Surgical management and long-term outcome of pediatric patients with different subtypes of epilepsy associated with cerebral cavernous malformations

Cerebral cavernous malformations - An overview on genetics, clinical aspects and therapeutic strategies

Cerebral cavernous malformations (CCMs) are abnormally packed blood vessels lined with endothelial cells, that do not exhibit intervening tight junctions, lack muscular and elastic layers and are usually surrounded by hemosiderin and gliosis. CCMs may be sporadic or familial autosomal dominant (FCCMs) caused by loss of function mutations in CCM1 (KRIT1), CCM2 (MGC4607), and CCM3 (PDCD10) genes. In the FCCMs, patients have multiple CCMs, different family members are affected, and developmental venous anomalies are absent. CCMs may be asymptomatic or may manifest with focal neurological deficits with or without associated hemorrhage andseizures. Recent studies identify a digenic "triple-hit" mechanism involving the aquisition of three distinct genetic mutations that culminate in phosphatidylinositol-3-kinase (PIK3CA) gain of function, as the basis for rapidly growing and clinically symptomatic CCMs. The pathophysiology of CCMs involves signaling aberrations in the neurovascular unit, including proliferative dysangiogenesis, blood-brain barrier hyperpermeability, inflammation and immune mediated processes, anticoagulant vascular domain, and gut microbiome-driven mechanisms. Clinical trials are investigating potential therapies, magnetic resonance imaging and plasma biomarkers for hemorrhage and CCMs-related epilepsy, as well as different techniques of neuronavigation and neurosonology to guide surgery in order to minimize post-operatory morbidity and mortality. This review addresses the recent data about the natural history, genetics, neuroimaging and therapeutic approaches for CCMs.

Surgical management of pediatric intracranial cerebral cavernous malformations: a 10-year single-center experience

BACKGROUND

Cerebral cavernous malformations (CCMs) are low-flow vascular malformations made up of dilated vascular spaces without intervening parenchyma that can occur throughout the central nervous system. CCMs can occur sporadically or in familial forms. Presentation is diverse, ranging from incidental discovery of asymptomatic CCMs to drug-resistant epilepsy and hemorrhages.

METHODS

We describe the surgical management of CCMs in pediatric patients at Bambino Gesù Children's Hospital in Rome over the last 10 years. The cases have been stratified based on the clinical presentation and the relevant literature is discussed accordingly.

RESULTS

We discuss the rationale and technique used in these cases based on their presentation, as well as the generally positive outcomes we achieved with early surgical management, use of intraoperative ultrasound (ioUS) and intraoperative neuromonitoring.

CONCLUSIONS

Surgical management of pediatric CCMs is a safe and effective strategy, low rates of postoperative morbidity and partial resection were observed.

Surgical treatment of cavernous malformation-related epilepsy in children: case series, systematic review, and meta-analysis

OBJECTIVE

Cerebral cavernous malformations (CCMs) are cerebral vascular lesions that occasionally occur with seizures. We present a retrospective case series from IRCCS Gaslini Children's Hospital, a systematic review, and meta-analysis of the literature with the goal of elucidating the post-surgery seizure outcome in children with CCMs.

METHODS

a retrospective review of children with cavernous malformation related epilepsy who underwent surgery at Gaslini Children's Hospital from 2005 to 2022 was conducted. We also conducted a comprehensive search on PubMed/MEDLINE and Scopus databases from January 1989 to August 2022. Inclusion criteria were: presence of CCMs-related epilepsy, in under 18 years old subjects with a clear lesion site. Presence of post-surgery seizure outcome and follow-up ≥ 12 months.

RESULTS

we identified 30 manuscripts and 223 patients with CCMs-related epilepsy, including 17 patients reported in our series. We identified 85.7% Engel class I subjects. The risk of expected neurological deficits was 3.7%; that of unexpected neurological deficits 2.8%. We found no statistically significant correlations between Engel class and the following factors: site of lesion, type of seizure, drug resistance, duration of disease, type of surgery, presence of multiple CCMs. However, we found some interesting trends: longer disease duration and drug resistance seem to be more frequent in subjects in Engel class II, III and IV; multiple cavernomas would not seem to influence seizure outcome.

