow-up (mean ± SD, 5.4 ± 3.3 years), CRE patients with early surgery were more likely to have ILAE class 1 seizure freedom and AED independence than those with delayed surgery (92% (44/48) vs. 53% (8/15), p = 0.002; and 65% (31/48) vs. 33% (5/15), p = 0.03, respectively). Conclusions: Early CRE surgery demonstrated better seizure outcomes than delayed surgery. Multicenter prospective studies are needed to validate these findings.

Clinical Features and Treatment of Pediatric Cerebral Cavernous Malformations

Cerebral cavernous malformation (CCM) is a vascular anomaly commonly found in children and young adults. Common clinical presentations of pediatric patients with CCMs include headache, focal neurological deficits, and seizures. Approximately 40% of pediatric patients are asymptomatic. Understanding the natural history of CCM is crucial and hemorrhagic rates are higher in patients with an initial hemorrhagic presentation, whereas it is low in asymptomatic patients. There is a phenomenon known as temporal clustering in which a higher frequency of symptomatic hemorrhages occurs within a few years following the initial hemorrhagic event. Surgical resection remains the mainstay of treatment for pediatric CCMs. Excision of a hemosiderin-laden rim is controversial regarding its impact on epilepsy outcomes. Stereotactic radiosurgery is an alternative treatment, especially for deepseated CCMs, but its true efficacy needs to be verified in a clinical trial.

Cavernous malformations of the central nervous system: An international consensus statement

Introduction

Cavernous malformations (CM) of the central nervous system constitute rare vascular lesions. They are usually asymptomatic, which has allowed their management to become quite debatable. Even when they become symptomatic their optimal mode and timing of treatment remains controversial.

Research question

A consensus may navigate neurosurgeons through the decision-making process of selecting the optimal treatment for asymptomatic and symptomatic CMs.

Material and methods

A 17-item questionnaire was developed to address controversial issues in relation to aspects of the treatment, surgical planning, optimal surgical strategy for specific age groups, the role of stereotactic radiosurgery, as well as a follow-up pattern. Consequently, a three-stage Delphi process was ran through 19 invited experts with the goal of reaching a consensus. The agreement rate for reaching a consensus was set at 70%.

Results

A consensus for surgical intervention was reached on the importance of the patient's age, symptomatology, and hemorrhagic recurrence; and the CM's location and size. The employment of advanced MRI techniques is considered of value for surgical planning. Observation for asymptomatic eloquent or deep-seated CMs represents the commonest practice among our panel. Surgical resection is considered when a deep-seated CM becomes symptomatic or after a second bleeding episode. Asymptomatic, image-proven hemorrhages constituted no indication for surgical resection for our panelists. Consensus was also reached on not resecting any developmental venous anomalies, and on resecting the associated hemosiderin rim only in epilepsy cases.

Discussion and conclusion

Our Delphi consensus provides an expert common practice for specific controversial issues of CM patient management.

The First Potentially Causal Genetic Variant Documented in a Polish Woman with Multiple Cavernous Malformations of the Brain

Cerebral cavernous malformations (CCMs) are relatively common in the central nervous system. They occur in two forms, sporadic and familial (FCCMs). Three genes are recognized to be associated with FCCM, including CCM1, CCM2, and CCM3, the latter also called PDCD10. In this article, we describe a single-nucleotide variant in the PDCD10 gene in a 23-year-old Polish female with CCM. The NM_007217.4 (PDCD10): c.395+1G>A variant destroys the canonical splice donor site following exon 6. This is the first reported genetically characterized case of CCM (FCCM) in Poland.

Cavernoma-Related Epilepsy: Postoperative Epilepsy Outcome and Analysis of the Predictive Factors, Case Series

BACKGROUND

Epilepsy is common in patients harboring cavernous malformation, and surgery is reported to be an effective treatment. However, few patients still experience seizures after surgery. We analyzed the outcome and predictive factors after cavernoma-related epilepsy (CRE) surgery.

METHODS

A database was created for all patients with CRE treated surgically from 2003 to 2020 at a university hospital. A chart review, perioperative epilepsy workup, surgical strategies, and postoperative and follow-up notes were analyzed. Postoperative seizure outcome was evaluated according to the Engel classification.

RESULTS

Thirty-seven patients (40.5% women; mean age 39.1 ± 14.5 years) were studied. The mean follow-up time was 5.6 ± 3.9 years. Among 37 patients, 32 (86.5%) achieved Engel class I at the last follow-up. Engel class II was found in 1 (2.7%), Engel class III in 1 (2.7%), and Engel class IV in 3 (8.1%) cases. Engel class Ia was observed in 23 patients (62.2%). None of the patients had a worse seizure outcome after the operation (Engel class IVc). Univariate and multivariate analysis showed that short-standing, sporadic, or low-frequent (≤3) seizures were the only variables significantly associated with seizure freedom, whereas longstanding, drug-resistant, or high-frequent seizure history were associated with worse seizure outcomes.

CONCLUSIONS

Surgical treatment results in favorable seizure control in most patients after CRE surgery. Long duration of epilepsy before surgery, high seizure frequency, and drug-resistant epilepsy could have a negative effect on seizure outcome (Engel class II-IV). Therefore, early surgical resection of the cavernoma after careful presurgical planning is recommended to achieve an optimal result.

Intraoperative magnetic resonance imaging in epilepsy surgery: A systematic review and meta-analysis

This systematic review investigated the added value of intraoperative magnetic resonance imaging (iMRI)-guidance in epilepsy surgery, compared to conventional non-iMRI surgery, with respect to the rate of gross total resection (GTR), postoperative seizure freedom, neurological deficits, non-neurological complications and reoperations. A comprehensive literature search was conducted using Medline, Embase, PubMed, and Cochrane Reviews databases. Randomized control trials, case control or cohort studies, and surgical case series published from January 1993 to February 2021 that reported on iMRI-guided epilepsy surgery outcomes for either adults or children were eligible for inclusion. Studies comparing iMRI-guided epilepsy surgery to non-iMRI surgery controls were selected for meta-analysis using random-effects models. Forty-two studies matched the selection criteria and were used for qualitative synthesis and ten of these were suitable for meta-analysis. Overall, studies included various 0.2-3.0 Tesla iMRI systems, contained small numbers with heterogenous clinical characteristics, utilized subjective GTR reporting, and had variable follow-up durations. Meta-analysis demonstrated that the use of iMRI-guidance led to statistically significant higher rates of GTR (RR = 1.31 [95% CI = 1.10-1.57]) and seizure freedom (RR = 1.44 [95% CI = 1.12-1.84]), but this was undermined by moderate to significant statistical heterogeneity between studies (I² = 55% and I² = 71% respectively). Currently, there is only level III-2 evidence supporting the use of iMRI-guidance over conventional non-iMRI epilepsy surgery, with respect to the studied outcomes.

Treatment of Cerebral Cavernous Malformations Presenting With Seizures: A Systematic Review and Meta-Analysis

Background: Cerebral cavernous malformations (CCMs) presenting with seizures can be treated with neurosurgery or radiosurgery, but the ideal treatment remains unclear. Currently, there is no adequate randomized controlled trial comparing surgical treatment and radiotherapy for epileptogenic CCMs. Therefore, we conducted a systematic review and meta-analysis of available data from published literature to compare the efficacy and safety of neurosurgery and radiosurgery for epileptogenic CCMs. Methods: We performed a comprehensive search of the Ovid MEDLINE, Web of Science, PubMed, China Biological Medicine and China National Knowledge Infrastructure databases for studies published between January 1994 and October 2019. The search terms were as follows: "epilepsy," "seizures," "brain cavernous hemangioma," "cerebral cavernous malformation," "cerebral cavernous hemangioma," "hemangioma, cavernous, central nervous system." Two researchers independently extracted the data and reviewed all the articles. We compared the advantages and disadvantages of the two treatments. Results: A total of 45 studies were included in our analysis. Overall, the seizure control rate was 79% (95% CI: 75-83%) for neurosurgery and 49% (95% CI: 38-59%) for radiosurgery. In the neurosurgery studies, 4.4% of patients experienced permanent morbidity, while no patients in the radiotherapy studies had permanent morbidity. In addition, the results of subgroup analysis showed that ethnicity, CCMs location and average lesion number are likely significant factors influencing the seizure outcome following treatment. Conclusions: The epilepsy control rate after neurosurgery was higher than that after radiosurgery, but neurosurgery also had a relatively higher rate of permanent morbidity.

