Cavernoma-related epilepsy: Review and recommendations for management-Report of the Surgical Task Force of the ILAE Commission on Therapeutic Strategies

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.

Medical management and surgery versus medical management alone for symptomatic cerebral cavernous malformation (CARE): a feasibility study and randomised, open, pragmatic, pilot phase trial

BACKGROUND

The highest priority uncertainty for people with symptomatic cerebral cavernous malformation is whether to have medical management and surgery or medical management alone. We conducted a pilot phase randomised controlled trial to assess the feasibility of addressing this uncertainty in a definitive trial.

METHODS

The CARE pilot trial was a prospective, randomised, open-label, assessor-blinded, parallel-group trial at neuroscience centres in the UK and Ireland. We aimed to recruit 60 people of any age, sex, and ethnicity who had mental capacity, were resident in the UK or Ireland, and had a symptomatic cerebral cavernous malformation. Computerised, web-based randomisation assigned participants (1:1) to medical management and surgery (neurosurgical resection or stereotactic radiosurgery) or medical management alone, stratified by the neurosurgeon's and participant's consensus about the intended type of surgery before randomisation. Assignment was open to investigators, participants, and carers, but not clinical outcome event adjudicators. Feasibility outcomes included site engagement, recruitment, choice of surgical management, retention, adherence, data quality, clinical outcome event rate, and protocol implementation. The primary clinical outcome was symptomatic intracranial haemorrhage or new persistent or progressive non-haemorrhagic focal neurological deficit due to cerebral cavernous malformation or surgery during at least 6 months of follow-up. We analysed data from all randomly assigned participants according to assigned management. This trial is registered with ISRCTN (ISRCTN41647111) and has been completed.

FINDINGS

Between Sept 27, 2021, and April 28, 2023, 28 (70%) of 40 sites took part, at which investigators screened 511 patients, of whom 322 (63%) were eligible, 202 were approached for recruitment, and 96 had collective uncertainty with their neurosurgeon about whether to have surgery for a symptomatic cerebral cavernous malformation. 72 (22%) of 322 eligible patients were randomly assigned (mean recruitment rate 0·2 [SD 0·25] participants per site per month) at a median of 287 (IQR 67-591) days since the most recent symptomatic presentation. Participants' median age was 50·6 (IQR 38·6-59·2) years, 68 (94%) of 72 participants were adults, 41 (57%) were female, 66 (92%) were White, 56 (78%) had a previous intracranial haemorrhage, and 28 (39%) had a previous epileptic seizure. The intended type of surgery before randomisation was neurosurgical resection for 19 (26%) of 72, stereotactic radiosurgery for 44 (61%), and no preference for nine (13%). Baseline clinical and imaging data were complete for all participants. 36 participants were randomly assigned to medical management and surgery (12 to neurosurgical resection and 24 to stereotactic radiosurgery) and 36 to medical management alone. Three (4%) of 72 participants withdrew, one was lost to follow-up, and one declined face-to-face follow-up, leaving 67 (93%) retained at 6-months' clinical follow-up. 61 (91%) of 67 participants with follow-up adhered to the assigned management strategy. The primary clinical outcome occurred in two (6%) of 33 participants randomly assigned to medical management and surgery (8·0%, 95% CI 2·0-32·1 per year) and in two (6%) of 34 participants randomly assigned to medical management alone (7·5%, 1·9-30·1 per year). Investigators reported no deaths, no serious adverse events, one protocol violation, and 61 protocol deviations.

INTERPRETATION

This pilot phase trial exceeded its recruitment target, but a definitive trial will require extensive international engagement.

FUNDING

National Institute for Health and Care Research.

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.

Role of Rho-Associated Kinase in the Pathophysiology of Cerebral Cavernous Malformations

Cerebral cavernous malformations (CCMs) are vascular lesions characterized by a porous endothelium. The lack of a sufficient endothelial barrier can result in microbleeds and frank intracerebral hemorrhage. A primary mechanism for lesion development is a sequence variant in at least 1 of the 3 CCM genes (CCM1, CCM2, and CCM3), which influence various signaling pathways that lead to the CCM phenotype. A common downstream process associated with CCM gene loss of function involves overactivation of RhoA and its effector Rho-associated kinase (ROCK). In this study, we review RhoA/ROCK-related mechanisms involved in CCM pathophysiology as potential therapeutic targets. Literature searches were conducted in PubMed using combinations of search terms related to RhoA/ROCK and CCMs. In endothelial cells, CCM1, CCM2, and CCM3 proteins normally associate to form the CCM protein complex, which regulates the functions of a wide variety of protein targets (e.g., MAP3K3, SMURF1, SOK-1, and ICAP-1) that directly or indirectly increase RhoA/ROCK activity. Loss of CCM complex function and increased RhoA/ROCK activity can lead to the formation of stress fibers that contribute to endothelial junction instability. Other RhoA/ROCK-mediated pathophysiologic outcomes include a shift to a senescence-associated secretory phenotype (primarily mediated by ROCK2), which is characterized by endothelial cell migration, cell cycle arrest, extracellular matrix degradation, leukocyte chemotaxis, and inflammation. ROCK represents a potential therapeutic target, and direct (fasudil, NRL-1049) and indirect (statins) ROCK inhibitors have demonstrated various levels of efficacy in reducing lesion burden in preclinical models of CCM. Current (atorvastatin) and planned (NRL-1049) clinical studies will determine the efficacy of ROCK inhibitors for CCM in humans, for which no US Food and Drug Administration-approved or EU-approved pharmacologic treatment exists.

A small frontal lobe cavernoma presenting with headache mimicking migraine and complex focal seizure: A case report

Cavernoma, or cerebral cavernous angioma, are hamartomatous lesions formed by sinusoidal vascular spaces without cerebral parenchyma in between. Cavernoma is a rare disorder that is diagnosed infrequently and incidentally, so it is called incidentaloma. However, cavernoma can present with seizures, headaches, and other focal neurological deficits, with seizures being the most frequent presentation. Cavernoma is angiographically concealed, and it's diagnosis is challenging. So, the cavernoma is diagnosed based on an MRI. We present the rare case of a patient who presented with a complex focal seizure and migraine-like headache caused by a small frontal lobe cavernoma.

Kindling in humans: Does secondary epileptogenesis occur?

The relevance of secondary epileptogenesis for human epilepsy remains a controversial subject decades after it was first described in animal models. Whether or not a previously normal brain region can become independently epileptogenic through a kindling-like process has not, and cannot, be definitely proven in humans. Rather than reliance on direct experimental evidence, attempts to answering this question must depend on observational data. In this review, observations based largely upon contemporary surgical series will advance the case for secondary epileptogenesis in humans. As will be argued, hypothalamic hamartoma-related epilepsy provides the strongest case for this process; all the stages of secondary epileptogenesis can be observed. Hippocampal sclerosis (HS) is another pathology where the question of secondary epileptogenesis frequently arises, and observations from bitemporal and dual pathology series are explored. The verdict here is far more difficult to reach, in large part because of the scarcity of longitudinal cohorts; moreover, recent experimental data have challenged the claim that HS is acquired consequent to recurrent seizures. Synaptic plasticity more than seizure-induced neuronal injury is the likely mechanism of secondary epileptogenesis. Postoperative running-down phenomenon provides the best evidence that a kindling-like process occurs in some patients, evidenced by its reversal. Finally, a network perspective of secondary epileptogenesis is considered, as well as the possible role for subcortical surgical interventions.

MR-Guided Focused Ultrasound for Refractory Epilepsy: Where Are We Now?