CONCLUSIONS

epilepsy surgery in children with CCMs is a safe and successful treatment option. Further studies are necessary to define the impact of clinical features on seizure prognosis.

Pediatric Neurostimulation and Practice Evolution

Since the late nineteenth century, the prevailing view of epilepsy surgery has been to identify a seizure focus in a medically refractory patient and eradicate it. Sadly, only a select number of the many who suffer from uncontrolled seizures benefit from this approach. With the development of safe, efficient stereotactic methods and targeted surgical therapies that can affect deep structures and modulate broad networks in diverse disorders, epilepsy surgery in children has undergone a paradigmatic evolutionary change. With modern diagnostic techniques such as stereo electroencephalography combined with closed loop neuromodulatory systems, pediatric epilepsy surgery can reach a much broader population of underserved patients.

Closing the Gap in Pediatric Hemorrhagic Stroke: A Systematic Review

Pediatric hemorrhagic stroke (HS) accounts for a large proportion of childhood strokes, 1 of the top 10 causes of pediatric deaths. Morbidity and mortality lead to significant socio-economic and psychosocial burdens. To understand published data on recognizing and managing children with HS, we conducted a systematic review of the literature presented here. We searched PubMed, Embase, CINAHL and the Cochrane Library databases limited to English language and included 174 studies, most conducted in the USA (52%). Terminology used interchangeably for HS included intraparenchymal/intracranial hemorrhage, spontaneous ICH, and cerebrovascular accident (CVA). Key assessments informing prognosis and management included clinical scoring (Glasgow coma scale), and neuroimaging. HS etiologies reported were systemic coagulopathy (genetic, acquired pathologic, or iatrogenic), or focal cerebrovascular lesions (brain arteriovenous malformations, cavernous malformations, aneurysms, or tumor vascularity). Several scales were used to measure outcome: Glasgow outcome score (GOS), Kings outcome score for head injury (KOSCHI), modified Rankin scale (mRS) and pediatric stroke outcome measure (PSOM). Most studies described treatments of at-risk lesions. Few studies described neurocritical care management including raised ICP, seizures, vasospasm, or blood pressure. Predictors of poor outcome included ethnicity, comorbidity, location of bleed, and hematoma >2% of total brain volume. Motor and cognitive outcomes followed independent patterns. Few studies reported on cognitive outcomes, rehabilitation, and transition of care models. Interdisciplinary approach to managing HS is urgently needed, informed by larger cohort studies targeting key clinical question (eg development of a field-guide for the clinician managing patients with HS that is reproducible internationally).

Earlier Age at Surgery for Brain Cavernous Angioma-Related Epilepsy May Achieve Complete Seizure Freedom without Aid of Anti-Seizure Medication

Background: The present study hypothesized that some factors may distinguish between patients with a brain cavernous angioma (BCA), who were free from anti-seizure medication (ASM), and patients who still required ASMs postoperatively. The purpose of the study was thus to identify factors associated with ceasing ASMs for patients with drug-resistant epilepsy secondary to BCA, who underwent BCA removal surgery. Methods: We divided patients into those with drug-resistant epilepsy secondary to BCA who achieved complete seizure freedom without ASMs a year after surgery (No-ASM group) (International League Against Epilepsy (ILAE) classification class I with no epileptiform discharges), and others (ASM group) (ILAE classification ≤ II and/or epileptiform discharges). We statistically compared groups in terms of: (1) age at operation; (2) history of epilepsy; (3) size of BCA; and (4) location of BCA. Results: Overall, a year after the surgery, the No-ASM group comprised 12 patients (48%), and the ASM group comprised 13 patients (52%). In both multi- and univariate logistic regression analyses, age at BCA removal surgery correlated significantly with the No-ASM group (p = 0.043, p = 0.019), but history of epilepsy did not (p = 0.581, p = 0.585). Conclusions: Earlier age at surgery for patients with drug-resistant epilepsy is encouraged to achieve complete seizure freedom without the need for ASMs when the cause of epilepsy is BCA.

