Risk Factors for Epilepsy Recurrence after Revascularization in Pediatric Patients with Moyamoya Disease

Predictive Factors for Seizures after Revascularization in Patients with Moyamoya Disease

BACKGROUND

Moyamoya disease (MMD) is a rare and complex cerebrovascular disorder that is diagnosed through imaging studies, such as computed tomography or magnetic resonance imagin, which show progressive narrowing of the terminal portion of the internal carotid arteries and the development of compensatory capillary collaterals. The objective of our study was to identify and clarify the predictive factors for seizures in patients with MMD.

METHODS

From January 2019 to March 2023, a total of 102 patients with MMD were enrolled in this study. Ten patients with seizures after surgery as the main presentation were included. Patients with epilepsy were compared to those without epilepsy in terms of their clinical characteristics. Multivariable analysis was applied to determine factors linked with postoperative seizures.

RESULTS

Ten patients developed seizures after revascularization for MMD. Logistic regression analysis revealed that early seizure (odds ratio [OR], 0.068; 95% CI, 0.014-0.342; P = 0.001), cortical involvement (OR, 9.593; 95% CI, 2.256-40.783; P = 0.002), and postoperative hyperperfusion (OR, 7.417; 95% CI, 1.077-51.093; P = 0.042) were significantly associated with seizures. In a multivariate analysis, it was found that early seizures were significantly associated with a higher likelihood of experiencing seizures (OR, 5.88; 95% CI, 1.01-33.96; P = 0.048), while patients who had seizures were more likely to have cortical involvement (OR, 8.90; 95% CI, 1.55-50.96; P = 0.014) or postoperative hyperperfusion (OR, 12.44; 95% CI, 1.21-127.74; P = 0.034).

CONCLUSIONS

Epilepsy in patients with MMD link with several clinical factors. In patients with MMD who undergo bypass surgery, early seizures, cortical involvement, and postoperative hyperperfusion are significant independent predictive factors for the development of epilepsy.

Technical evolution of pediatric neurosurgery: moyamoya disease

Moyamoya disease (MMD) is a rare steno-occlusive disease of the bilateral internal carotid arteries that predominantly occurs in East Asia. Since the first description of the MMD by Suzuki and Takaku in 1969, significant advances have been made in both basic and clinical understanding of the disease. The incidence and prevalence of pediatric MMD have increased, potentially due to improved detection rates. The advancement of neuroimaging techniques has enabled MRI-based diagnostics and detailed visualization of the vessel wall. Various methods of surgical treatments are successful in pediatric MMD patients, and recent studies emphasize the importance of reducing postoperative complications since the goal of MMD surgery is to prevent future cerebral infarction and hemorrhage. Long-term outcomes following appropriate surgical treatment in pediatric MMD patients have shown promising results, including favorable outcomes in very young patients. Further studies with a large patient cohort are needed to establish individualized risk group stratification for determining the optimal timing of surgical treatment and to conduct multidisciplinary outcome assessments.

Long-Term Surgical Outcome of Indirect Bypass Surgery in Young Children With Moyamoya Disease

BACKGROUND

The prognosis of moyamoya disease (MMD) in young children (younger than 4 years) is worse than that of older adults. The effectiveness of surgery is still inconclusive.

OBJECTIVE

To evaluate long-term outcomes after indirect bypass in young children with MMD.

METHODS

A total of 1417 MMD children underwent indirect bypass from August 1988 to October 2020. This study included 135 patients who were younger than 4 years at the time of surgery. The clinical features and surgical outcomes of these patients were assessed. We analyzed the long-term outcome of 102 children who were followed up for more than 5 years (mean: 18.8 years, range: 5-27.3 years). Cross-sectional analysis was performed to evaluate overall outcomes based on the Lansky Play Performance Scale (LPS). The annual risk of symptomatic stroke after surgery was calculated with a person-year method, and the event-free survival rate was evaluated using the Kaplan-Meier method.