Cerebral cavernous malformation: Management and outcome during pregnancy and puerperium. A systematic review of literature

INTRODUCTION

Cerebral cavernomas malformations (CCMs) are vascular malformations that occur with an incidence of 0,4-0,8 % in general population. The most feared complication is cerebral hemorrhage. Currently there are no guidelines for pregnant women with CCMs. Some authors claimed that many physiological changes related to pregnancy could be linked to an high risk of rupture and bleeding of the cerebral cavernoma. However, more recent studies highlight that the presence of cerebral cavernomatosis is not a contraindication for pregnancy and that the risk of bleeding is similar in pregnant and in non-pregnant women.

AIM OF THE STUDY

The purpose of our work is to analyze, through the study of controversial findings in literature, all the information currently available trying to establish a common approach for management of women with cerebral cavernomatosis in pregnancy, during childbirth and in the puerperium.

FINDINGS

In accordance with existing literature, pregnancy does not appear to be a significant risk factor for the worsening of clinical manifestations associated with the presence of CCMs. Vaginal delivery is not contraindicated in patients with CCMs and there is no indication to perform cesarean section to reduce the incidence of hemorrhage. The only indication for neurosurgery of CCMs in pregnancy is the presence of rapidly progressive symptoms and should be postponed to the puerperium if arises after 30 weeks. The puerperium is a critical time for the woman with cavernomas for the possibility of bleeding and clinical observation must be continued.

CONCLUSION

The patients with a diagnosis of a CCMs can have a pregnancy without any particular risk to themselves and the fetus but should be addressed to highly specialized obstetrics center to assesses the initial individual risk related to their pathology and to follow the pregnancy.

Predictors of Epileptic Seizures and Ability to Work in Supratentorial Cavernous Angioma Located Within Eloquent Brain Areas

BACKGROUND

The postoperative outcomes and the predictors of seizure control are poorly studied for supratentorial cavernous angiomas (CA) within or close to the eloquent brain area.

OBJECTIVE

To assess the predictors of preoperative seizure control, postoperative seizure control, and postoperative ability to work, and the safety of the surgery.

METHODS

Multicenter international retrospective cohort analysis of adult patients benefitting from a functional-based surgical resection with intraoperative functional brain mapping for a supratentorial CA within or close to eloquent brain areas.

RESULTS

A total of 109 patients (66.1% women; mean age 38.4 ± 12.5 yr), were studied. Age >38 yr (odds ratio [OR], 7.33; 95% confidence interval [CI], 1.53-35.19; P = .013) and time to surgery > 12 mo (OR, 18.21; 95% CI, 1.11-296.55; P = .042) are independent predictors of uncontrolled seizures at the time of surgery. Focal deficit (OR, 10.25; 95% CI, 3.16-33.28; P < .001) is an independent predictor of inability to work at the time of surgery. History of epileptic seizures at the time of surgery (OR, 7.61; 95% CI, 1.67-85.42; P = .003) and partial resection of the CA and/or of the hemosiderin rim (OR, 12.02; 95% CI, 3.01-48.13; P < .001) are independent predictors of uncontrolled seizures postoperatively. Inability to work at the time of surgery (OR, 19.54; 95% CI, 1.90-425.48; P = .050), Karnofsky Performance Status ≤ 70 (OR, 51.20; 95% CI, 1.20-2175.37; P = .039), uncontrolled seizures postoperatively (OR, 105.33; 95% CI, 4.32-2566.27; P = .004), and worsening of cognitive functions postoperatively (OR, 13.71; 95% CI, 1.06-176.66; P = .045) are independent predictors of inability to work postoperatively.

CONCLUSION

The functional-based resection using intraoperative functional brain mapping allows safe resection of CA and the peripheral hemosiderin rim located within or close to eloquent brain areas.

Is additional mesial temporal resection necessary for intractable epilepsy with cavernous malformations in the temporal neocortex?

PURPOSE

Cavernous malformation (CM) in the temporal neocortex causes intractable epilepsy. Whether to resect additional mesial temporal structures in addition to the lesionectomy is a still controversial issue. To clarify the need for the procedure, we retrospectively analyzed pre- and postoperative clinical data of patients with surgically removed CM.

SUBJECTS AND METHODS

We included data from 18 patients with CM in the temporal neocortex who presented with intractable epilepsy. Eleven patients of our early series were treated with extended resection, i.e., lesionectomy and the resection of additional mesial temporal structures. Seven patients underwent lesionectomy, i.e., removal of the CM and of hemosiderin-stained surrounding brain tissue. Pathological assessments of the resected hippocampus were performed. Chronic intracranial electroencephalography (EEG) recordings were obtained in 6 patients. We performed perioperative neuropsychological assessments in all patients.

RESULTS

The seizure outcome was recorded as Engel class I in 17 patients (94.4%); Ia = 12 (66.7%) Ib = 2 (11.1%), Ic = 1 (5.6%), Id = 2 (11.1%), and class IIb in one patient (5.6%). Adding resection of the mesial temporal structures to lesionectomy did not alter the seizure outcome. Pathology of hippocampus revealed limited neuronal loss in CA4. Ictal onsets in the ipsilateral lateral cortex were detected in all 6 patients who underwent intracranial EEG. In 4 patients each, we also detected ictal onsets from the ipsilateral mesial temporal structures and from the contralateral temporal lobe. Postoperatively, in the patients where their CM was located in the language-dominant hemisphere (n = 10), the full-scale intelligence quotient (IQ) and the performance IQ increased (p < 0.05), whereas the verbal memory (WMS-R) deteriorated in two of 5 patients.

CONCLUSION

Excellent seizure outcomes were obtained even the lesionectomy alone. To confirm appropriate surgical strategy for lateral temporal CM with intractable epilepsy, further studies in large sample size are needed.

A predicted model for postoperative seizure outcomes after the surgical resection of supratentorial cavernous malformations

To explore a predicted model for postoperative seizure outcomes after the surgical resection of supratentorial cavernous malformations.This study was a retrospective review of consecutive patients with cerebral supratentorial cavernous malformations presenting with seizures. All patients underwent surgical resection of CCMs. Univariate and multivariate analyses were performed to determine the predictive value of the preoperative seizure frequency, seizure type, seizure duration, lesion location, lesion size, and the presence of residual hemosiderin.A total of 43 patients met the inclusion criteria. After a mean follow-up period of 40.95 months, 34 patients who were free from postoperative seizures were classified into Engel class I, and the remaining 9 patients were classified into Engel classes II-IV. A univariate analysis showed that the seizure frequency (χ = 13.440, P = 0.004) and seizure duration (χ = 5.145, P = 0.023) prior to surgery were associated with a worse postoperative seizure prognosis. Other covariates including age at onset, gender, a history of the medications taken, smoking status, family history, lesion characteristics, and the role of hemosiderin were not related to seizure outcomes. Logistic regression results demonstrated that the preoperative seizure frequency was an effective predictor (P = 0.004). The receiver operating characteristic curve indicated that area under the curve for the preoperative seizure frequency test was 0.833 (95% confidence interval 0.709-0.957, P = 0.002).The preoperative seizure frequency was a prognostic factor for postoperative seizure outcomes after surgical resection of supratentorial cavernous malformations. To obtain a favorable prognosis for CCM patients with preoperative seizures, early intervention might be a better choice.