A systematic review and meta-analysis of surgeries performed for cerebral cavernous malformation-related epilepsy in pediatric patients

BACKGROUND

The clinical benefit of surgery for the treatment of cerebral cavernous malformation (CCM)-related epilepsy in pediatric patients is still controversial. Although surgical treatment of CCM-related epilepsy in children is widely recognized, the clinical benefits of controlling the seizure rate must be balanced against the risk of leading to perioperative morbidity.

METHODS

We conducted a comprehensive search to identify relevant studies via Ovid Medline, Web of Science and PubMed (January 1995-June 2020). The following search terms were used: "hemangioma, cavernous, central nervous system," "brain cavernous hemangioma," "cerebral cavernous hemangioma," "CCM," "epilepsy," and "seizures." The seizure control rate and the risk of postoperative adverse outcomes along with their 95% confidence intervals (CIs) were calculated.

RESULTS

A total of 216 patients across 10 studies were included in meta-analysis. The results showed that the control rate of epilepsy was 88% (95% CI: 76-95%). Four percent (95% CI: 2-10%) of the patients experienced temporary symptomatic adverse effects following surgical resection, and 3% (95% CI: 0-26%) of the patients developed permanent symptomatic adverse effects in the long-term follow-up after surgical excision of the CCMs. None of the patients died as a result of the CCMs or surgical treatment.

CONCLUSION

Surgery is an effective and safe treatment for CCM -related epilepsy in pediatric patients with a low risk of postoperative complications and death.

Intra-operative electrocorticography results and postoperative pathological findings are associated with epileptic outcomes in patients with cerebral cavernous malformations presenting with epilepsy

OBJECTIVES

The purpose of this study was to determine whether intraoperative electrocorticography (ECoG) results and postoperative pathological findings are associated with long-term epileptic outcomes in patients with cerebral cavernous malformations (CCMs).

METHODS AND MATERIALS

To identify all consecutive patients with surgically treated CCM-related epilepsy (CRE) referred to our hospital, our prospectively maintained database of patients with CCM was reviewed (NCT03467295). For these patients, an ECoG-guided extended lesionectomy was performed, in which the CCM, surrounding hemosiderin, and detected epileptic foci were removed. Intraoperative ECoG results and postoperative pathological findings were documented in detail. Engel Class I was defined as a favorable outcome, while Engel Class II-IV was considered an unfavorable outcome. The patients were followed up for at least 2 years. The relationship between ECoG results, postoperative pathological findings, and epileptic outcomes was analyzed.

RESULTS

A total of 522 patients with CCM were reviewed, and 85 patients with epileptic CCM were enrolled in this study. At the last clinical visit, 83.5 % of the patients experienced favorable postoperative outcomes. Multivariate analysis revealed that residual epileptic waves detected by intraoperative ECoG (OR 13.64; Cl 2.13-87.11; p = 0.006) and concomitant focal cortical dysplasia (FCD) (OR 11.37; Cl 1.63-79.27; p = 0.014) were independent factors significantly correlated with long-term epileptic outcomes. Most (61; 93.8 %) of the 65 patients with CRE without FCD achieved favorable outcomes.

CONCLUSION

Residual epileptiform discharges after excision and concomitant FCD may be associated with poorer long-term epileptic outcomes in patients with CRE. Close follow-up and strict administration of oral antiepileptic drugs may be needed for these patients.

Spontaneous Intracranial Hemorrhage: A Sign of Cavernous Angioma Diagnosis in Pediatric Age Group

Cerebral cavernous malformation (CCM) is a developmental abnormality of blood vessels that supply the brain. It is composed of large, adjacent capillaries which contain little or no neural tissue. They mostly occur in the supratentorial region. However, the occurrence of these vascular lesions can be seen at different sites of the central nervous system (CNS). The prevalence of CCM is estimated to be 0.4% in the general population and among the affected patients, 18.7% have multiple lesions. However, about 30-50% of CCM cases are asymptomatic and are found incidentally. Here we report a case of an eight-year-old girl with a massive hemorrhagic presentation of a left parietooccipital CCM.