Epilepsy is one of the most common neurological diseases in both adults and children. Despite improvements in medical care, 20 to 30% of patients are still resistant to the best medical treatment. The quality of life, neurologic morbidity, and even mortality of patients are significantly impacted by medically intractable epilepsy. Nowadays, conservative therapeutic approaches consist of increasing medication dosage, changing to a different anti-seizure drug as monotherapy, and combining different antiseizure drugs using an add-on strategy. However, such measures may not be sufficient to efficiently control seizure recurrence. Resective surgery, ablative procedures and non-resective neuromodulatory (deep-brain stimulation, vagus nerve stimulation) treatments are the available treatments for these kinds of patients. However, invasive procedures may involve lengthy inpatient stays for the patients, risks of long-term neurological impairment, general anesthesia, and other possible surgery-related complications (i.e., hemorrhage or infection). In the last few years, MR-guided focused ultrasound (MRgFUS) has been proposed as an emerging treatment for neurological diseases because of technological advancements and the goal of minimally invasive neurosurgery. By outlining the current knowledge obtained from both preclinical and clinical studies and discussing the technical opportunities of this therapy for particular epileptic phenotypes, in this perspective review, we explore the various mechanisms and potential applications (thermoablation, blood-brain barrier opening for drug delivery, neuromodulation) of high- and low-intensity ultrasound, highlighting possible novel strategies to treat drug-resistant epileptic patients who are not eligible or do not accept currently established surgical approaches. Taken together, the available studies support a possible role for lesional treatment over the anterior thalamus with high-intensity ultrasound and neuromodulation of the hippocampus via low-intensity ultrasound in refractory epilepsy. However, more studies, likely conceiving epilepsy as a network disorder and bridging together different scales and modalities, are required to make ultrasound delivery strategies meaningful, effective, and safe.

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.

Seizure outcome in medically treated patients with adult-onset epilepsy and cerebral cavernous malformation

PURPOSE

We evaluated long-term seizure outcomes of antiseizure medications (ASMs) and risk factors for drug resistance in patients with adult-onset epilepsy associated with cerebral cavernous malformation (CCM).

MATERIALS AND METHODS

This retrospective observational study included patients newly diagnosed with adult-onset focal epilepsy associated with CCM. Patients received individualized treatments with ASMs. All patients were followed-up for at least 2 years. The main outcome measure was terminal 2 year seizure freedom (2-YSF).

RESULTS

Forty eight subjects (28 men and 20 women) were included. Thirty-one (64.6%) subjects achieved a terminal 2-YSF (range 2.0-17.0 years). After treatment with the first drug regimen, 31 (64.6%) subjects achieved 2-YSF, with 23 remaining seizure-free until final follow-up visit. Of the 23 subjects treated with the second drug regimen and the six treated with the third drug regimen, ten (43.5%) and one (16.7%), respectively, achieved a terminal 2-YSF. Stepwise logistic regression analyses showed that terminal 2-YSF was negatively associated with epileptiform discharge on EEG at the time of diagnosis (odds ratio = 0.214, p = 0.047) and tended to be associated with age ≥ 45 years at seizure onset (odds ratio = 4.260, p = 0.056).

CONCLUSION

The present study found that 64.6% of CCM patients with adult-onset epilepsy achieved terminal 2-YSF after ASM initiation. Interictal epileptiform discharge on EEG at the time of diagnosis was associated with poor prognosis. Failure to achieve sustained seizure freedom after two ASMs may indicate the need for surgical treatment.

Epilepsy associated with cerebral cavernous malformations managed with stereotactic radiosurgery: an international, multicenter study

OBJECTIVE

Stereotactic radiosurgery (SRS) has been proposed as an alternative to resection for epilepsy control in patients with cerebral cavernous malformations (CCM) located in critical areas.

METHODS

This multicentric, retrospective study evaluated seizure control in patients with a solitary CCM and a history of at least one seizure prior to SRS.

RESULTS

109 patients (median age at diagnosis 28.9 years, interquartile range (IQR) 16.4 years] were included. Prior to SRS, 2 (1.8%) were seizure-free without medication, 35 (32.1%) were seizure-free with antiseizure medications (ASM), 17 (15.6%) experienced an improvement of at least 50% in seizure frequency/intensity with ASM, and 55 (50.5%) experienced an improvement of less than 50% in seizure frequency/intensity with ASM. At a median follow-up of 3.5 years post-SRS (IQR: 4.9), 52 (47.7%) patients were Engel class I, 13 (11.9%) class II, 17 (15.6%) class III, 22 (20.2%) class IVA or IVB and 5 (4.6%) class IVC. For the 72 patients who had seizures despite medication prior to SRS, a delay > 1.5 years between epilepsy presentation and SRS decreased the probability to become seizure-free, HR 0.25 (95% CI 0.09-0.66), p = 0.006. The probability of achieving Engel I at the last follow-up was 23.6 (95% CI 12.7-33.1) and 31.3% (95% CI 19.3-50.8) at 2 and 5 years respectively. 27 patients were considered as having drug-resistant epilepsy. At a median follow-up of 3.1 years (IQR: 4.7), 6 (22.2%) of them were Engel I, 3 (11.1%) Engel II, 7 (25.9%) Engel III, 8 (29.6%) Engel IVA or IVB and 3 (11.1%) Engel IVC.

INTERPRETATION

47.7% of patients managed with SRS for solitary CCM presenting with seizures achieved Engel class I at the last follow-up.

Outcome after conservative or surgical treatment for new-onset epilepsy in children with cerebral cavernous malformation

OBJECTIVE

This study aimed to investigate and compare the outcome of conservatively or surgically treated children with cerebral cavernous malformation (CCM) and new-onset CCM-related epilepsy (CRE) during a 5-year period.

METHODS

In this observational monocentric cohort study, data were collected ambispectivley. Our database was screened for CCM patients treated between 2003 and 2020. Patients ≤18 years of age with complete magnetic resonance imaging dataset, clinical baseline characteristics, and diagnosis of new-onset CRE were included. Definite seizure control was classified as International League Against Epilepsy class <2. Functional outcome was assessed using the modified Rankin Scale score. CRE patients were separated into two groups according to their treatment modality. Seizure control, intake of antiseizure medication, and functional outcomes were assessed. Systematic literature research was performed to identify other cases of new-onset CRE in children and to compare the collected data with published data.

RESULTS

Thirty-nine pediatric CRE patients were analyzed. A total of 18 (46.1%) patients were conservatively treated, while 21 (53.8%) underwent surgical CCM removal. While the functional outcome was similar in both groups at the last follow-up, definite seizure control was better in the surgical group (77.8%) than in the conservative group (25.0%) both after 5-years of follow-up (p = 0.038), and at last follow-up with 85.7% versus 50% respectively (p = 0.035). We found substantially higher rates of discontinuation of antiseizure medication at the last available follow-up in patients undergoing surgical resection (p = 0.009). The systematic literature review identified 4 studies with a total of 30 additional children with early onset CRE.

CONCLUSION

Surgical treatment of pediatric patients with new-onset CRE had higher rates of complete seizure control and early discontinuation of antiseizure medication than conservative treatment. Neurological outcomes of patients managed surgically or conservatively were comparable. These results encourage early surgical management of children with CRE even in the absence of pharmacoresistant epilepsy, but randomized control trials are urgently needed for further decision-making.

Is the Patient State Index a reliable parameter as guide to anaesthesiology in cranial neurosurgery? A first intraoperative study and a literature review

BACKGROUND

Patient State Index (PSI) and Suppression Ratio (SR) are two indices calculated by quantitative analysis of EEG used to estimate the depth of anaesthesia but their validation in neurosurgery must be done. Our aim was to investigate the congruity PSI and SR with raw EEG monitoring in neurosurgery.

METHODS

We included 34 patients undergoing elective cranial neurosurgery. Each patient was monitored by a SedLine device (PSI and SR) and by raw EEG. To appraise the agreement between PSI, SR and EEG Suppr%, Bland-Altman analysis was used. We also correlated the PSI and SR recorded at different times during surgery to the degree of suppression of the raw EEG data by Spearman's rank correlation coefficient. For a comparison with previous data we made an international literature review according to PRISMA protocol.