[Amygdalohippocampectomy in treatment of epilepsy in patients with temporal lobe cavernomas]

BACKGROUND

In some cases, single-stage or delayed amygdalohippocampectomy (AHE) can be used for effective treatment of epileptic syndrome upon resection of temporal lobe cavernomas. The efficacy of AHE in treatment of temporal epilepsies is proved in general; however, the indications for surgery in patients with cavernomas are not developed.

OBJECTIVE

The study objective was to evaluate the efficacy and safety AHE in the treatment of epilepsy in patients with temporal lobe cavernomas and to define the indications for surgery.

MATERIAL AND METHODS

Of 14 patients with temporal lobe cavernomas, which manifested as epileptic seizures, 10 patients underwent selective AHE, and 4 patients underwent anteromedial temporal lobectomy. In 12 cases, AHE was performed simultaneously with cavernoma resection. Delayed AHE was carried out in 2 cases. All patients underwent preoperative MRI and EEG. Preoperative video-EEG monitoring was performed in 3 cases. The duration of postoperative follow-up was at least 1 year (mean follow-up was 3.3 years).

RESULTS

Improvement in the epileptic syndrome was observed in all patients. In the postoperative period, 7 patients had no seizures (Engel class IA); of them, 3 patients discontinued anticonvulsants. The surgery outcome depended on the disease duration. Significant postoperative complications in the form of reversible hemiparesis were observed in 1 case.

CONCLUSION

Amygdalohippocampectomy is highly efficient in treatment of severe forms of epilepsy in patients with temporal lobe cavernomas. In the case of long history of typical temporal seizures and pharmacoresistant epilepsy, AHE can be performed simultaneously with cavernoma resection.

Resective surgery for medically refractory epilepsy using intraoperative MRI and functional neuronavigation: the Erlangen experience of 415 patients

OBJECTIVE

Intraoperative overestimation of resection volume in epilepsy surgery is a well-known problem that can lead to an unfavorable seizure outcome. Intraoperative MRI (iMRI) combined with neuronavigation may help surgeons avoid this pitfall and facilitate visualization and targeting of sometimes ill-defined heterogeneous lesions or epileptogenic zones and may increase the number of complete resections and improve seizure outcome.

METHODS

To investigate this hypothesis, the authors conducted a retrospective clinical study of consecutive surgical procedures performed during a 10-year period for epilepsy in which they used neuronavigation combined with iMRI and functional imaging (functional MRI for speech and motor areas; diffusion tensor imaging for pyramidal, speech, and visual tracts; and magnetoencephalography and electrocorticography for spike detection). Altogether, there were 415 patients (192 female and 223 male, mean age 37.2 years; 41% left-sided lesions and 84.9% temporal epileptogenic zones). The mean preoperative duration of epilepsy was 17.5 years. The most common epilepsy-associated pathologies included hippocampal sclerosis (n = 146 [35.2%]), long-term epilepsy-associated tumor (LEAT) (n = 67 [16.1%]), cavernoma (n = 45 [10.8%]), focal cortical dysplasia (n = 31 [7.5%]), and epilepsy caused by scar tissue (n = 23 [5.5%]).

RESULTS

In 11.8% (n = 49) of the surgeries, an intraoperative second-look surgery (SLS) after incomplete resection verified by iMRI had to be performed. Of those incomplete resections, LEATs were involved most often (40.8% of intraoperative SLSs, 29.9% of patients with LEAT). In addition, 37.5% (6 of 16) of patients in the diffuse glioma group and 12.9% of the patients with focal cortical dysplasia underwent an SLS. Moreover, iMRI provided additional advantages during implantation of grid, strip, and depth electrodes and enabled intraoperative correction of electrode position in 13.0% (3 of 23) of the cases. Altogether, an excellent seizure outcome (Engel Class I) was found in 72.7% of the patients during a mean follow-up of 36 months (range 3 months to 10.8 years). The greatest likelihood of an Engel Class I outcome was found in patients with cavernoma (83.7%), hippocampal sclerosis (78.8%), and LEAT (75.8%). Operative revisions that resulted from infection occurred in 0.3% of the patients, from hematomas in 1.6%, and from hydrocephalus in 0.8%. Severe visual field defects were found in 5.2% of the patients, aphasia in 5.7%, and hemiparesis in 2.7%, and the total mortality rate was 0%.

CONCLUSIONS

Neuronavigation combined with iMRI was beneficial during surgical procedures for epilepsy and led to favorable seizure outcome with few specific complications. A significantly higher resection volume associated with a higher chance of favorable seizure outcome was found, especially in lesional epilepsy involving LEAT or diffuse glioma.

The Role of Hemosiderin Excision in Seizure Outcome in Cerebral Cavernous Malformation Surgery: A Systematic Review and Meta-Analysis

Background and Purpose

Whether the excision of hemosiderin surrounding cerebral cavernous malformations (CCMs) is necessary to achieve a seizure-free result has been the subject of debate. Here, we report a systematic review of related literature up to Jan 1, 2015 including 594 patients to assess the effect of hemosiderin excision on seizure outcome in patients with CCMs by meta-analysis.

Methods

Ten studies comparing extended hemosiderin excision with only lesion resection were identified by searching the English-language literature. Meta-analyses, subgroup analyses and sensitivity analysis were conducted to determine the association between hemosiderin excision and seizure outcome after surgery.

Results

Seizure outcome was significantly improved in the patients who underwent an extended excision of the surrounding hemosiderin (OR, 0.62; 95% CI: 0.42–0.91; P = 0.01). In subgroup analysis, studies from Asia (OR, 0.42; 95% CI: 0.25–0.71; P = 0.001), male-majority (female ratio < 50%) studies (OR, 0.56; 95% CI: 0.33–0.96; P = 0.04), low occurrence rate of multiple CCMs (OR, 0.37; 95% CI: 0.20–0.71; P = 0.003), cohort studies (OR, 0.44; 95% CI: 0.28–0.68; P = 0.78), longer duration of seizure symptoms (> 1 year) before surgery (OR, 0.43; 95% CI: 0.22–0.84; P = 0.01), lesion diameter > 2 cm (OR, 0.41; 95% CI: 0.19–0.87; P = 0.02) and short-term (< 3 years) follow-up (OR, 0.48; 95% CI: 0.29–0.80; P = 0.005) tended to correlate with a significantly favorable outcome.

Conclusion

Patients who underwent extended surrounding hemosiderin excision could exhibit significantly improved seizure outcomes compared to patients without hemosiderin excision. However, further well-designed prospective multiple-center RCT studies are still needed.

Microsurgical treatment and outcome of pediatric supratentorial cerebral cavernous malformation

OBJECTIVE

The purpose of this study was to investigate the clinical features and outcomes of pediatric cavernous malformation (CM) in the central nervous system.

METHODS

Twenty-nine pediatric patients with supratentorial CM underwent microsurgical excision. In selected cases, transparent tubular retractor system (TTRS) was used to reduce retraction injury and intraoperative neuromonitoring (IONM) was held to preserve functioning cortex. Patients' demographics and symptoms were reviewed and surgical outcomes were discussed.

RESULTS

THE MAIN INITIAL CLINICAL MANIFESTATIONS INCLUDED THE FOLLOWING : seizures (n=13, 45%), headache (n=7, 24%), focal neurological deficits (n=3, 10%), and an incidental finding (n=6, 21%). Overt hemorrhage was detected in 7 patients (24%). There were 19 children (66%) with a single CM and 10 (34%) children with multiple CMs. In 7 cases with deep-seated CM, we used a TTRS to minimize retraction. In 9 cases which location of CM was at eloquent area, IONM was taken during surgery. There was no major morbidity or mortality after surgery. In the 29 operated children, the overall long-term results were satisfactory : 25 (86%) patients had no signs or symptoms associated with CMs, 3 had controllable seizures, and 1 had mild weakness.