Prosopagnosia seizure semiology in a 10-year-old boy: a functional neuroimaging study

We illustrate a case of post-traumatic recurrent transient prosopagnosia in a paediatric patient with a right posterior inferior temporal gyrus haemorrhage seen on imaging and interictal electroencephalogram abnormalities in the right posterior quadrant. Face recognition area mapping with magnetoencephalography (MEG) and functional MRI (fMRI) was performed to clarify the relationship between the lesion and his prosopagnosia, which showed activation of the right fusiform gyrus that colocalised with the lesion. Lesions adjacent to the right fusiform gyrus can result in seizures presenting as transient prosopagnosia. MEG and fMRI can help to attribute this unique semiology to the lesion.

Cerebral cavernous malformation remnants after surgery: a single-center series with long-term bleeding risk analysis

The aim of this work is to investigate the long-term bleeding risk of cerebral cavernous malformation (CCM) remnants. A review of clinical, radiological, operative, and post-operative data of a cerebral cavernous malformation (CCMs) prospective database was performed. Fisher’s exact test and Mann-Whitney U-test were used to assess differences between non-hemorrhagic and hemorrhagic CCM remnants for 14 variables. Recursive partitioning analysis was performed to assess the order of variables most associated with CCM remnant bleeding. Twenty-four patients out of 126 had a CCM post-surgical remnant. Of these, 7 had at least one post-operative hemorrhagic event. The mean follow-up was 80.7 months (range 12–144). CCM post-surgical remnant bleeding presented mostly with acute headache (50%) and focal neurological deficit (25%); in the remaining cases, the hemorrhage was asymptomatic. Retreatment was performed in two patients, with surgery and radiosurgery, respectively; no treatment was performed in the majority of cases. All patients ranked as non-II, according to Zabramski classification, did not show any post-surgical bleeding. The presence of a pre-operative perilesional hemosiderin ring was highly significant in predicting post-surgical bleeding (sensitivity = 0.94, specificity = 0.88) and incorrectly predicted bleeding in only two of the 24 patients. This study provides an evaluation of clinical and radiological factors influencing the bleeding risk of a CCM post-surgical remnant in a homogeneous population. Perilesional hemosiderin ring and Zabramski Type II appear to strongly condition the bleeding risk of a CCM post-surgical remnant.

Emerging Pharmacologic Targets in Cerebral Cavernous Malformation and Potential Strategies to Alter the Natural History of a Difficult Disease: A Review

Importance

Cerebral cavernous malformations (CCMs) are vascular lesions of the brain that may lead to hemorrhage, seizures, and neurologic deficits. Most are linked to loss-of-function mutations in 1 of 3 genes, namely CCM1 (originally called KRIT1), CCM2 (MGC4607), or CCM3 (PDCD10), that can either occur as sporadic events or are inherited in an autosomal dominant pattern with incomplete penetrance. Familial forms originate from germline mutations, often have multiple intracranial lesions that grow in size and number over time, and cause an earlier and more severe presentation. Despite active preclinical research on a few pharmacologic agents, clinical translation has been slow. Open surgery and, in some cases, stereotactic radiosurgery remain the only effective treatments, but these options are limited by lesion accessibility and are associated with nonnegligible rates of morbidity and mortality.

Observations

We discuss the limits of CCM management and introduce findings from in vitro and in vivo studies that provide insight into CCM pathogenesis and indicate molecular mechanisms as potential therapeutic targets. These studies report dysregulated cellular pathways shared between CCM, cardiovascular diseases, and cancer. They also suggest the potential effectiveness of proper drug repurposing in association with, or as an alternative to, targeted interventions.

Conclusions and Relevance

We propose methods to exploit specific molecular pathways to design patient-tailored therapeutic approaches in CCM, with the aim to alter its natural progression. In this scenario, the lack of effective pharmacologic options remains a critical barrier that poses an unfulfilled and urgent medical need.