RESULTS

The overall clinical outcome was favorable (LPS ≥ 80) in 88% of the patients. The overall postoperative adverse event rate was 15%, including 1 death. At the last follow-up, 86% of patients who had seizures at diagnosis were seizure-free. During the follow-up, there were 3 symptomatic infarctions on the operated hemisphere (postoperative 3, 3, and 10 months each). There was no hemorrhagic event. The annual infarction rate was 0.16% per person-year. The 20-year event-free survival rates for symptomatic infarction were 97%.

CONCLUSION

Indirect bypass could provide a satisfactory long-term outcome and prevent recurrent stroke in young children with MMD.

Risk factors for early seizure after revascularization in patients with moyamoya disease

BACKGROUND

To investigate the risk factors for early seizure after revascularization in patients with moyamoya disease (MMD).

METHODS

A total of 298 patients with MMD diagnosed in our hospital from 2015 to 2018 were analyzed retrospectively. We summarized the characteristics of seizure after revascularization in patients with MMD and analyzed the predictors of early postoperative seizure.

RESULTS

We identified 15 patients with MMD who developed seizures within 1 week after revascularization. According to logistic regression analysis, age (OR: 1.04, 95% CI 0.998-1.086; P = 0.060) and infarct side (OR: 1.92, 95% CI 0.856-4.290; P = 0.113) were not significantly associated with incident early seizure. Postoperative infarction (OR: 12.89, 95% CI 4.198-39.525; P = 0.000) and preoperative cerebral infarction (OR: 4.08, 95% CI 1.267-13.119; P = 0.018) were confirmed as risk factors for early seizure.

CONCLUSIONS

We believe that a history of preoperative infarction and new infarction are independent risk factors of early seizure in patients with MMD after revascularization.

Seizures, Epilepsy, and Electroencephalography Findings in Pediatric Moyamoya Arteriopathy: A Scoping Review

BACKGROUND

Although seizures are known to occur in children with moyamoya arteriopathy, data regarding characteristics, prevalence, and predictive factors for their development are less established. This study aimed to systematically review literature addressing seizures, epilepsy, and electroencephalography findings in the pediatric moyamoya population.

METHODS

A scoping review was performed by searching PubMed and Ovid:Embase databases for articles that described seizures, epilepsy, and electroencephalography findings in patients aged 0 to 21 years with moyamoya arteriopathy.

RESULTS

The search yielded 43 total articles that addressed the following topics in childhood moyamoya: seizures as the presenting symptom, epilepsy characteristics and management, characteristic electroencephalography findings including rebuildup with discussion of proposed mechanisms, and potential predictive clinical factors for the development of seizures preoperatively and the persistence of epilepsy postoperatively. In the reviewed literature, 9% to 19% of children with moyamoya had epilepsy, with over half of the cases lacking radiographic evidence of ischemia. Young age was the most consistent clinical factor associated with both seizures as the presenting symptom and with moyamoya-related epilepsy. Multiple studies report that seizures, electroencephalographic background abnormalities, and the rebuildup phenomenon improve after successful revascularization surgery.

CONCLUSIONS

This scoping review provides a thorough investigation of the literature available to date on the clinical features of seizures in the pediatric moyamoya population. Literature on this topic is scarce and further studies assessing predictive factors for the development of epilepsy, prognosis as a result of having seizures, and seizure management in this population will help to fill existing knowledge gaps.

Progression in Moyamoya Disease: Clinical Feature, Neuroimaging Evaluation and Treatment

Moyamoya disease (MMD) is a chronic cerebrovascular disease characterized by progressive stenosis of the arteries of the circle of Willis, with the formation of collateral vascular network at the base of the brain. Its clinical manifestations are complicated. Numerous studies have attempted to clarify the clinical features of MMD, including its epidemiology, genetic characteristics, and pathophysiology. With the development of neuroimaging techniques, various neuroimaging modalities with different advantages have deepened the understanding of MMD in terms of structural, functional, spatial, and temporal dimensions. At present, the main treatment for MMD focuses on neurological protection, cerebral blood flow reconstruction, and neurological rehabilitation, such as pharmacological treatment, surgical revascularization, and cognitive rehabilitation. In this review, we discuss recent progress in understanding the clinical features, in the neuroimaging evaluation and treatment of MMD.