RESULTS

At all recording times, we found that there is a strong agreement between PSI and raw EEG. We also found a significant correlation for both PSI and SR with the EEG suppression percentage (p < 0.05), but with a broad dispersion of the individual values within the confidence interval.

CONCLUSION

The Masimo SedLine processed EEG monitoring system can be used as a guide in the anaesthetic management of patients during elective cranial neurosurgery, but the anaesthesiologist must be aware that previous correlations between PSI and SR with the suppression percentage may not always be valid in all individual patients. The use of an extended visual raw EEG evaluated by an expert electroencephalographer might help to provide better guidance.

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.

Incidence of Cerebral Cavernous Malformation-Related Epilepsy in Children: A Single Center Survey

INTRODUCTION

Cerebral cavernous malformations (CCMs) are rare developmental cerebrovascular malformations. The risk of epilepsy is high in patients with CCMs, but the incidence of epilepsy has not been reported in a pure pediatric population. We herein present 14 pediatric cases of CCMs, including five with CCM-related epilepsy, and examine the incidence of CCM-related epilepsy in this pediatric population.  Methods: Pediatric patients with CCMs who visited our Hospital between November 1, 2001, to September 31, 2020, were retrospectively screened for inclusion, and 14 were enrolled.  Results: Fourteen enrolled patients were divided into two groups based on the presence or absence of CCM-related epilepsy. The "CCM-related epilepsy group" (n = 5) consisted of five males with a median age of 4.2 (range: 0.3-8.5) years at the first visit. The "non-epilepsy group" (n = 9) consisted of seven males and two females with a median age of 3.5 (range: 1.3-11.5) years at the first visit. The prevalence of CCM-related epilepsy at the time of the present analysis was 35.7%. Follow-up periods in CCM-related epilepsy and non-epilepsy groups were 19.3 and 24.9 patient-years, respectively: the incidence was 11.3% per patient-years. The frequency of seizures due to intra-CCM hemorrhage as the primary symptom was significantly higher in the CCM-related epilepsy group than in the non-CCM-related epilepsy group (p = 0.01). Other clinical characteristics, i.e., primary symptoms including vomiting/nausea and spastic paralysis, magnetic resonance imaging findings, including the number or maximum diameter of CCMs, cortical involvement, intra-CCM hemorrhage, and infratentorial lesions, surgical resection, and non-epileptic sequelae, such as motor disability and intellectual disability, did not significantly differ between the groups.  Discussion: The incidence of CCM-related epilepsy in the present study was 11.3% per patient year, higher than in adults. This discrepancy may be attributed to these studies including both adult and pediatric patients, whereas the present study examined a pure pediatric population. The presence of seizures due to intra-CCM hemorrhage as the initial symptom was a risk factor for CCM-related epilepsy in the present study. To elucidate the pathophysiology of CCM-related epilepsy or the reason for its higher incidence in children than in adults, further analyses of a large number of children with CCM-related epilepsy are warranted.

Functional outcome after pediatric cerebral cavernous malformation surgery

The purpose of this study was to investigate the functional outcome following surgical resection of cerebral cavernous malformations (CCM) in pediatric patients. We screened our institutional database of CCM patients treated between 2003 and 2021. Inclusion regarded individuals younger or equal than 18 years of age with complete clinical baseline characteristics, magnetic resonance imaging dataset, and postoperative follow-up time of at least three months. Functional outcome was quantified using the modified Rankin Scale (mRS) score and assessed at admission, discharge, and last follow-up examination. The primary endpoint was the postoperative functional outcome. As a secondary endpoint, predictors of postoperative functional deterioration were assessed. A total of 49 pediatric patients with a mean age of 11.3 ± 5.7 years were included for subsequent analyses. Twenty individuals (40.8%) were female. Complete resection of the lesion was achieved in 44 patients (89.8%), and two patients with incomplete resection were referred for successive remnant removal. The mean follow-up time after surgery was 44 months (IQR: 13 - 131). The mean mRS score was 1.6 on admission, 1.7 at discharge, and 0.9 at the latest follow-up. Logistic regression analysis adjusted to age and sex identified brainstem localization (aOR = 53.45 [95%CI = 2.26 - 1261.81], p = .014) as a predictor of postoperative deterioration. This study indicates that CCM removal in children can be regarded as safe and favorable for the majority of patients, depending on lesion localization. Brainstem localization implies a high risk of postoperative morbidity and indication for surgery should be balanced carefully. Minor evidence indicates that second-look surgery for CCM remnants might be safe and favorable.

Reliability of Functional and Diffusion MR Imaging Near Cerebral Cavernous Malformations

BACKGROUND AND PURPOSE

Surgical resection of cerebral cavernous malformations close to eloquent regions frequently uses fMRI and DTI for surgical planning to best preserve neurologic function. This study investigates the reliability of fMRI and DTI near cerebral cavernous malformations.

MATERIALS AND METHODS

Consecutive patients with cerebral cavernous malformations undergoing presurgical fMRI and DTI mapping were identified. Each cerebral cavernous malformation was hand-contoured; 2 sequential 4-mm expansion shells (S1 and S2) were created, generating 2 ROIs and 2 contralateral controls. Fractional anisotropy and regional homogeneity measurements were then extracted from each ROI and compared with the contralateral controls. Reliability, accuracy, and precision were compared as appropriate.

RESULTS

Fifty-four patients were identified and included. Errors of fractional anisotropy were significantly lower than those of regional homogeneity in S1 and S2 (P < .001), suggesting that fractional anisotropy is more reliable than regional homogeneity near cerebral cavernous malformations. Proximity to cerebral cavernous malformations worsened the reliability of regional homogeneity (S1 versus S2, P < .001), but not fractional anisotropy (P = .24). While fractional anisotropy was not significantly biased in any ROI (P > .05), regional homogeneity was biased toward lower signals in S1 and S2 (P < .05), an effect that was attenuated with distance from cerebral cavernous malformations (P < .05). Fractional anisotropy measurements were also more precise than regional homogeneity in S1 and S2 (P < .001 for both).

CONCLUSIONS

Our findings suggest that hemosiderin-rich lesions such as cerebral cavernous malformations may lead to artifactual depression of fMRI signals and that clinicians and surgeons should interpret fMRI studies near cerebral cavernous malformations with caution. While fMRI is considerably affected by cerebral cavernous malformation-related artifacts, DTI appears to be relatively unaffected and remains a reliable imaging technique near cerebral cavernous malformations.

Clinical characteristics and risk factors of cerebral cavernous malformation-related epilepsy

PURPOSE

This study aimed to summarize the clinical characteristics and explore the risk factors for cerebral cavernous malformation (CCM)-related epilepsy (CRE).

METHODS

We retrospectively analyzed the clinical data of patients with CCM in our cerebral vascular malformations database. Descriptive statistics were used to present the clinical characteristics of CRE patients. Patients were divided into a CRE and a non-CRE group according to clinical presentation. Binary logistic regression analysis was used to analyze the risk factors of CRE.

RESULTS

A total of 199 patients with CCM confirmed by postoperative pathological examination were enrolled, 93 of whom were diagnosed with CRE, and 34 patients had drug-resistant epilepsy. The most common seizure type of CRE patients was focal to bilateral tonic-clonic seizure (FBTCS), followed by focal impaired awareness motor seizure. All CCM lesions were supratentorial, 97.8% of which involved the cerebral cortex, 86.0% of lesions had hemosiderin rim, and 50.5% of lesions were located in the temporal lobe. Binary logistic regression analysis indicated that CCM diagnosis age ≤ 44 years (odds ratio [OR] 2.79, p = 0.010), temporal lobe lesion location (OR = 9.07, p = 0.042), medial temporal lobe lesion (OR = 14.09, p = 0.002), cortical involvement of the lesion (OR = 32.77, p = 0.010), and hemosiderin rim around the lesion (OR = 16.48, p = 0.001) significantly increased the risk of CRE.