Cavernous angiomas: deconstructing a neurosurgical disease

Cavernous angioma (CA) is also known as cavernoma, cavernous hemangioma, and cerebral cavernous malformation (CCM) (National Library of Medicine Medical Subject heading unique ID D006392). In its sporadic form, CA occurs as a solitary hemorrhagic vascular lesion or as clustered lesions associated with a developmental venous anomaly. In its autosomal dominant familial form (Online Mendelian Inheritance in Man #116860), CA is caused by a heterozygous germline loss-of-function mutation in one of three genes-CCM1/KRIT1, CCM2/Malcavernin, and CCM3/PDCD10-causing multifocal lesions throughout the brain and spinal cord.In this paper, the authors review the cardinal features of CA's disease pathology and clinical radiological features. They summarize key aspects of CA's natural history and broad elements of evidence-based management guidelines, including surgery. The authors also discuss evidence of similar genetic defects in sporadic and familial lesions, consequences of CCM gene loss in different tissues at various stages of development, and implications regarding the pathobiology of CAs.The concept of CA with symptomatic hemorrhage (CASH) is presented as well as its relevance to clinical care and research in the field. Pathobiological mechanisms related to CA include inflammation and immune-mediated processes, angiogenesis and vascular permeability, microbiome driven factors, and lesional anticoagulant domains. These mechanisms have motivated the development of imaging and plasma biomarkers of relevant disease behavior and promising therapeutic targets.The spectrum of discoveries about CA and their implications endorse CA as a paradigm for deconstructing a neurosurgical disease.

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.

Usefulness of Ultrasound-Guided Microsurgery in Cavernous Angioma Removal

BACKGROUND

Primary elements of surgical treatment of cavernous angiomas (CAs) are precise lesion identification and optimal trajectory determination. Navigation techniques allow for better results compared to microsurgery alone. In this study, we examined the benefits of intraoperative ultrasound (IOUS) use as an adjunct to standard localization systems.

METHODS

We retrospectively analyzed 59 CAs, comparing outcomes in 2 groups of patients: 34 who underwent frame-based or frameless navigation-assisted microsurgery (no-IOUS group) and 25 who underwent IOUS-guided microsurgery associated with these techniques (IOUS group).

RESULTS

The use of IOUS did not significantly increase the surgery time (mean, 172 ± 1.7 minutes in the IOUS group and 192.6 ± 11.5 in no-IOUS group; P = 0.08). In all 25 patients in the IOUS group, IOUS allowed for ready identification of CA as a hyperechoic mass. At the last follow-up (mean, 41.7 ± 3.5 months postsurgery), 95.2% of the IOUS group and 80.8% of the no-IOUS group had a modified Rankin Scale score of 0-1 and an Extended Glasgow Outcome Scale score of 7-8 (P = 0.2), with 100% and 64%, respectively, included in Engel outcome scale class IA (P = 0.006). Complete removal, as confirmed on postoperative magnetic resonance imaging, was achieved in all patients in the IOUS group and in almost all (97.1%; P = 0.4) patients in the no-IOUS group.

CONCLUSIONS

IOUS is a valid tool for the intraoperative identification of CAs. Implementation of standard localization methods with IOUS guidance was associated with complete resection in all cases, without increasing surgical time. Compared with microsurgery without IOUS guidance, long-term functional outcomes showed better trends, and the epilepsy-free rate was significantly higher.

