Seizures associated with cerebral arteriovenous malformations

Risk factors of seizure presentation in brain arteriovenous malformation patients and seizure outcomes after single-modality treatments

BACKGROUND

Epileptic seizures are common symptoms in brain arteriovenous malformation patients and seizure control was an important issue in the treatments. This retrospective study attempted to define the risk factors of seizure presentation and to evaluate the effects of treatment modalities on seizure outcomes.

METHODS

Patients receiving single treatment modality during 2013-2016 years, followed up more than 2 years were recruited. Logistic regression analysis was used to detect independent predictors. The factors associated with seizure control were analyzed in patients with pre-treatment seizures, and the factors associated with de novo seizures were analyzed in patents without pre-treatment seizures.

RESULTS

Multivariate analysis identified that the independent predictors of seizure presentation were unruptured (ruptured vs. unruptured, OR = 0.314), and in the frontal (frontal vs. parietal, OR = 3.982) or temporal lobe (temporal vs parietal, OR = 3.313). In 47 patients with seizure presentation, good seizure outcomes were achieved in 26 cases. Partial obliteration of nidus (partial vs complete, OR = 32.301) and headache presentation were independent predictors of poor outcome. In 169 patients without seizure presentation, de novo seizures occurred in 22 cases. Treatments of microsurgery or radiosurgery led to a higher incidence of de novo seizures than intravascular embolization.

CONCLUSIONS

Patients with unruptured and frontal/temporal lobe located nidus were more likely to manifest seizure presentation. Incomplete nidus obliteration was an independent risk factor of poor outcomes in patients with pre-existing seizures. However, compared to microsurgery or radiosurgery, endovascular embolization was less likely to cause de novo seizures in patients without pre-existing seizures.

New approaches for brain arteriovenous malformations-related epilepsy

BACKGROUND

The purpose of this review is to present the current literature and to highlight the most recent findings in brain arteriovenous malformations (bAVM)-related epilepsy research.

METHODS

We searched Medline, PubMed, Biblioinserm, Cochrane Central to study the latest research reports about the different factors that could be responsible for the genesis of bAVM-related epilepsy. We analyzed if epileptogenesis has any characteristics traits and its relation with the vascular malformation. The results of different treatments on epilepsy were considered. Typical errors that may lead towards incorrect or worse management of the seizures for these patients were also examined.

RESULTS

The development of bAVM results from multifactorial etiologies and bAVM-related epileptogenesis is likely specific for this pathology. Different types of evidence demonstrate a bidirectional relationship between bAVM and epilepsy. Currently, there is not enough published data to determine what may be the right management for these patients.

CONCLUSIONS

A better understanding of epileptogenesis in conjunction with knowledge of the complex alterations of structures and functions following bAVM-related seizures is necessary. Identification of biomarkers that can identify subgroups most likely to benefit from a specific intervention are needed to help guide clinical management. A new concept for the treatment of epilepsy related to an unruptured bAVM that cannot be treated invasively is proposed as well as new therapeutic perspectives. The next necessary step will be to propose additional algorithms to improve the development of future trials.

Brain magnetic resonance imaging findings among children with epilepsy in two urban hospital settings, Kampala-Uganda: a descriptive study

Background

Epilepsy is one of the most common neurological conditions in children worldwide. Its presentation is heterogeneous, with diverse underlying aetiology, clinical presentation, and prognosis. Structural brain abnormalities are among the recognized causes of epilepsy. Brain Magnetic Resonance Imaging (MRI) is the imaging modality of choice for epilepsy workup.

We aimed to determine the prevalence and describe the structural abnormalities identified in the brain MRI studies performed on children with epilepsy from two urban hospitals in Kampala, Uganda.

Methods

This was a cross-sectional descriptive study performed at two urban hospital MRI centres. The study population was 147 children aged 1 day to 17 years with confirmed epilepsy. Brain MRI was performed for each child and a questionnaire was used to collect clinical data.

Results

The prevalence of structural abnormalities among children with epilepsy was 74.15% (109 out of 147). Of these, 68.81% were male, and the rest were female. Among these, the majority, 40.14% (59 of 144) were aged 1 month to 4 years. Acquired structural brain abnormalities were the commonest at 69.22% with hippocampal sclerosis (HS) leading while disorders of cortical development were the most common congenital causes.

An abnormal electroencephalogram (EEG) was significant for brain MRI abnormalities among children with epilepsy with 95% of participants with an abnormal EEG study having epileptogenic structural abnormalities detected in their brain MRI studies.

Conclusion and recommendation

Two-thirds of children with epilepsy had structural brain abnormalities. Abnormal activity in the EEG study was found to positively correlate with abnormal brain MRI findings. As such, EEG study should be considered where possible before MRI studies as a determinant for children with epilepsy who will be having imaging studies done in the Ugandan setting.

De novo epilepsy after microsurgical resection of brain arteriovenous malformations

OBJECTIVE

Seizures are the second most common presenting symptom of brain arteriovenous malformations (bAVMs) after hemorrhage. Risk factors for preoperative seizures and subsequent seizure control outcomes have been well studied. There is a paucity of literature on postoperative, de novo seizures in initially seizure-naïve patients who undergo resection. Whereas this entity has been documented after craniotomy for a wide variety of neurosurgically treated pathologies including tumors, trauma, and aneurysms, de novo seizures after bAVM resection are poorly studied. Given the debilitating nature of epilepsy, the purpose of this study was to elucidate the incidence and risk factors associated with de novo epilepsy after bAVM resection.

METHODS

A retrospective review of patients who underwent resection of a bAVM over a 15-year period was performed. Patients who did not present with seizure were included, and the primary outcome was de novo epilepsy (i.e., a seizure disorder that only manifested after surgery). Demographic, clinical, and radiographic characteristics were compared between patients with and without postoperative epilepsy. Subgroup analysis was conducted on the ruptured bAVMs.