CONCLUSION

With the assistance of neuronavigation systems, intraoperative neuromonitoring, and TTRS, CMs could be targeted more accurately and excised more safely. Based on the satisfactory seizure outcome achieved, complete microsurgical excision in children is recommended for CMs presenting with seizures but removal of hemosiderin-stained areas seems to be unnecessary.

Longitudinal changes in seizure outcomes after resection of cerebral cavernous malformations in patients presenting with seizures: a long-term follow-up of 46 patients

BACKGROUND

Seizure is the most common presentation in patients with cerebral cavernous malformations (CCMs). Although many articles have documented seizure outcomes after resection of CCM, few have conducted long-term follow-ups; thus, the fluctuating seizure outcomes have been neglected. The purpose of this study is to describe long-term postoperative seizure outcomes in patients with CCM and to compare seizure outcomes between patients with sporadic seizures and those with chronic seizures.

METHODS

Forty-six patients with CCM presenting with seizures underwent surgery. The male-to-female ratio was 1:1, and the average age at initial seizure onset was 27.6 years. The mean preoperative seizure duration was 42.7 months. Patients were divided into two groups: a chronic group (N = 20) and a sporadic group (N = 26) according to seizure frequency and duration. The mean postoperative follow-up duration was 96.3 months, and the postoperative seizure outcomes were checked annually based upon Engel's classification.

RESULTS

After the first year of follow-up, 80.8 % of the sporadic group and 75.0 % of the chronic group were evaluated as Engel class I. These rates increased to 100.0 % and 90.0 %, respectively, at the eighth year of follow-up. Overall, 29 (63.0 %) of the 46 patients experienced changes in seizure outcomes over the follow-up period. Despite their delayed improvements, the chronic group showed less favorable outcomes throughout follow-up (p = 0.025).

CONCLUSIONS

Long-term follow-up is indispensable for accurately assessing postoperative seizure outcomes because these outcomes change continuously. We recommend earlier surgery to achieve seizure-free status in patients with CCM. However, even in the chronic group, surgery is recommended, considering the overall delayed improvement.

Cerebral cavernous malformations in the setting of focal epilepsies: pathological findings, clinical characteristics, and surgical treatment principles

Cavernous cerebral malformations (CCMs) are a well-defined epilepsy-associated pathology. They represent lesions/conglomerates of abnormally configured vessels leading to seizures either as a result of physiological changes affecting the cerebral cortex immediately surrounding the CCM (an epileptogenic mechanism that is relevant for both temporal and extratemporal lesions), or as a result of promoting epileptogenicity in remote but anatomo-functionally connected brain regions (a mechanism that is particularly relevant for temporal lobe lesions). This review details the pathological findings in CCMs and discusses the mechanisms of epileptogenicity in this context. The bulk of the review will focus on therapeutic strategies. Medical therapy using antiepileptic drugs is recommended as a first-line therapy, but surgical removal of the CCM with the surrounding cortex should be pursued if seizures prove to be drug resistant. Early timing of the resection and complete removal of any associated epileptic pathology are critical for best outcomes. In addition to reviewing the available data from prior series, we present original research from two specialized epilepsy centers targeted at answering particularly pressing clinical questions mainly related to the ideal timing and extent of surgery. Further research is needed to define the best surgical strategies in patients with temporal lobe CCMs and structurally normal hippocampi.

Rates and predictors of seizure freedom in resective epilepsy surgery: an update

Epilepsy is a debilitating neurological disorder affecting approximately 1 % of the world's population. Drug-resistant focal epilepsies are potentially surgically remediable. Although epilepsy surgery is dramatically underutilized among medically refractory patients, there is an expanding collection of evidence supporting its efficacy which may soon compel a paradigm shift. Of note is that a recent randomized controlled trial demonstrated that early resection leads to considerably better seizure outcomes than continued medical therapy in patients with pharmacoresistant temporal lobe epilepsy. In the present review, we provide a timely update of seizure freedom rates and predictors in resective epilepsy surgery, organized by the distinct pathological entities most commonly observed. Class I evidence, meta-analyses, and individual observational case series are considered, including the experiences of both our institution and others. Overall, resective epilepsy surgery leads to seizure freedom in approximately two thirds of patients with intractable temporal lobe epilepsy and about one half of individuals with focal neocortical epilepsy, although only the former observation is supported by class I evidence. Two common modifiable predictors of postoperative seizure freedom are early operative intervention and, in the case of a discrete lesion, gross total resection. Evidence-based practice guidelines recommend that epilepsy patients who continue to have seizures after trialing two or more medication regimens should be referred to a comprehensive epilepsy center for multidisciplinary evaluation, including surgical consideration.

Surgical Resection Can Be Successful in a Large Fraction of Patients With Drug-Resistant Epilepsy Associated With Multiple Cerebral Cavernous Malformations

BACKGROUND:

Multiple cerebral cavernous malformations (mCCMs) are known as potentially epileptogenic lesions. Treatment might be multimodal. Management of patients with mCCMs and epilepsy is challenging.

OBJECTIVE:

To evaluate (1) algorhythmic therapeutic sequences in patients with epilepsy associated to mCCMs, (2) whether there are predictive parameters to anticipate the development of drug-resistant epilepsy, and (3) seizure after epilepsy surgery compared to conservatively-treated drug-resistant patients.

METHODS:

All inpatients and outpatients with epilepsy associated to mCCMs from 1990 to 2010 and follow-up &gt;12 months available were retrospectively analyzed.

RESULTS:

Twenty-three patients matched inclusion criteria. Epilepsy became drug-resistant in 18/23 (78%) patients. No predictors were found for development of drug-resistant epilepsy. Median follow-up for both groups was 7.8 years. Nine patients did not qualify for surgical therapy and were treated conservatively. One patient of this cohort (11%) was seizure-free (International League Against Epilepsy [ILAE] class 1). Surgical treatment was performed in 9 patients; 7/9 (78%) of these patients were seizure-free (ILAE class 1) after epilepsy surgery for at least 12 months compared with 1/9 patients in the non-operated group. In 7/9 cases (78%) the largest CCM was resected. In 8/9 (89%) not all CCMs were resected.

CONCLUSION:

After initial diagnosis of epilepsy associated to mCCMs, a primary conservative approach is reasonable. Surgical treatment can be successful in a large fraction of cases with drug-resistant epilepsy where an epileptogenic lesion is identified. Cases where surgery is not undertaken are likely to remain intractable.

Long-term seizure outcomes following resection of supratentorial cavernous malformations

OBJECTIVE

Symptomatic supratentorial cavernous malformations may present with seizure, headache, neurological deficit, or a combination thereof. Factors that contribute to treatment algorithms commonly include patient age, lesion size and location, lesion multiplicity, hemorrhage history, and the ability to control seizure activity with medication. A better appreciation of the impact of patient and lesion characteristics on post-operative seizure control may provide insight into management strategies. To determine long-term seizure outcomes following surgical resection of supratentorial cavernous malformations, the predictive value of characteristics including seizure duration and number, presence of generalized seizures, and lesion multiplicity and size on seizure control rate was evaluated.

METHODS

We performed a single institution retrospective review of consecutive patients with supratentorial cavernous malformations presenting with at least one seizure between 1995 and 2008. Univariate and multivariate analyses were used to determine the influence of patient and lesion characteristics on postoperative seizure control.

RESULTS

Fifty-six patients met inclusion criteria. Mean follow-up duration was 87.9 months. At last follow-up there were 46 patients (82.1%) that were free from impairing seizures (Engel Class 1). Ten patients (17.9%) were classified as Engel Class 2-4. Univariate analysis demonstrated that only the presence of multiple cavernomas was associated with worse post-operative seizure outcome (p=0.006). Multivariate analysis demonstrated that multiple cavernomas remained a significant predictor for development of worse seizure outcome controlling for number and duration of seizures prior to operation, presence of generalized tonic-clonic seizures, and size (odds ratio, 0.17; 95% confidence interval, 0.03, 0.99).