High-frequency oscillations detected in ECoG recordings correlate with cavernous malformation and seizure-free outcome in a child with focal epilepsy: A case report

Epilepsy associated with cavernous malformation (CM) often requires surgical resection of seizure focus to achieve seizure‐free outcome. High‐frequency oscillations (HFOs) in intracranial electroencephalogram (EEG) are reported as potential biomarkers of epileptogenic regions, but to our knowledge there are no data on the existence of HFOs in CM‐caused epilepsy. Here we report our experience of the identification of the seizure focus in a 3‐year‐old pediatric patient with intractable epilepsy associated with CM. The electrocorticographic recordings were obtained from a 64‐contact grid over 2 days in the epilepsy monitoring unit (EMU). The spatial distribution of HFOs and epileptic spikes were estimated from recording segments right after the electrode placement, during sleep and awake states separately. The HFO distribution showed consistency with the perilesional region; the location of spikes varied over days and did not correlate with the lesion. The HFO spatial distribution was more compact in sleep state and pinpointed the contacts sitting on the CM border. Following the resection of the CM and the hemosiderin ring, the patient became seizure‐free. This is the first report describing HFOs in a pediatric patient with intractable epilepsy associated with CM and shows their potential in identifying the seizure focus.

Awad I, Dahlem K, Flemming K, Hart B, Kim H, Jusue-Torres I, Kondziolka D, Lee C, Morrison L, Rigamonti D, Rebeiz T, Tournier-Lasserve E, Waggoner D, Whitehead K. Synopsis of Guidelines for the Clinical Management of Cerebral Cavernous Malformations: Consensus Recommendations Based on Systematic Literature Review by the Angioma Alliance Scientific Advisory Board Clinical Experts Panel

BACKGROUND

Despite many publications about cerebral cavernous malformations (CCMs), controversy remains regarding diagnostic and management strategies.

OBJECTIVE

To develop guidelines for CCM management.

METHODS

The Angioma Alliance ( www.angioma.org ), the patient support group in the United States advocating on behalf of patients and research in CCM, convened a multidisciplinary writing group comprising expert CCM clinicians to help summarize the existing literature related to the clinical care of CCM, focusing on 5 topics: (1) epidemiology and natural history, (2) genetic testing and counseling, (3) diagnostic criteria and radiology standards, (4) neurosurgical considerations, and (5) neurological considerations. The group reviewed literature, rated evidence, developed recommendations, and established consensus, controversies, and knowledge gaps according to a prespecified protocol.

RESULTS

Of 1270 publications published between January 1, 1983 and September 31, 2014, we selected 98 based on methodological criteria, and identified 38 additional recent or relevant publications. Topic authors used these publications to summarize current knowledge and arrive at 23 consensus management recommendations, which we rated by class (size of effect) and level (estimate of certainty) according to the American Heart Association/American Stroke Association criteria. No recommendation was level A (because of the absence of randomized controlled trials), 11 (48%) were level B, and 12 (52%) were level C. Recommendations were class I in 8 (35%), class II in 10 (43%), and class III in 5 (22%).

CONCLUSION

Current evidence supports recommendations for the management of CCM, but their generally low levels and classes mandate further research to better inform clinical practice and update these recommendations. The complete recommendations document, including the criteria for selecting reference citations, a more detailed justification of the respective recommendations, and a summary of controversies and knowledge gaps, was similarly peer reviewed and is available on line www.angioma.org/CCMGuidelines .

Surgical Management of Pediatric Epilepsy: Decision-Making and Outcomes

First-line treatment for epilepsy is antiepileptic drug and requires an interdisciplinary approach and enduring commitment and adherence from the patient and family for successful outcome. Despite adherence to antiepileptic drugs, refractory epilepsy occurs in approximately 30% of children with epilepsy, and surgical treatment is an important intervention to consider. Surgical management of pediatric epilepsy is highly effective in selected patients with refractory epilepsy; however, an evidence-based protocol, including best methods of presurgical imaging assessments, and neurodevelopmental and/or behavioral health assessments, is not currently available for clinicians. Surgical treatment of epilepsy can be critical to avoid negative outcomes in functional, cognitive, and behavioral health status. Furthermore, it is often the only method to achieve seizure freedom in refractory epilepsy. Although a large literature base can be found for adults with refractory epilepsy undergoing surgical treatment, less is known about how surgical management affects outcomes in children with epilepsy. The purpose of the review was fourfold: (1) to evaluate the available literature regarding presurgical assessment and postsurgical outcomes in children with medically refractory epilepsy, (2) to identify gaps in our knowledge of surgical treatment and its outcomes in children with epilepsy, (3) to pose questions for further research, and (4) to advocate for a more unified presurgical evaluation protocol including earlier referral for surgical candidacy of pediatric patients with refractory epilepsy. Despite its effectiveness, epilepsy surgery remains an underutilized but evidence-based approach that could lead to positive short- and long-term outcomes for children with refractory epilepsy.