CONCLUSIONS

The most common seizure type of CRE was FBTCS. Those whose CCM diagnosis age was ≤ 44 years, having a temporal lobe lesion location, especially the medial temporal lobe lesion, cortical involvement, and hemosiderin rim around the lesion had a higher risk of developing CRE.

Medication intake and hemorrhage risk in patients with familial cerebral cavernous malformations

OBJECTIVE

The objective of this study was to analyze the impact of medication intake on hemorrhage risk in patients with familial cerebral cavernous malformation (FCCM).

METHODS

The authors' institutional database was screened for patients with FCCM who had been admitted to their department between 2003 and 2020. Patients with a complete magnetic resonance imaging (MRI) data set, evidence of multiple CCMs, clinical baseline characteristics, and follow-up (FU) examination were included in the study. The authors assessed the influence of medication intake on first or recurrent intracerebral hemorrhage (ICH) using univariate and multivariate logistic regression adjusted for age and sex. The longitudinal cumulative 5-year risk of hemorrhage was calculated by applying Kaplan-Meier and Cox regression analyses adjusted for age and sex.

RESULTS

Two hundred five patients with FCCMs were included in the study. Multivariate Cox regression analysis revealed ICH as a predictor for recurrent hemorrhage during the 5-year FU. The authors also noted a tendency toward a decreased association with ICH during FU in patients on statin medication (HR 0.22, 95% CI 0.03-1.68, p = 0.143), although the relationship was not statistically significant. No bleeding events were observed in patients on antithrombotic therapy. Kaplan-Meier analysis and log-rank test showed a tendency toward a low risk of ICH during FU in patients on antithrombotic therapy (p = 0.085), as well as those on statin therapy (p = 0.193). The cumulative 5-year risk of bleeding was 22.82% (95% CI 17.33%-29.38%) for the entire cohort, 31.41% (95% CI 23.26%-40.83%) for patients with a history of ICH, 26.54% (95% CI 11.13%-49.7%) for individuals on beta-blocker medication, 6.25% (95% CI 0.33%-32.29%) for patients on statin medication, and 0% (95% CI 0%-30.13%) for patients on antithrombotic medication.

CONCLUSIONS

ICH at diagnosis was identified as a risk factor for recurrent hemorrhage. Although the relationships were not statistically significant, statin and antithrombotic medication tended to be associated with decreased bleeding events.

[Cerebral and spinal cavernomas]

CLINICAL/METHODICAL ISSUE

Cavernous malformations or cavernomas belong to the angiodysplasias. They may be sporadic or familial and cause symptoms (epilepsy) despite the absence of a left-to-right shunt. In addition to intracranial locations, spinal cavernomas are also found.

STANDARD RADIOLOGICAL METHODS

Magnetic resonance imaging (MRI) and computed tomography (CT) are used for diagnosis PERFORMANCE: MRI, except for acutely or subacutely hemorrhaged cavernomas, is superior to CT for lesion detection.

ACHIEVEMENTS

CT is reserved for acute diagnosis. MRI, especially susceptibility-sensitive gradient echo sequences, can also detect cavernomas without (sub-)acute hemorrhage or calcifications.

PRACTICAL RECOMMENDATIONS

MRI is also useful for differentiating the familial form vs. sporadic form. Digital subtraction angiography (DSA) is used for differential diagnosis in rare cases, as cavernomas show no correlate here.

A Rare Case of Frontal Lobe Cavernous Malformation Mimicking Meningioma

Cavernous venous malformations are benign vascular lesions that commonly occur in the brain parenchyma. These when present in the extra-axial or superficial cortical location can be mistaken for meningioma. Magnetic resonance imaging (MRI) can help in the detection and easy differentiation of the two entities and thus aid in preoperative diagnosis and preventing intraoperative complications. We present a case of an 18-year-old male patient suffering from seizures, which was initially diagnosed as meningioma. However, detailed evaluation with MRI raised a possibility of cavernous malformation and it was considered as a differential.

Anatomo-functional evaluation for management and surgical treatment of insular cavernous malformation: a case series

BACKGROUND

Insular cavernous malformations (iCMs) are very rare vascular lesions. Their surgical management is challenging, due to their complex functional and vascular relationship. The continuous improvement of intra-operative tools and neuroimaging techniques has progressively enhanced the safety of iCM surgery. Nevertheless, the best surgical approach remains controversial.

OBJECTIVE

To analyze the potential role of an anatomo-functional classification to guide the iCMs' management.

METHODS

The study included patients affected by iCMs and referred to the Senior Author (FA). All cases were divided in 2 groups, according to a mainly pial growth pattern (exophytic group) or a subcortical one (endophytic group). Endophytic iCM was further subdivided in 3 subgroups, based on the insular gyri involved. According to this classification, each patient underwent a specific additional neuroimaging investigation and surgical evaluation.

RESULTS

A total of 24 patients were included. In the surgical group, trans-sylvian (TS) approach was used in 6 patients with exophytic or Zone I endophytic iCMs. The transcortical (TC) approach with awake monitoring was used in 6 cases of Zone II endophytic vascular lesions. Both TS and trans-intraparietal sulcal (TIS) approach were used for 3 cases of Zone III endophytic iCM. At follow-up, 3 patients were fully recovered from a transient speech impairment while a permanent morbidity was observed in one case.

CONCLUSIONS

ICMs represent a single entity with peculiar clinical and surgical aspects. The proposed iCM classification focuses on anatomical and functional concerns, aiming to suggest the best pre-operative work-up and the surgical evaluation.

Quality of life and mood assessment in conservatively treated cavernous malformation-related epilepsy

BACKGROUND

To estimate the quality of life, anxiety, depression, and illness perception in patients with medically treated cerebral cavernous malformation (CCM) and associated epilepsy.

METHODS

Nonsurgically treated patients with CCM-related epilepsy (CRE) were included. Demographic, radiographic, and clinical features were assessed. All participants received established questionnaires (short-form 36 health survey, SF-36; hospital anxiety and depression score, HADS-A/D; visual analogue scale score, VAS) assessing the functional and psychosocial burden of disease. To some extent, calculated values were compared with reference values from population-based studies. Test results were related to seizure control.

RESULTS

A total of 37 patients were included. Mean age was 45.8 ± 14.4 years, and 54.1% were female. Diagnosis of CRE was significantly associated with attenuated quality of life and increased level of anxiety, affecting physical and psychosocial dimensions. The assessment of illness perception identified considerable burden. HADS was significantly associated with VAS and SF-36 component scores. Efficacy of antiepileptic medication had no restoring impact on quality of life, anxiety, depression, or illness perception.

CONCLUSIONS

CRE negatively influences quality of life and mood, independent of seizure control due to antiepileptic medication. Screening for functional and psychosocial deficits in clinical practice might be useful for assessing individual burden and allocating surgical or drug treatment.

Strategic infarct location for post-stroke seizure

•

The hot spots of PSS were distributed around the central region of cerebral cortex.

•

We observed differences between the distribution of hot spots among patients with early-PSS and those with late-PSS.

•

The specific regions of the brain are significantly associated with the development of PSS after cerebral infarction.

•

The location of infarction could help clinicians assess the risk of PSS in specific post-stroke stages.