CONCLUSION

Resection of supratentorial cavernomas is associated with a high rate of postoperative seizure freedom. The presence of multiple cavernomas is predictive of seizure persistence following surgery.

Technical, Anatomical, and Functional Study after Removal of a Symptomatic Cavernous Angioma Located in Deep Wernicke's Territories with Cortico-Subcortical Awake Mapping

Introduction. The subcortical region underneath Wernicke's area (WA) is a critical crossing of the eloquent language pathways involved in all semantic, phonological, syntactic, and working memory elaboration. We report the resection of a CA located underneath the dominant WA discussing the functional and anatomical evidence provided by fMRI, dissections with Klingler's technique, and intraoperative mapping during awake surgery. Case Report. A 64-year-old right-handed female affected by daily complex focal seizures underwent f-MRI, showing language activations in the middle and inferior temporal gyri and an unusual free entry zone in the “classical” WA. The cortical intraoperative mapping partially confirmed the f-MRI results, and we approached the lesion directly through WA. Subcortical DES allowed the identification of the eloquent language pathways and the radical resection of the perilesional gliotic rim. The patient did not report deficits and she is seizures and drug free after 1-year surgery. Discussion. Cortical DES demonstrated the variability of the eloquent areas within the cortex of the dominant temporal lobe. The subcortical DES confirmed the crucial role in language elaboration and the anatomical course of the bundles underneath WA. Conclusions. Awake surgery with DES represents a reliable and dynamic technique also for safer and functional-customized resection of CAs.

The outlook for adults with epileptic seizure(s) associated with cerebral cavernous malformations or arteriovenous malformations

Cerebral cavernous malformations (CCMs) and arteriovenous malformations (AVMs) are common: their asymptomatic prevalence on brain magnetic resonance imaging (MRI) is 1 in 625 and 1 in 2,000, respectively. The risk of epileptic seizure(s) for people with AVMs and CCMs affects their domestic, social, and professional lives, and may influence their decisions about treatment. This article summarizes the seizure risks for people with AVMs and CCMs, gleaned from published original articles indexed in OVID Medline and Embase before 1 January 2012. In the absence of prior intracranial hemorrhage and nonhemorrhagic focal neurologic deficit, a population-based study in Scotland, United Kingdom, found that the 5-year risks of first seizure were 8% for AVM and 4% for CCM; presentation with intracranial hemorrhage or focal neurologic deficit raised this risk for AVM (23%) but not for CCM (6%). Features associated with the occurrence of epileptic seizures for CCM are lesion multiplicity and cortical CCM location, whereas for AVM the most consistently reported associations are younger age, temporal location, cortical involvement, and nidus diameter >3 cm. In the absence of prior intracranial hemorrhage and nonhemorrhagic focal neurologic deficit, the 5-year risk of developing epilepsy following a first seizure is 58% for AVM and 94% for CCM, though there is no difference in the chance of achieving 2-year seizure freedom in this time frame (45% AVM vs. 47% CCM). Observational case series describe encouraging differences in seizure frequency before and after AVM and CCM treatment, but the shortage of studies demonstrating dramatic effects in comparison to concurrent control groups justifies the need for more controlled studies, ideally with randomized treatment allocation when the benefits of AVM or CCM treatment are uncertain.

Surgical management of cavernous malformations presenting with drug-resistant epilepsy

Cerebral cavernous malformations (CMs) are dynamic lesions characterized by continuous size changes and repeated bleeding. When involving cortical tissue, CMs pose a significant risk for the development of drug-resistant epilepsy, which is thought to be result of an altered neuronal network caused by the lesion itself and its blood degradation products. Preoperative evaluation should comprise a complete seizure history, neurological examination, epilepsy-oriented MRI, EEG, video-EEG, completed with SPECT, PET, functional MRI, and/or invasive monitoring as needed. Radiosurgery shows variable rates of seizure freedom and a high incidence of complications, thus microsurgical resection remains the optimal treatment for CMs presenting with drug-resistant epilepsy. Two thirds of patients reach Engel I class at 3-year follow-up, regardless of lobar location. Those with secondarily generalized seizures, a higher seizure frequency, and generalized abnormalities on preoperative or postoperative EEG, show poorer outcomes, while factors such as gender, duration of epilepsy, lesion size, age, bleeding at the time of surgery, do not correlate consistently with seizure outcome. Electrocorticography and a meticulous removal of all cortical hemosiderin - beyond pure lesionectomy - reduce the risk of symptomatic recurrences.

Predictors of seizure freedom in the surgical treatment of supratentorial cavernous malformations

OBJECT

Seizures are the most common presenting symptom of supratentorial cerebral cavernous malformations (CCMs) and progress to medically refractory epilepsy in 40% of patients. Predictors of seizure freedom in the resection of CCMs are incompletely understood.

METHODS

The authors systematically reviewed the published literature on seizure freedom following the resection of supratentorial CCMs in patients presenting with seizures. Seizure outcomes were stratified across 12 potential prognostic variables. A total of 1226 patients with supratentorial CCMs causing seizures were identified across 31 predominantly retrospective studies; 361 patients had medically refractory epilepsy.

RESULTS

Seventy-five percent of the patients were seizure free after microsurgical lesion removal, whereas 25% continued to have seizures. All patients had had preoperative seizures and > 6 months of postoperative follow-up. Modifiable predictors of postoperative seizure freedom included gross-total resection (OR 36.6, 95% CI 8.5-157.5) and surgery within 1 year of symptom onset (OR 1.83, 95% CI 1.30-2.58). Additional prognostic indicators of a favorable outcome were a CCM size < 1.5 cm (OR 15.4, 95% CI 5.2-45.4), the absence of multiple CCMs (OR 2.02, 95% CI 1.13-3.60), medically controlled seizures (OR 2.38, 95% CI 1.29-4.39), and the lack of secondarily generalized seizures (OR 3.33, 95% CI 2.09-5.30). Other factors, including extended resection of the hemosiderin ring, were not significantly predictive.

CONCLUSIONS

In the surgical treatment of supratentorial CCMs, gross-total resection and early operative intervention may improve seizure outcome. While surgery should not be considered the first-line treatment for CCM-related epilepsy, it is important to understand the variables associated with seizure freedom in CCM resection given the considerable morbidity and diminished quality of life associated with epilepsy.

Microsurgical treatment of temporal lobe cavernomas

BACKGROUND

Cavernomas of the temporal lobe occur in 10-20% of patients with cerebral cavernomas. They frequently cause epileptic seizures, some of which tend to become refractory to medical therapy. Surgical removal of safely achievable symptomatic lesions has been frequently consistent with good long-term outcome. In the present study, a postoperative outcome is assessed.

METHODS

Of our 360 consecutive patients with cerebral cavernomas, 53 (15%) had a single cavernoma in the temporal lobe. Forty-nine patients were treated surgically and were included in the study. All data were analyzed retrospectively. The cavernomas were allocated into three groups based on the temporal lobe site: medial, anterolateral, and posterolateral. To collect follow-up data, all available patients were interviewed by phone. Seizure outcome was assessed using the Engel classification and general outcome using the Glasgow Outcome Scale (GOS).

RESULTS

Patients' median age at presentation was 37 (range, 7-64) years, with a female/male ratio of 2.5:1. Epileptic seizures occurred in 40 patients (82%). Median duration of seizures preoperatively was 3 (range, 0.1-23) years. In addition, four patients (10%) had memory disorder. Three patients without history of seizures (6%) complained of headache and two (4%) had memory problems. Three patients (6%) had an incidental cavernoma. Hemorrhage occurred in nine patients (18%) preoperatively. Median postoperative follow-up time was 6 (range, 0.2-26) years. Favorable seizure outcome (Engel class I and II) was registered in 35 patients (90%). Ten patients (25%) who had only a single seizure before surgery were seizure free during postoperative follow-up. Good general outcome (GOS, 4.5) was detected in 46 patients (96%). Two patients (4%) developed a new mild memory deficit after surgery, and in two patients existing memory deficits worsened.