RESULTS

From a cohort of 198 patients who underwent resection of a bAVM during the study period, 111 supratentorial ruptured and unruptured bAVMs that did not present with seizure were included. Twenty-one patients (19%) developed de novo epilepsy. One-year cumulative rates of developing de novo epilepsy were 9% for the overall cohort and 8.5% for the cohort with ruptured bAVMs. There were no significant differences between the epilepsy and no-epilepsy groups overall; however, the de novo epilepsy group was younger in the cohort with ruptured bAVMs (28.7 ± 11.7 vs 35.1 ± 19.9 years; p = 0.04). The mean time between resection and first seizure was 26.0 ± 40.4 months, with the longest time being 14 years. Subgroup analysis of the ruptured and endovascular embolization cohorts did not reveal any significant differences. Of the patients who developed poorly controlled epilepsy (defined as Engel class III–IV), all had a history of hemorrhage and half had bAVMs located in the temporal lobe.

CONCLUSIONS

De novo epilepsy after bAVM resection occurs at an annual cumulative risk of 9%, with potentially long-term onset. Younger age may be a risk factor in patients who present with rupture. The development of poorly controlled epilepsy may be associated with temporal lobe location and a delay between hemorrhage and resection.

Predictors of seizure control in patients with cerebral arteriovenous malformation

PURPOSE

We aimed to define the predictors of a 2-year seizure-free outcome among patients with cerebral arteriovenous malformation (AVM).

METHODS

A retrospective cohort study recruited patients diagnosed with AVM admitted in the hospital between 2002 and 2020. The demographic data, clinical presentations, seizure semiology, neuro-imaging findings, modality of treatment, and clinical outcomes were compared between the 2-year seizure-free and non-2-year seizure-free groups. A logistic regression model was applied to determine the significant predictors of a 2-year seizure-free outcome.

RESULTS

Of 372 radiologically confirmed patients with cerebral AVM, 105 (28.23%) experienced seizure and a 2-year seizure-free outcome was achieved in 76.19%. Most seizures presented as the initial symptom. Generalized onset seizure was the most common seizure semiology. A nidus diameter < 3 cm (adjusted odds ratio [aOR] 3.102; 95% CI 1.129-9.683; p = 0.046) was the independent predictor of a 2-year seizure-free period, whereas underlying epilepsy (aOR 0.141; 95% CI 0.010-0.688; p = 0.015) was an independent predictor against a 2-year seizure-free outcome.

CONCLUSION

A nidus diameter < 3 cm was the independent predictor of a 2-year seizure-free outcome, whereas underlying epilepsy was the factor against a 2-year seizure-free outcome.

Radiomics Analysis for Predicting Epilepsy in Patients With Unruptured Brain Arteriovenous Malformations

Objectives: To investigate the association between radiomics features and epilepsy in patients with unruptured brain arteriovenous malformations (bAVMs) and to develop a prediction model based on radiomics features and clinical characteristics for bAVM-related epilepsy.

Methods: This retrospective study enrolled 176 patients with unruptured bAVMs. After manual lesion segmentation, a total of 858 radiomics features were extracted from time-of-flight magnetic resonance angiography (TOF-MRA). A radiomics model was constructed, and a radiomics score was calculated. Meanwhile, the demographic and angioarchitectural characteristics of patients were assessed to build a clinical model. Incorporating the radiomics score and independent clinical risk factors, a combined model was constructed. The performance of the models was assessed with respect to discrimination, calibration, and clinical usefulness.

Results: The clinical model incorporating 3 clinical features had an area under the curve (AUC) of 0.71. Fifteen radiomics features were used to build the radiomics model, which had a higher AUC of 0.78. Incorporating the radiomics score and clinical risk factors, the combined model showed a favorable discrimination ability and calibration, with an AUC of 0.82. Decision curve analysis (DCA) demonstrated that the combined model outperformed the clinical model and radiomics model in terms of clinical usefulness.

Conclusions: The radiomics features extracted from TOF-MRA were associated with epilepsy in patients with unruptured bAVMs. The radiomics-clinical nomogram, which was constructed based on the model incorporating the radiomics score and clinical features, showed favorable predictive efficacy for bAVM-related epilepsy.

Intracranial Gorgon: Surgical Case Report of a Large Calcified Brain Arteriovenous Malformation

Patient: Male, 55-year-old

Final Diagnosis: Right frontal arteriovenous malformation, partially calcified • multiple generalised epileptic seizures • chronic headache

Symptoms: Epilectic seizure • headache

Medication: —

Clinical Procedure: Neurosurgical resection of the right frontal AVM

Specialty: Neurosurgery

Volume-Staged CyberKnife Stereotactic Radiosurgery for Treatment of Drug-Resistant Epilepsy for a Spetzler-Martin Grade V Arteriovenous Malformation: A Case Report and Review of the Literature

BACKGROUND

Evidence to support the use of stereotactic radiosurgery (SRS) in the treatment of epilepsy secondary to cerebral arteriovenous malformations (AVMs) is emerging. However, these studies have not clearly demonstrated the use of SRS in the treatment of drug-resistant epilepsy (DRE) in high Spetzler-Martin grade (IV-V) AVMs.

CASE DESCRIPTION

We present a 48-year-old woman with DRE secondary to a Spetzler-Martin grade V cerebral AVM. She was treated with volume-staged SRS (VS-SRS) and achieved near-complete resolution of her seizures with incomplete obliteration of the AVM. Six years after treatment, she has experienced no serious complications.

CONCLUSIONS

VS-SRS successfully controlled seizures (Engel Outcome Measure of 1A) in a patient with intractable, DRE secondary to a high-grade cerebral AVM.