Post-stroke seizure (PSS) can have a strong negative impact on functional recovery after stroke. Researchers have identified numerous risk factors of PSS; however, the relationship between infarction location and PSS remains unclear. We recruited patients who presented with an acute cerebral infarction between 2012 and 2017 and suffered from seizures within 1 year after stroke (PSS group). PSS group was subgrouped into early-PSS and late-PSS groups based on the interval between seizure and stroke. We also recruited an equal number of acute cerebral infarction patients without post-stroke seizures during the follow-up period (Non-PSS group). All brain MRIs from the two groups were processed, whereupon normalized infarct maps from the PSS and Non-PSS groups were compared via voxel- and volumetric-based analyses. A total of 132 subjects were enrolled in the study, including PSS (n = 66, consisting of 31 early-PSS and 35 late-PSS) and Non-PSS (n = 66) patients. No significant differences were observed between the two groups in terms of stroke lateralization or severity. Image analysis revealed that the volume of infarction was larger in the PSS group than in the Non-PSS group; however, the difference did not reach the level of significance. Unlike the Non-PSS group, the PSS group presented hot spots over the left central region, left superior parietal lobule, and right frontal operculum. We observed differences between the distribution of hot spots among patients with early-PSS and those with late-PSS. We found that some brain regions were significantly associated with the development of PSS after ischemic stroke, and these regions differed between cases of early and late PSS. It appears that the location of infarction could help clinicians assess the risk of PSS in specific post-stroke stages.

Clinical characteristics and long-term outcome of cerebral cavernous malformations-related epilepsy

OBJECTIVE

Cerebral cavernous malformations (CCMs) present variably and epileptic seizures are the most common symptom. The factors contributing to cavernoma-related epilepsy (CRE) and drug resistance remain inconclusive. The outcomes of CRE after different treatment modalities have not yet been fully addressed. This study aimed to characterize the clinical features of patients with CRE and the long-term seizure outcomes of medical and surgical treatment strategies.

METHODS

This was a retrospective cohort of 135 patients with CCM who were diagnosed in 2007~2011 and followed up for 93.6 months on average. The patients were divided into drug-resistant epilepsy (DRE) (n = 29), non-DRE (NDRE) (n = 45), and no epilepsy (NE) (n = 61).

RESULTS

Temporal CCM was the factor most strongly associated with the development of both CRE and DRE. The majority of patients with single temporal CCMs had CRE (86.8%, n = 33) and 50% had DRE, whereas only 14.7% (n = 5) with a non-temporal supratentorial CCM had DRE (P < 0.05). The most common lesion site in the DRE group was the mesiotemporal lobe (50%). Multiple CCMs were more frequently observed in the CRE (29.2%) than the NE (11.5%) group (P < 0.05). In patients with CRE, multiple lesions were associated with a higher rebleeding rate (odds ratio: 11.1), particularly in those with DRE (odds ratio: 15.4). The majority of patients who underwent resective surgery for DRE (76.5%, n = 13) achieved ILAE class I and II seizure outcomes even after a long disease course.

SIGNIFICANCE

Temporal CCM not only predisposes to CRE but is also a major risk factor for drug resistance. The mesiotemporal lobe is the most epileptogenic zone. Multiple CCMs are another risk factor for CRE and increase the rebleeding risk in these patients. Surgical resection could provide beneficial long-term seizure outcomes in patients with DRE.

Management of pediatric cerebral cavernous malformations with gamma knife radiosurgery: a report of 46 cases

INTRODUCTION

Pediatric cerebral cavernous malformations (CCMs) are commonly treated vascular anomalies with different clinical characteristics than their adult counterparts. Outcomes of Gamma Knife Radiosurgery (GKRS) for pediatric CCMs have not explicitly been reported. This paper reports our experience in managing pediatric CCMs with GKRS.

METHODS

We retrospectively reviewed the clinical features, GKRS parameters, and clinical and radiological outcomes of 46 children with 64 CCMs.

RESULTS

A total of 46 children, including 19 girls and 27 boys, with a median age of 16 years (3-17 years), were enrolled in the study. The median age at first CCM diagnosis was 13 years (range, 2-17 years). Twenty-two patients (47.8%) had more than one neurological symptom at the time of diagnosis, and the most common presenting symptom was seizure (28.3%). The most common location was supratentorial superficial (53.1%), and 17.4% of patients had multiple CCMs. A developmental venous anomaly was detected in 5 patients (10.9%). During a total of 52.4 retrospective patient-years in patients with > 1 hemorrhage episode, the calculated annual hemorrhage rate was 40.1%. The median post-GKRS follow-up was 79 months (range, 19-175 months), with an overall 306.2 prospective patient years. The annual hemorrhage rate (AHR) during the first 2 years after GKRS and after the initial 2 years was 1.11% and 0.46%, respectively. Regarding clinical factors and GKRS parameters, univariate analysis revealed a significant association with post-GKRS AHR and volume (p = 0.023) only. Patients with pre-GKRS seizures showed favorable seizure control (Engel class I and II) in 8 children (61.5%). There was no mortality in our series.

CONCLUSION

Low AHR following GKRS with no radiation-induced toxicity makes GKRS a therapeutic alternative for pediatric CCMs.

Long-Term Management of Seizures after Surgical Treatment of Supratentorial Cavernous Malformations : A Retrospective Single Centre Study

Objective

Seizure recurrence after the first-ever seizure in patients with a supratentorial cerebral cavernous malformation (CCM) is almost certain, so the diagnosis and treatment of epilepsy is justified. The optimal method of management of these patients is still a matter of debate. The aim of our study was to identify factors associated with postoperative seizure control and assess the surgical morbidity rate.

Methods

We retrospectively analysed 45 consecutive patients with a supratentorial CCM and symptomatic epilepsy in a single centre. Pre- and postoperative epidemiological data, seizure-related patient histories, neuroimaging results, surgery details and outcomes were obtained from hospital medical records. Seizure outcomes were assessed at least 12 months after surgery.

Results

Thirty-five patients (77.8%) were seizure free at the long-term follow-up (Engel class I); six (13,3%) had rare, nocturnal seizures (Engel class II); and four (8.9%) showed meaningful improvement (Engel class III). In 15 patients (33%) in the Engel I group; it was possible to discontinue antiepileptic medication. Although there was not statistical significance, our results suggest that patients can benefit from early surgery. No deaths occurred in our study, and mild postoperative neurologic deficits were observed in two patients (4%) at the long-term follow-up.

Conclusion

Surgical resection of CCMs should be considered in all patients with a supratentorial malformation and epilepsy due to the favourable surgical results in terms of the epileptic seizure control rate and low postoperative morbidity risk, despite the use of different predictors for the seizure outcome.

Multimodal Presurgical Evaluation of Medically Refractory Focal Epilepsy in Adults: An Update for Radiologists

Surgery is a potentially curative treatment option for patients with medically refractory focal epilepsy. Advanced neuroimaging modalities often improve surgical outcomes by contributing key information during the highly individualized surgical planning process and intraoperative localization. Hence, neuroradiologists play an integral role as part of the multidisciplinary management team. In this review, we initially present the conceptual background and practical framework of the presurgical evaluation process, including a description of the surgical treatment approaches in medically refractory focal epilepsy in adults. This background is followed by an overview of the advanced modalities commonly used during the presurgical workup at level IV epilepsy centers including diffusion imaging techniques, blood oxygen level dependent (BOLD) functional MRI (fMRI), PET, SPECT, and subtraction ictal SPECT, as well as by introductions to 7-T MRI and electrophysiologic techniques including electroencephalography (EEG) and magnetoencephalography (MEG). We also provide illustrative case examples of multimodal neuroimaging including PET/MRI, PET/MRI-DTI, subtraction ictal SPECT, and image-guided stereotactic planning with fMRI-DTI.

Neuroimaging of Epilepsy

PURPOSE OF REVIEW

This article provides an overview of imaging modalities, important imaging pathologies, and the role each imaging modality can play in the diagnosis, evaluation, and treatment of epilepsy, including epilepsy surgery.