CONCLUSIONS

Microsurgical removal of temporal lobe cavernomas is a safe and effective method to improve seizure outcome in patients with medically intractable epilepsy and to prevent deterioration caused by hemorrhage.

Cerebral cavernous malformations and intractable epilepsy: the limited usefulness of current literature

BACKGROUND

Cerebral cavernous malformations (CCM) are known to be highly epileptogenic lesions. A number of studies on CCM surgery deal with CCM-associated seizures and/or epilepsy. In order to counsel patients with CCM-associated epilepsy, clear results from such studies would be highly useful. This study reviews the current literature with the aim to assess its usefulness for presurgical decision-making with emphasis on differentiating outcomes in different epilepsy types.

METHODS

A systematic Medline search identified 27 studies between 1991 and 2009 through the keywords "cavernomas, cavernous, hemangioma, AND epilepsy, AND surgery". They were analysed with regard to clarity of definition of epilepsy subtypes, precision of definition of drug-resistant epilepsy, information on surgical procedure and presurgical workup, seizure outcome and length of follow-up.

RESULTS

Twenty studies included only surgically treated patients. Three types of epilepsy were defined: drug-resistant epilepsy, epilepsy or single/sporadic seizures. In 12 of 27 studies, at least one of these categories remained unclear. The classic definition of drug-resistant epilepsy was not used in the vast majority of studies, with many groups using their own definition. In 30%, the surgical procedure was not described precisely, although 52% of studies used a differentiated preoperative evaluation. Seizure outcome was described using a widely accepted classification in only 48% of series, and in over half of the studies outcome results contained cases with insufficient length of follow-up.

CONCLUSIONS

A large proportion of recent studies on surgery for CCM-associated epilepsy are not using criteria and definitions for the classification of epilepsy and outcome that are commonly used by epileptologists or epilepsy surgeons. This results in the limited usefulness of a large part of the literature for the purpose of preoperative counselling a patient with CCM-associated epilepsy.

Primary epileptogenic unruptured intracranial aneurysms: incidence and effect of treatment on epilepsy

BACKGROUND

Seizures as the unique initial manifestation of unruptured intracranial aneurysms have rarely been documented and not systematically described until now.

OBJECTIVE

The purpose of this large retrospective analysis was to focus on the incidence of primary epileptogenic aneurysms and the influence of treatment on epilepsy.

METHODS

Within a 16-year period, 347 unruptured aneurysms were surgically treated at centers in Munich (1992-2002) and Düsseldorf (2003-2008), Germany. Of this patient population, 9 patients presented exclusively with epileptic seizures or epileptic equivalents. In 3 of them, a high-lying internal carotid artery aneurysm was diagnosed that was buried in the parahippocampal gyrus. In 4 patients, a middle cerebral artery aneurysm also created contact with the mediotemporal lobe adjacent to the parahippocampal gyrus. An anterior communicating artery aneurysm and a pericallosal artery aneurysm were diagnosed in 2 additional patients. Two patients with a middle cerebral artery aneurysm were initially incompletely occluded with Guglielmi detachable coils and continued to have epilepsy after the intervention. In all but 1 patient, the aneurysms were clipped and completely removed.

RESULTS

In all 8 patients operated on, there was no sign of hemorrhage intraoperatively but cortical gliosis was seen around the dome of the aneurysm. In all cases, the aneurysm and the surrounding gliosis, if existent, were surgically removed. Freedom from seizures without medication resulted for all patients after microsurgery.

DISCUSSION

Seizures as a presenting symptom of unruptured intracranial aneurysms are rare. There seems to be a preponderance of aneurysms anatomically related to the temporomedial region. Elimination of the aneurysm and perifocal gliosis provides the possibility of a cure for the epilepsy.

Cerebral cavernous malformations as a disease of vascular permeability: from bench to bedside with caution

Tremendous insight into the molecular and genetic pathogenesis of cerebral cavernous malformations (CCMs) has been gained over the past 2 decades. This includes the identification of 3 distinct genes involved in familial CCMs. Still, a number of unanswered questions regarding the process from gene mutation to vascular malformation remain. It is becoming more evident that the disruption of interendothelial junctions and ensuing vascular hyperpermeability play a principal role. The purpose of this review is to summarize the current understanding of CCM genes, associated proteins, and functional pathways. Promising molecular and genetic therapies targeted at identified molecular aberrations are discussed as well.

Epileptogenic temporal cavernous malformations: operative strategies and postoperative seizure outcomes

Operative treatment of epileptogenic cavernous malformations (CM) continues under debate. Most studies focus on surgery for supratentorial CM in general. For temporal lobe CM, surgical decision-making concerns in particular whether to perform lesionectomy alone or the additional excision of mesial temporal structures. The purpose of this case series was to evaluate operative strategies used to treat epileptogenic temporal CM and to report resultant postoperative seizure outcomes. Twelve consecutive cases of patients with medically intractable epilepsy who underwent operation for temporal CM between 1996 and 2006 were retrospectively reviewed. When the temporal CM directly invaded the hippocampus or amygdala, the affected structures were resected in addition to the lesion; when the CM was located in the superficial temporal cortex, and there was no radiographic evidence of hippocampal sclerosis, lesionectomy alone was done; with CM located between the superficial temporal cortex and the mesial temporal region, other factors were considered in decision-making, such as lesion proximity to the deep mesiotemporal structures and preoperative epilepsy duration. For six of the twelve patients, extended lesionectomy (EL) alone was done; for the other six, tailored anteromedial temporal resection with hippocampectomy and/or amygdalectomy was performed in addition to EL. Postoperatively, 11 patients - all with preoperative VEM demonstrating electroclinical seizure patterns concordant with lesion location - were seizure-free. We conclude that epileptogenic temporal CM are surgically remediable, when approached with the above operative strategies and presurgical VEM. On the basis of these postoperative seizure control results, we recommend consideration of concurrent resection of mesial temporal structures with EL for certain temporal CM.

Seizure characteristics and control after microsurgical resection of supratentorial cerebral cavernous malformations

OBJECTIVE

The optimal management of seizures associated with cerebral cavernous malformations (CCMs) is unclear. The aim of this study was to determine the efficacy of surgery in the management of CCM-associated seizures.

METHODS

We conducted a retrospective review with follow-up of 164 patients who underwent microsurgical resection of supratentorial CCMs. Clinical and radiographic data were collected and then analyzed to determine predictors of developing epilepsy and predictors of postoperative seizure control after microsurgical resection.

RESULTS

Of the patients, 61.5% presented with seizures, and 34.7% had clinically defined epilepsy. The development of epilepsy was associated with CCMs located in the temporal lobe and the absence of symptomatic hemorrhage. After microsurgical resection in 44 patients with intractable epilepsy, 72.7% were completely seizure-free (Engel class 1), 11.4% had rare seizures (Engel class 2), 4.5% had meaningful improvement (Engel class 3), and 11.4% had no improvement (Engel class 4). Predictors of complete seizure freedom were gross total resection, smaller CCMs, and the absence of secondary generalized seizures (94% of patients were seizure-free with all 3 predictors).

CONCLUSION

Surgery is a safe and effective treatment for seizures associated with CCMs.

Suicide in people with epilepsy: how great is the risk?

PURPOSE

Suicide is more common in populations with epilepsy, but estimates vary concerning the magnitude of the risk. We aimed to estimate the risk using meta-analysis.