Surgical strategies for pediatric epilepsy

Pediatric epilepsy is a debilitating condition that impacts millions of patients throughout the world. Approximately 20-30% of children with recurrent seizures have drug-resistant epilepsy (DRE). For these patients, surgery offers the possibility of not just seizure freedom but significantly improved neurocognitive and behavioral outcomes. The spectrum of surgical options is vast, ranging from outpatient procedures such as vagus nerve stimulation to radical interventions including hemispherectomy. The thread connecting all of these interventions is a common goal-seizure freedom, an outcome that can be achieved safely and durably in a large proportion of patients. In this review, we discuss many of the most commonly performed surgical interventions and describe the indications, complications, and outcomes specific to each.

Seizure outcomes in children with epilepsy after resective brain surgery

PURPOSE

To assess the role of resective brain surgery in childhood epilepsy.

METHODOLOGY

We retrospectively analysed the seizure outcomes in 55 children with epilepsy who had resective brain surgery between 1997 and 2012, at our centre. The children were 1.5-18 years at the time of surgery; their seizure onset was between 0.2 andto 15 years of age. 48 had refractory epilepsy. One child died of tumour progression. Follow-up duration in the survivors ranged from 2 to -16 years (mean: 9).Presurgical evaluation included clinical profiles, non-invasive V-EEG monitoring, neuroimaging with MRIs in all; SPECT and PET in selected patients. 54 had intraoperative ECoG.

RESULTS

An Engel Class 1 outcome was seen in 78% of the cohort, with 67% being off all AEDs at the most recent follow-up. Children with tumours constituted the majority (56%), with 87% of this group showing a Class 1 outcome and 84% being off AEDs. Children with cortical dysplasia had a Class 1 outcome in 56%.

CONCLUSION

Resective brain surgery is an efficacious option in some children with epilepsy. We found ECoG useful to tailor the cortical resection and in our opinion ECoG contributed to the good seizure outcomes.

Paraventricular or centrum ovale cavernous hemangioma involving the pyramidal tract in children: intraoperative MRI and functional neuronavigation-guided resection

OBJECTIVES

In this study, we investigated whether visualization of the pyramidal tract and intraoperative MRI combined with functional navigation was helpful in the resection of paraventricular or centrum ovale cavernous hemangioma in children.

METHODS

Twelve patients with cavernous hemangioma located in the paraventricular area or in the centrum ovale adjacent to the pyramidal tract were prospectively enrolled in the study. The pyramidal tract of all patients was visualized preoperatively, and all patients underwent tailored craniotomy with white matter trajectory to resect the lesion, with the help of intraoperative MRI and microscope-based functional neuronavigation.

RESULTS

In our study, of the total of 12 patients (nine males and three females), five patients had lesions on the left side, and seven had lesions located in the right hemisphere. The lesion volume varied from 0.2 to 11.45 cm(3). In seven cases, the distance of the lesion from the pyramidal tract was 0-5 mm (the 0-5 mm group), and five cases were in the 5-10 mm group. The 3D visualization of the lesion and the pyramidal tract helped the surgeon design the optimal surgical approach and trajectory. Intraoperative functional neuronavigation allowed them to obtain access to the lesion accurately and precisely. All lesions had been removed totally at the end of the surgery. Compared with the preoperative level, muscle strength at 2 weeks had decreased in six cases, was unchanged in four cases, and improved in two cases; at 3 months, it was improved in five cases, unchanged in six cases, and decreased in one case.

CONCLUSIONS

Pyramidal tract visualization and intraoperative MRI combined with functional neuronavigation can aid in safe removal of paraventricular or centrum ovale cavernous hemangioma involving the pyramidal tract.