RECENT FINDINGS

The Harmonized Neuroimaging of Epilepsy Structural Sequences (HARNESS-MRI) protocol was proposed to standardize MRI imaging for all patients with seizures. The role of 7-Tesla MRI in finding previously occult epileptogenic lesions is under investigation, and the technique is increasingly used. Developing MRI postprocessing techniques can increase the sensitivity of MRI. Improvements in functional imaging techniques such as EEG-functional MRI (fMRI) and magnetic source imaging provide complementary methods of identifying seizure foci. New epileptogenic pathologies such as multinodular and vacuolating neuronal tumors (MVNT) are being discovered, and the importance of others, such as encephaloceles, is better appreciated.

SUMMARY

Brain imaging is a critical component of the diagnosis and evaluation of patients with epilepsy. Structural imaging modalities such as MRI and CT allow for the identification of a wide variety of potentially epileptogenic lesions. For patients with drug-resistant epilepsy under consideration for resective surgery, both structural and functional neuroimaging may be needed for focus identification and surgical planning for preservation of neurologic function.

Levetiracetam-Induced Psychosis in the Setting of Intracranial Cavernomas

Levetiracetam is a commonly used antiepileptic medication that has been associated with the development of psychosis. Cavernomas are vascular malformations that have been associated with psychosis as well, especially in the setting of hemorrhagic transformation. This case report describes a patient with cavernomas who developed psychotic symptoms after restarting her levetiracetam at a high dose (2000 mg twice a day) without gradual uptitration. Her symptoms improved upon the reduction of the levetiracetam as well as the initiation of paliperidone. This case highlights the importance of considering the biologic and medication-related factors for the development of psychosis, as well as the importance of gradual medication adjustments.

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.

Role of i-CT, i-US, and Neuromonitoring in Surgical Management of Brain Cavernous Malformations and Arteriovenous Malformations: A Case Series

OBJECTIVE

We retrospectively reviewed the institutional experience in patients who underwent microsurgical resection of cavernous malformations (CMs) or arteriovenous malformations (AVMs) using a multimodal intraoperative protocol including neuronavigation, intraoperative ultrasound (i-US), computed tomography (i-CT), and neuromonitoring.

METHODS

Twenty-four patients (14 male), with a mean age of 47.5 years (range 27-73), have been included: 20 of them suffered from CMs and 4 suffered from AVMs. Neuromonitoring was used in 18 cases, when lesions were located in eloquent areas; 2 patients underwent awake craniotomy. First, an i-CT scan with and without contrast was acquired after patient positioning. Navigated B-mode ultrasound acquisition was carried out after dural opening to identify the lesion (CMs or AVMs nidus). Following identification and resection of vascular lesions, postcontrast i-CT (or CT-angio) was performed to detect and localize any small or calcified remnant (in cases of CMs) or residual vessels feeding the nidus (in cases of AVMs).

RESULTS

In 5 cases of CMs and in 1 case of AVM, i-CT identified small residual lesions. In these cases, new i-CT images were uploaded into the navigation system and used for further resection. i-US was useful before starting transsulcal or transcortical approach to identify the lesions and guide the trajectory of the approach. However, several artifacts were observed during subsequent steps of dissection, making image interpretation difficult.

CONCLUSIONS

The combination of different intraoperative real-time imaging modalities (i-CT and i-US), coupled with neuromonitoring, in the surgical management of vascular lesions, particularly if located in eloquent areas, has a positive impact on clinical outcome.

Variable histopathology features of neuronal dyslamination in the cerebral neocortex adjacent to epilepsy-associated vascular malformations suggest complex pathogenesis of focal cortical dysplasia ILAE type IIIc

Focal cortical dysplasia type IIIc (FCD‐IIIc) is histopathologically defined by the International League Against Epilepsy's classification scheme as abnormal cortical organization adjacent to epilepsy‐associated vascular malformations (VM). However, the incidence of FCD‐IIIc, its pathogenesis, or association with the epileptogenic condition remains to be clarified. We reviewed a retrospective series of surgical brain specimens from 14 epilepsy patients with leptomeningeal angiomatosis of Sturge‐Weber syndrome (LMA‐SWS; n = 6), cerebral cavernous malformations (CCM; n = 7), and an arteriovenous malformation (AVM; n = 1) to assess the histopathological spectrum of FCD‐IIIc patterns in VM. FCD‐IIIc was observed in all cases of LMA‐SWS and was designated as cortical pseudolaminar sclerosis (CPLS). CPLS showed a common pattern of horizontally organized layer abnormalities, including neuronal cell loss and astrogliosis, either manifesting predominantly in cortical layer (L) 3 extending variably to deeper areas with or without further extension to L2 and/or L4. Another pattern was more localized, targeting mainly L4 with extension to L3 and/or L5. Abnormal cortical layering characterized by a fusion of L2 and L3 or L4–L6 was also noted in two LMA‐SWS cases and the AVM case. No horizontal or vertical lamination abnormalities were observed in the specimens adjacent to the CCM, despite the presence of vascular congestion and dilated parenchymal veins in all VM. These findings suggest that FCD‐IIIc depends on the type of the VM and developmental timing. We further conclude that FCD‐IIIc represents a secondary lesion acquired during pre‐ and/or perinatal development rather than following a pathomechanism independent of LMA‐SWS. Further studies will be necessary to address the selective vulnerability of the developing cerebral neocortex in LMA‐SWS, including genetic, encephaloclastic, hemodynamic, or metabolic events.

How can we optimize the long-term outcome in children with intracranial cavernous malformations? A single-center experience of 61 cases

The objective is to provide a treatment algorithm for pediatric patients with intracranial cavernous malformations (CMs) based on our experience. Patients < 18 years of age who were treated either surgically or conservatively at the authors' institution between 1982 and 2019 were retrospectively evaluated. A total of 61 pediatric patients were treated at the authors' institution: 39 with lobar CMs; 18 with deep CMs, including 12 in the brainstem and 6 in the basal ganglia; and 4 with CMs in the cerebellar hemispheres. Forty-two patients underwent surgery, and 19 were treated conservatively. The median follow-up time was 65 months (1-356 months). In surgically treated patients, lesions were larger (2.4 cm vs 0.9 cm, p < 0.001). In patients with lobar CMs, seizures were more common (72% vs 21%, p = 0.003) in the surgery group than in conservatively managed patients. In deep CMs, modified Rankin scale (mRS) was higher (4 vs 1, p = 0.003) in the surgery group than in conservatively treated patients. At the time of last follow-up, no differences in Wieser outcome class I were seen (86% vs 67%) in lobar CMs, and mRS scores had aligned between the treatment groups in deep CMs (1 vs 0). We encountered no new permanent neurological deficit at time of last follow-up. We propose a treatment algorithm according to lesion location and size, burden of symptoms, epilepsy workup, and further clinical course during observation. A conservative management is safe in pediatric patients with asymptomatic CMs. Gross total resection should be the aim in patients with symptomatic lobar CMs. A less aggressive approach with subtotal resection, when required to prevent neurological compromise, sustainably improves neurological outcome in patients with deep CMs.

Semiology, EEG, and neuroimaging findings in temporal lobe epilepsies

Temporal lobe epilepsy (TLE) is the most common type of focal epilepsy. First descriptions of TLE date back in time and detailed portraits of epileptic seizures of temporal origin can be found in early medical reports as well as in the works of various artists and dramatists. Depending on the seizure onset zone, several subtypes of TLE have been identified, each one associated with peculiar ictal semiology. TLE can result from multiple etiological causes, ranging from genetic to lesional ones. While the diagnosis of TLE relies on detailed analysis of clinical as well as electroencephalographic (EEG) features, the lesions responsible for seizure generation can be highlighted by multiple brain imaging modalities or, in selected cases, by genetic investigations. TLE is the most common cause of refractory epilepsy and despite the great advances in diagnostic tools, no lesion is found in around one-third of patients. Surgical treatment is a safe and effective option, requiring presurgical investigations to accurately identify the seizure onset zone (SOZ). In selected cases, presurgical investigations need intracerebral investigations (such as stereoelectroencephalography) or dedicated metabolic imaging techniques (interictal PET and ictal SPECT) to correctly identify the brain structures to be removed.