METHODS

A literature search identified 74 articles (76 cohorts of people with epilepsy) in whom the number of deaths by suicide in people with epilepsy and the number of person-years at risk could be estimated. Standardized mortality ratios (SMRs) with 95% confidence intervals (CIs) were calculated for each cohort, for groups of cohorts, and for the total population.

RESULTS

The overall SMR was 3.3 (95% CI 2.8-3.7) based on 190 observed deaths by suicide compared with 58.4 expected. The SMR was significantly increased in people with incident or newly diagnosed epilepsy in the community (SMR 2.1), in populations with mixed prevalence and incidence cases (SMR 3.6), in those with prevalent epilepsy (SMR 4.8), in people in institutions (SMR 4.6), in people seen in tertiary care clinics (SMR 2.28), in people with temporal lobe epilepsy (SMR 6.6), in those following temporal lobe excision (SMR 13.9), and following other forms of epilepsy surgery (SMR 6.4). The SMR was significantly low overall in two community-based studies of people with epilepsy and developmental disability.

DISCUSSION

We confirm that the risk of suicide is increased in most populations of people with epilepsy. Psychiatric comorbidity has been demonstrated to be a risk factor for suicide in the general population and in people with epilepsy, and such comorbidity should thus be identified and treated.

Long-term seizure control after resection of supratentorial cavernomas: a retrospective single-center study in 53 patients

OBJECTIVE

The goal of this study was to examine the long-term outcomes of 53 epilepsy patients who were surgically treated for supratentorial cavernomas in a single-center study and to assess both the duration of epilepsy and the resection of the hemosiderin rim for their prognostic relevance during extended follow-up.

METHODS

Fifty-three patients underwent microsurgical resection of radiologically diagnosed supratentorial cavernomas. For the outcome analysis, they were divided into 2 groups: Group A (33 patients) with a preoperative duration of epilepsy of less than 2 years, and Group B (20 patients) with a preoperative duration of epilepsy of 2 years or more. The natural history of the cavernomas, localization and size of the lesions, use of antiepileptic drugs, surgery timing, and technique (removal or not of the surrounding gliosis) were evaluated retrospectively. The outcome of epilepsy was based on Engel's classification and the International League Against Epilepsy classification.

RESULTS

After a mean follow-up period of 8.1 years, 45 (84.9%) of the 53 patients were free from disabling seizures (Engel Class I), including 37 patients (69.8%) who were completely free of postoperative seizures (Engel Class IA); 43 patients (81.1%) were categorized as International League Against Epilepsy Class 1. Outcome was statistically significantly improved in the patient subgroup of our study in which patients underwent a resection of the surrounding gliosis after a preoperative duration of epilepsy of less than 2 years (Group A). There was no mortality, and only minor postoperative neurological deficits occurred in 7.5% of patients.

CONCLUSION

In a long-term follow-up period, 84.9% of the patients in the study could be evaluated as Engel Class I. The analysis of outcome showed that patients benefited significantly from early surgery and excision of the hemosiderin rim.

Phase I trial: safety and feasibility of intracranial electroencephalography using hybrid subdural electrodes containing macro- and microelectrode arrays

OBJECT

Cerebral cortex electrophysiology is poorly sampled using standard, low spatial resolution clinical intracranial electrodes. Adding microelectrode arrays to the standard clinical macroelectrode arrays increases the spatial resolution and may ultimately improve the clinical utility of intracranial electroencephalography (iEEG). However, the safety of hybrid electrode systems containing standard clinical macroelectrode and microelectrode arrays is not yet known. The authors report on their preliminary experience in 24 patients who underwent implantation of hybrid electrodes.

METHODS

In this study, 24 consecutive patients underwent long-term iEEG monitoring with implanted hybrid depth and subdural grid and strip electrodes; both clinical macroelectrodes and research microelectrodes were used. The patients included 18 women and 6 men with an average age of 35 +/- 12 years (range 21-65). The mean hospital stay was 11 +/- 4 days (range 5-20), with mean duration of implantation 7.0 +/- 3.2 days (range 3-15). Data from the 198 consecutive craniotomies for standard clinical subdural grid insertion (prior to surgery in the 24 patients described here) were used for comparison to investigate the relative risk of complications.

RESULTS

Focal seizure identification and subsequent resection was performed in 20 patients. One patient underwent a subsequent operation after neurological deterioration secondary to cerebral swelling and a 5-mm subdural hematoma. There were no infections. The overall complication rate was 4.2% (only 1 patient had a complication), which did not significantly differ from the complication rate previously reported by the authors of 6.6% when standard subdural and depth intracranial electrodes were used. There were no deaths or permanent neurological deficits related to electrode implantation.

CONCLUSIONS

The authors demonstrate the use of hybrid subdural strip and grid electrodes containing high-density microwire arrays and standard clinical macroelectrodes. Hybrid electrodes provide high spatial resolution electrophysiology of the neocortex that is impossible with standard clinical iEEG. In this initial study in 24 patients, the complication rate is acceptable, and there does not appear to be increased risk associated with the use of hybrid electrodes compared with standard subdural and depth iEEG electrodes. More research is required to show whether hybrid electrode recordings will improve localization of epileptic foci and tracking the generation of neocortical seizures.

Supratentorial cavernous angiomas presenting with seizures: surgical outcomes in 60 consecutive patients

The aim of this study is to determine surgical outcomes and factors affecting seizure outcomes in patients who harbor supratentorial cavernous angiomas presenting with seizures. Sixty patients were classified into the intractable epilepsy group (n=22) and the sporadic seizure group (n=38) and then managed differently in accordance with our guidelines. Patients exhibiting sporadic seizures were treated by lesionectomy, except for patients harboring mesial temporal lesions. We performed lesionectomy, extended lesionectomy, standard temporal lobectomy and tailored resection on 33, 9, 9 and 9 patients, respectively. Finally, 72.7% (16/22) of patients with intractable epilepsy and 89.5% (34/38) of patients with sporadic seizures achieved Engel Class I outcomes. A long duration of illness was somewhat related to a poor outcome in patients with intractable epilepsy, yet this was not true of patients with sporadic seizures. Other factors which included age at onset, size of the lesions and locations were not related to seizure outcomes. The role of residual hemosiderin is yet to be discovered. A lesionectomy alone can be considered a reasonable approach for those patients who exhibit sporadic seizures and have an extra-temporal or neo-temporal lesion. In patients with intractable epilepsy and/or mesial temporal lesions, a more invasive approach could achieve the better seizure outcome.

Treatment of Epileptogenic Cavernomas: Surgery versus Radiosurgery

BACKGROUND

Epilepsy is the most common symptom of cavernoma. Although microsurgery is the mainstay treatment for epileptogenic cavernoma, this procedure may cause severe complications for some lesions. This report aimed to study if linear accelerator (LINAC) radiosurgery was an alternative treatment modality for epileptogenic cavernoma.

METHODS

In this retrospective study, 29 patients were diagnosed with epileptogenic cavernomas from September 1995 to March 2005. Fifteen patients were treated with surgical excision and 14 with LINAC radiosurgery. The evaluation of epilepsy control was according to Engel's classification.

RESULTS

In the surgical group, 13 (86.7%) of 15 patients had a class I seizure-free outcome. In the radiosurgery group, class I control was achieved in 9 (64.3%) of 14 patients. However, there was no significant difference in the results of treatment between the two groups.

CONCLUSIONS

LINAC radiosurgery is an alternative treatment for epileptogenic cavernomas, especially when the lesions are located in the central regions or eloquent areas of the brain.

Prediction of postoperative outcome with special respect to removal of hemosiderin fringe: A study in patients with cavernous haemangiomas associated with symptomatic epilepsy

PURPOSE

In this study 30 patients with symptomatic epilepsy caused by cavernomas were investigated in a postoperative follow up study to assess predictors for postoperative outcome with respect to indications, time and approach of surgery.

METHODS

Thirty patients with cavernomas refractory to medical treatment were scheduled for surgery based on the findings of high-resolution MR imaging and intensive EEG-video monitoring. Postoperative outcome of epilepsy was assessed by follow-up examinations based on the basis of classification by Engel and the International League against epilepsy (ILAE).

RESULTS

The following variables were associated with good postoperative outcome: (1) complete resection of hemosiderin fringe surrounding the cavernoma was correlated to less postoperative seizure frequency versus incomplete resection of the hemosiderin fringe according to the outcome protocol of ILAE. (2) Lower duration of epilepsy at the time of operation was correlated to a better postoperative outcome with a benefit for recovery. (3) Absence of hemorrhage before surgery and unifocal seizure onset was a predictor for a favorable outcome, whereas bilateral or multifocal seizure onset zones showed poorer postoperative outcomes. (4) In patients with dual pathology (hippocampal sclerosis in addition to a cavernoma), lesionectomy plus hippocampectomy as opposed to lesionectomy only, had a better outcome than single lesionectomy.

CONCLUSION

Postoperative outcome in patients with cavernomas should be the topic of further prospective multicenter studies involving a large number of patients. In addition to the ideal operation time and handling of dual pathology the role of extended resection including perilesional hemorrhages should be taken into account.

Seizure Outcome after Resection of Supratentorial Cavernous Malformations: A Study of 168 Patients

PURPOSE

The optimal management of cerebral cavernous malformations (CCMs) with epileptic seizures is still a matter of debate. The aim of our study was to examine seizure outcome in the largest published series of surgically treated patients with epilepsy due to a supratentorial CCM, and to define predictors for good surgical outcome.

METHODS

We retrospectively studied 168 consecutive patients with a single supratentorial CCM and symptomatic epilepsy in a multicenter study. Pre- and postoperative clinical examinations, age at epilepsy onset, age at operation, type of symptoms due to the CCM (seizures, headache, hemorrhage, focal deficits), type and frequency of epileptic seizures, and the localization and size of the CCM were assessed. Seizure outcome was determined in the first, second, and third postoperative years.

RESULTS

The CCM was completely resected in all patients. More than two thirds of the patients were classified as seizure free in the first 3 postoperative years. Predictors for good seizure outcome were age older than 30 years at the time of surgery, mesiotemporal CCM localization, CCM size <1.5 cm, and the absence of secondarily generalized seizures. No mortality occurred in our series, but only mild postoperative neurologic deficits in 12 (7%) patients.

CONCLUSIONS

Considering the natural history of CCMs, the favorable neurologic and seizure outcome, surgical resection of CCMs should be considered in all patients with supratentorial CCMs and concomitant epilepsy, irrespective of the presence or absence of predictors for a favorable seizure outcome.

Drug-resistant temporal lobe epilepsy due to cavernous malformations

Object

Supratentorial cavernous angiomas may be associated with drug-resistant focal epilepsy. Surgical removal of the malformation may result in seizure control in a number of patients, although in most studies a long history and high frequency of attacks have been recognized as indicators of unfavorable seizure outcome. In the literature, there are no clear indications regarding the optimal diagnostic presurgical workup and the surgical strategy for this particular subgroup of patients with symptomatic epilepsy. In this paper the authors focus on the preoperative workup and the surgical management of the disease in eight consecutive patients undergoing surgery for drug-resistant temporal lobe epilepsy (TLE) due to cavernous malformations (CMs), and the relevant literature on this issue is also reviewed.

Methods

Preoperatively, all patients were assessed using a noninvasive protocol aimed at localizing the epileptogenic zone on the basis of anatomical, electrical, and clinical criteria. The presurgical assessment yielded an indication for lesionectomy in two cases, lesionectomy plus anteromesial temporal lobectomy in four cases, and lesionectomy plus extended temporal lobectomy in two cases. At follow-up examinations, seizure, neuropsychological, and psychiatric outcomes were all evaluated. Seven patients were categorized in Engel Class IA (seizure free), and one was categorized in Engel Class IB (occasional auras only). No adverse effects on neuropsychological or psychosocial functioning were observed.

Conclusions

Epilepsy surgery can be performed with excellent results in patients with intractable TLE caused by CMs. Noninvasive presurgical evaluation of these patients may enable a tailored approach, providing complete seizure relief in most cases.

Cerebral cavernous malformations and epilepsy

✓Seizures and epilepsy are frequent clinical manifestations of cerebral cavernous malformations (CCMs) and represent the most common symptomatic presentation of supratentorial lesions. Clinicians often diagnose CCMs in patients after a first seizure, or in some cases after obtaining neuroimaging studies in patients suffering from chronic epilepsy previously thought to be idiopathic. In some cases, the lesion is clinically significant solely because of its epileptogenicity, but in others there may be concern about potential hemorrhage or focal neurological deficits from a similar lesion.

The authors present current pathophysiological concepts related to epilepsy associated with CCMs. They discuss the spectrum of seizure disorders associated with these lesions and review the natural history, prognosis, and options for therapeutic intervention.

Seizure Outcome after Resection of Cavernous Malformations Is Better When Surrounding Hemosiderin-stained Brain Also Is Removed

PURPOSE

Considering the epileptogenic effect of cavernoma-surrounding hemosiderin, assumptions are made that resection only of the cavernoma itself may not be sufficient as treatment of symptomatic epilepsy in patients with cavernous malformations. The purpose of this study was to test the hypothesis whether seizure outcome after removal of cavernous malformations may be related to the extent of resection of surrounding hemosiderin-stained brain tissue.

METHODS

In this retrospective study, 31 consecutive patients with pharmacotherapy-refractory epilepsy due to a cavernous malformation were included. In all patients, cavernomas were resected, and all patients underwent pre- and postoperative magnetic resonance imaging (MRI). We grouped patients according to MRI findings (hemosiderin completely removed versus not/partially removed) and compared seizure outcome (as assessed by the Engel Outcome Classification score) between the two groups.

RESULTS

Three years after resection of cavernomas, patients in whom hemosiderin-stained brain tissue had been removed completely had a better chance for a favorable long-term seizure outcome compared with those with detectable postoperative hemosiderin (p=0.037).

CONCLUSIONS

Our study suggests that complete removal of cavernoma-surrounding hemosiderin-stained brain tissue may improve epileptic outcome after resection of cavernous malformations.

Surgical resection of cavernous angiomas located in eloquent areas--clinical research

BACKGROUND

In patients with lesions at the eloquent areas, the aim of surgical interventions should be a more radical removal of the lesions with preservation of brain function. In this retrospective study, our techniques for localizing lesion and the postoperative results of 26 patients with cavernous angiomas (CA) located at the eloquent areas are summarized.

METHOD

The MR based 3D-rendering images were reconstructed from the 2D MR images by using a computerized program. These images were obtained in all patients for the localization of their lesion. Following craniotomy, to verify the actual location of lesions, we compared the 3D-image to the exposed cortical surface. Simultaneously, intraoperative ultrasonogram (IOUS) was used for the accurate localization of the lesion. In order to minimize the damage to the eloquent area, the minimal corticotomy was planned at the margin of the sulcus nearest to the lesion.

FINDINGS

An accurate localization of the lesion was possible in all 26 patients and the eloquent areas near the lesions were identified on the operation field. Complete removal of the CAs was done in all cases. One patient developed temporary monoparesis postoperatively, but the patient fully recovered in a month. Fourteen patients presented with preoperative seizures, and all patients had excellent seizure outcome after their surgery. The mean duration of the follow-up period was 27 months.

CONCLUSIONS

We could localize the lesion accurately using MRI 3D-rendering images and IOUS during the operation for CA. We planned minimal corticotomy to the lesion and we completely removed the lesion without causing any additional neurological deficit. Although CA can be located in eloquent areas, surgical removal of these lesions is a safe and effective treatment option for lowering the risk of developing symptoms and controlling the seizure.