Displacement of Gray Matter and Incidence of Seizures in Patients with Cerebral Cavernous Malformations

Seizures are the most common presentation in patients with cerebral cavernous malformations (CCMs). Based on the hypothesis that the volume or proportion of gray matter (GM) displaced by CCMs is associated with the risk of seizure, we developed an algorithm by which to quantify the volume and proportion of displaced GM and the risk of seizure. Image analysis was conducted on 111 patients with solitary CCMs (divided into seizure and nonseizure groups) from our gamma knife radiosurgery (GKRS) database from February 2005 and March 2020. The CCM algorithm proved effective in quantifying the GM and CCM using T1WI MRI images. In the seizure group, 11 of the 12 patients exhibited seizures at the initial presentation, and all CCMs in the seizure group were supratentorial. The location of the limbic lobe within the CCM was significantly associated with the risk of seizure (OR = 19.6, p = 0.02). The risk of seizure increased when the proportion of GM displaced by the CCM exceeded 31%. It was also strongly correlated with the volume of displaced GM. The volume and proportion of displaced GM were both positively correlated with the risk of seizure presentation/development and thus could be used to guide seizure prophylaxis in CCM patients.

Impacting the Treatment of Highly Eloquent Supratentorial Cerebral Cavernous Malformations by Noninvasive Functional Mapping-An Observational Cohort Study

BACKGROUND

Cerebral cavernous malformations (CCM) may cause cavernoma-related epilepsy (CRE) and intracranial hemorrhage (ICH). Functional mapping has shown its usefulness during the resection of eloquent lesions including the treatment of brain arteriovenous malformations.

OBJECTIVE

To evaluate the impact of noninvasive functional mapping on decision-making and resection of eloquently located CCM.

METHODS

Of 126 patients with intracranial cavernomas, we prospectively included 40 consecutive patients (31.7%) with highly eloquent CCM between 2012 and 2020. We performed functional mapping via navigated transcranial magnetic stimulation (nTMS) motor mapping in 30 cases and nTMS language mapping in 20 cases. Twenty patients suffered from CRE. CCM caused ICH in 18 cases.

RESULTS

We used functional mapping data including function-based tractography in all cases. Indication toward (31 cases) or against (9 cases) CCM resection was influenced by noninvasive functional mapping in 36 cases (90%). We resected CCMs in 24 cases, and 7 patients refused the recommendation for surgery. In 19 and 4 cases, we used additional intraoperative neuromonitoring and awake craniotomy, respectively. Patients suffered from transient postoperative motor or language deficits in 2 and 2 cases, respectively. No patient suffered from permanent deficits. After 1 yr of follow-up, anti-epileptic drugs could be discontinued in all patients who underwent surgery but 1 patient.

CONCLUSION

Surgery-related deficit rates are low even for highly eloquent CCM and seizure outcome is excellent. The present results show that noninvasive functional mapping and function-based tractography is a useful tool for the decision-making process and during microsurgical resection of eloquently located CCM.

Seizure Incidence Rates in Children and Adults With Familial Cerebral Cavernous Malformations

BACKGROUND AND OBJECTIVES

Seizure incidence rates related to familial cerebral cavernous malformation (FCCM) are not well described, especially for children. To measure the seizure incidence rate, examine seizure predictors, and characterize epilepsy severity, we studied a cohort of children and adults with FCCM enrolled in the Brain Vascular Malformation Consortium (BVMC).

METHODS

Seizure data were collected from participants with FCCM in the BVMC at enrollment and during follow-up. We estimated seizure probability by age and tested whether cerebral cavernous malformation (CCM) counts or genotype were associated with earlier seizure onset.

RESULTS

The study cohort included 479 FCCM cases. Median age at enrollment was 42.5 years (interquartile range 22.5-55.0) and 19% were children (<18 years old). Median large CCM count was 3 (interquartile range 1-5). Among 393 with genotyping, mutations were as follows: CCM1 (Common Hispanic Mutation) (88%), another CCM1 mutation (5%), CCM2 mutations (5%), and CCM3 mutations (2%). Prior to or during the study, 202 (42%) had a seizure. The cumulative incidence of a childhood seizure was 20.3% (95% confidence interval [CI] 17.0-23.4) and by age 80 years was 60.4% (95% CI 54.2-65.7). More total CCMs (hazard ratio [HR] 1.24 per SD unit increase, 95% CI 1.1-1.4) or more large CCMs (HR 1.5 per SD unit increase, 95% CI 1.2-1.9) than expected for age and sex increased seizure risk. A CCM3 mutation also increased risk compared to other mutations (HR 3.11, 95% CI 1.15-8.45). Individuals with a seizure prior to enrollment had increased hospitalization rates during follow-up (incidence rate ratio 10.9, 95% CI 2.41-49.32) compared to patients without a seizure history.

DISCUSSION

Individuals with FCCM have a high seizure incidence and those with more CCMs or CCM3 genotype are at greater risk. Seizures increase health care utilization in FCCM.

Tuberous sclerosis with negative genetic testing and multiple cerebral cavernomas: A new association (Case report)

Tuberous sclerosis complex (TSC) is an autosomal dominant disorder with multisystemic involvement usually resulting from mutations in the tuberous sclerosis 1 (TSC1) or TSC2 genes. However, 10 to 25% of patients do not exhibit these mutations. Cerebral cavernous malformations (CCMs) are capillary-venous malformations that can be asymptomatic or cause variable neurological manifestations, including seizures. Familial CCMs are recognized. In both conditions, specific dermatological lesions are associated. We present the case of a 31-year-old female with TSC diagnosed at the age of 18 years who presented with negative genetic testing. She was admitted to our department in 2019 for a sudden increased frequency of focal seizures. Patient examination revealed multiple facial and intraoral angiofibroma, diplopia, right hemihypoesthesia, brisk deep tendon reflexes, and distal leg paresthesia. VideoEEG indicated a frontal paramedian epileptogenic focus. Cerebral magnetic resonance imaging (MRI) and angioMRI identified multiple fronto-parietal cortical tubers, as well as multiple CCMs, with evidence of bleeding in one. Under antiepileptic drug (AED) and mTOR inhibitor treatment, the seizure frequency significantly improved in a short period of time. This is the first reported case of tuberous sclerosis with negative genetic testing associated with multiple cerebral cavernoma. Such complex patients require multidisciplinary management and detailed genetic testing for increasing knowledge on neuro-cutaneous disorders.

Reactive astrocytes contribute to epileptogenesis in patients with cavernous angioma

OBJECTIVE

Patients with cavernous angioma (CA) often suffer from severe epilepsy, and surgical resection is often performed to attenuate these epileptic seizures. Several studies have suggested that surgical removal of the surrounding hemosiderin-pigmented tissues adjacent to CA achieves better seizure control than restricted lesionectomy. Pathological examination of the resected foci reveals not only hemosiderin pigmentation but also various degrees of inflammatory change, such as hemosiderin-laden macrophages, gliosis and fibrosis. However, there is some controversy regarding the epileptogenic potential of these regions due to the uncertain nature of the mechanisms contributing to these histopathological changes.

METHODS

To investigate the correlations between neuron hyperexcitability and evident pathological changes, we performed ex vivo flavoprotein fluorescence imaging using surgically resected epileptogenic foci surrounding CA. The mirror surfaces of the tissues used for the physiological experiment were also subjected to morphological examination.

RESULTS

Hemosiderin-laden macrophages and many gemistocytic astrocytes were observed in the area adjacent to CA, where horizontal spreading excitations were detected significantly more frequently. Outside these areas, we found fine granular iron deposits and only a few fibrillary astrocytes, and weakly propagating excitations were detected. Furthermore, areas of enhanced activation were more clearly correlated with the glial proliferation index than with iron deposition.

CONCLUSION

These results suggest that the epileptogenesis in patients with CA may be based on a biological process, such as alteration of glial function, rather than direct chemical reactions involving iron deposition.

Feasibility and Morbidity of Magnetic Resonance Imaging-Guided Stereotactic Laser Ablation of Deep Cerebral Cavernous Malformations: A Report of 4 Cases

BACKGROUND

Magnetic resonance imaging (MRI)-guided laser interstitial thermal therapy (MRgLITT) has been used successfully to treat epileptogenic cortical cerebral cavernous malformations (CCM). It is unclear whether MRgLITT would be as feasible or safe for deep CCMs.

OBJECTIVE

To describe our experience with MRgLITT for symptomatic deep CCMs.

METHODS

Patients' records were reviewed retrospectively. MRgLITT was carried out using a commercially available system in an interventional MRI suite with efforts to protect adjacent brain structures. Immediate postoperative imaging was used to judge ablation adequacy. Delayed postoperative MRI was used to measure lesion volume changes during follow-up.

RESULTS

Four patients with CCM in the thalamus, putamen, midbrain, or subthalamus presented with persistent and disabling neurological symptoms. A total of 2 patients presented with disabling headaches and sensory disturbances and 2 with recurrent symptomatic hemorrhages, of which 1 had familial CCM. Patients were considered by vascular neurosurgeons to be poor candidates for open surgery or had refused it. Multiple trajectories were used in most cases. Adverse events included device malfunction with leakage of saline causing transient mass effect in one patient, and asymptomatic tract hemorrhage in another. One patient suffered an expected mild but persistent exacerbation of baseline deficits. All patients showed improvement from a previously aggressive clinical course with lesion volume decreased by 20% to 73% in follow-up.

CONCLUSION

MRgLITT is feasible in the treatment of symptomatic deep CCM but may carry a high risk of complications without the benefit of definitive resection. We recommend cautious patient selection, low laser power settings, and conservative temperature monitoring in surrounding brain parenchyma.

Surgery for cerebral cavernous malformations: a systematic review and meta-analysis

BACKGROUND

We sought to quantify the risks of neurosurgical excision of cerebral cavernous malformations (CCMs) in a systematic review of cohort studies.

METHODS

We updated our previous systematic review by searching OVID Medline, OVID EMBASE, and the Cochrane Library from 1 January 2013 to 30 April 2019. The primary outcome was a composite of death attributed to CCM or surgery, non-fatal symptomatic intracerebral haemorrhage (ICH), or new or worsened persistent non-haemorrhagic focal neurological deficit (FND).

RESULTS

We included 70 cohorts, 67 reporting surgery alone, and three compared surgery to conservative management. A total of 5,089 patients (median age 36 years, 52% female) underwent surgery (total follow-up 19,404 patient-years). The annual rate of the composite outcome was 4.2% (95% CI 2.9 to 5.7; 46 cohorts; I² = 93%), which was higher in cohorts reporting exclusively brainstem CCM (6.0%, 95% CI 4.1-8.3; 25 cohorts, I² = 92%) versus predominantly supratentorial CCM (2.4%, 95% CI 1.3-3.8, 21 cohorts, I² = 86%, p_het = 0.001). The annual rate of the composite outcome was higher in cohorts with > 95% presenting with ICH (6.1%, 95% CI 4.2-8.4; 23 cohorts, I² = 93%) versus others (2.3%, 95% CI 1.2-3.7; 23 cohorts, I² = 83%, p_het = 0.001). The incidence of the composite outcome did not change over time in cohorts of exclusively brainstem CCM (p = 0.7) or predominantly supratentorial CCM (p = 0.5).

CONCLUSIONS

The risk of death, ICH, or FND after CCM excision is ~ 4%. This risk is higher for brainstem CCM and CCM that have caused ICH but has not changed over time.

TRIAL REGISTRATION

This systematic review was registered (PROSPERO CRD42019131246).

A minority of patients with functional seizures have abnormalities on neuroimaging

OBJECTIVE

Functional seizures often are managed incorrectly as a diagnosis of exclusion. However, a significant minority of patients with functional seizures may have abnormalities on neuroimaging that typically are associated with epilepsy, leading to diagnostic confusion. We evaluated the rate of epilepsy-associated findings on MRI, FDG-PET, and CT in patients with functional seizures.

METHODS

We studied radiologists' reports from neuroimages at our comprehensive epilepsy center from a consecutive series of patients diagnosed with functional seizures without comorbid epilepsy from 2006 to 2019. We summarized the MRI, FDG-PET, and CT results as follows: within normal limits, incidental findings, unrelated findings, non-specific abnormalities, post-operative study, epilepsy risk factors (ERF), borderline epilepsy-associated findings (EAF), and definitive EAF.

RESULTS

Of the 256 MRIs, 23% demonstrated ERF (5%), borderline EAF (8%), or definitive EAF (10%). The most common EAF was hippocampal sclerosis, with the majority of borderline EAF comprising hippocampal atrophy without T2 hyperintensity or vice versa. Of the 87 FDG-PETs, 26% demonstrated borderline EAF (17%) or definitive EAF (8%). Epilepsy-associated findings primarily included focal hypometabolism, especially of the temporal lobes, with borderline findings including subtle or questionable hypometabolism. Of the 51 CTs, only 2% had definitive EAF.

SIGNIFICANCE

This large case series provides further evidence that, while uncommon, EAF are seen in patients with functional seizures. A significant portion of these abnormal findings are borderline. The moderately high rate of these abnormalities may represent framing bias from the indication of the study being "seizures," the relative subtlety of EAF, or effects of antiseizure medications.

An international call for a new grading system for cerebral and cerebellar cavernomas

Surgical indications for cerebral cavernous malformations remain significantly center- and surgeon-dependent. Available grading systems are potentially limited, as they do not include epileptological and radiological data. A novel grading system is proposed for supratentorial and cerebellar cavernomas: it considers neuroradiological features (bleeding, increase in size), neurological status (focal deficits and seizures), location of the lesion and age of the patient. The score ranges from -1 to 10; furthermore, surgery should be considered when a score of 4 or higher is present. Based on neuroradiological characteristics, 0 points are assigned if the CCM is stable in size at different neuroradiological controls, 1 point if there is an increase in volume during follow-up, 2 points if intra- or extra-lesional bleeding <1 cm is present and 3 points if the CCM produced a hematoma >1 cm. Regarding focal neurological deficits, 0 points are assigned if absent and 2 points if present. For seizures, 0 points are assigned if absent, 1 point if present, but controlled by medications, and 2 points if drug resistant. We considered the site of the CCM, and in case of deep-seated lesions in a critical area (basal ganglia, thalamus) 1 point (-1) is subtracted, while for subcortical or deep cerebellar lesions 0 points are assigned, for CCMs in a cortical critical area 1 point is assigned and in case of lesions in cortical not in critical area or superficial cerebellar area, 2 points are assigned. As far as age is concerned, 0 points are assigned for patients older than 50 years and 1 point for patients younger than 50. In conclusion, a novel grading for surgical decision making in cerebral cavernomas, based on the experience of selected neurosurgeons, basic scientists, and patients, is suggested with the aim of further improving and standardizing the treatment of CCMs. The aim of this paper was also to call for both retrospective and prospective multicenter studies with the aim of testing the efficacy of the grading system in different centers.