The feasibility of performing multiple burr hole surgery in pediatric moyamoya patients as a response to failed mEDAS

OBJECTIVE

To investigate the feasibility and clinical effectiveness of performing multiple burr hole surgery in pediatric moyamoya patients as a response to failed modified encephaloduroarteriosynangiosis (mEDAS).

METHODS

From January 2014 to May 2018, multiple burr hole surgery (MBS) was conducted on 16 hemispheres in 12 patients as a secondary treatment following mEDAS. The male-to-female ratio was 1:2 and the average age at the time of mEDAS was 6 years old. The average patient age was 9 ± 3 years olds (range 7-17) at the time of MBS which occurred an average of 46 months after mEDAS. An average of 10 ± 1 holes (range 8-13) were made. Time-to-peak (TTP) magnetic resonance images (MRI) were taken along 20 axial cuts. Of these cuts, two consecutive cuts on the lateral ventricle were selected to calculate the average value of the region of interest (ROI). The value of the cerebellum was subtracted from the average value of two consecutive cuts. The ROI value was analyzed using a paired t test by SPSS 20 (SPSS Inc., Chicago, IL, USA).

RESULTS

All 16 cases presented improvement of clinical symptoms as determined by ROI analysis of the TTP MRI images. The average ROI value was 5.03 ± 6.36 before MBS and - 15.54 ± 9.42 after MBS. The average change in the ROI value was - 20.58 ± 12.59. The ROI value decreased in all cases after MBS. Magnetic resonance angiography (MRA) also showed a positive effect on vascularization.

CONCLUSION

In pediatric moyamoya patients, MBS is recommended as secondary option as a response to failed mEDAS. Its clinical effectiveness was shown by analyzing TTP images and assisted by MRA and digital subtraction angiography.

Seizure outcome in moyamoya after indirect revascularization in pediatric patients: Retrospective study and literature review

Background:

Moyamoya disease (MMD) is a unique cerebrovascular disorder characterized by progressive stenosis of anterior cerebral circulation. Moyamoya is not an uncommon disease in Saudi Arabia. Although a less common symptom of the disease, the incidence of seizure in MMD ranges from 6 to 30%. Indirect revascularization through Encephaloduroarteriosynangiosis technique is one of the surgical treatment options for MMD. In our cohort, we aim to evaluate seizure outcome in pediatric patients with moyamoya.

Methods:

Eleven patients with seizure as primary presentation for MMD over a period of 10 years were included in the study. All patients underwent EDAS surgery. All patients underwent pre- and postoperative assessment of multiple factors contributing to seizure outcome. Patients were evaluated for surgery control clinically and radiologically.

Results:

About 73% of MMD patients with seizures improved after EDAS surgery (P < 0.0005). Six patients out of 11 became seizure free. Patients with bilateral involvement of disease undergoing bilateral surgery had better seizure control than those undergoing unilateral surgery (P < 0.07).

Conclusion:

Patients with controlled seizure before surgery are more likely to be seizure free after intervention. Seizure outcome is favorable after indirect surgical revascularization in pediatric moyamoya patients.

Postoperative incidence of seizure and cerebral infarction in pediatric patients with epileptic type moyamoya disease: a meta-analysis of single rate

Background

Surgery is a conventional mature treatment for moyamoya disease (MMD). However, whether surgery is also an effective therapy for epileptic type MMD has seldom been investigated systematically. The study aims to summarize the pooled postoperative incidence of seizure and cerebral infarction in pediatric patients with epileptic type moyamoya disease.

Method

The study was a systematic review and critical appraisal with a meta-analysis of cohort studies, both prospective and retrospective. Studies were identified by a computerized search of PubMed, Embase, Web of Science, Wanfang, and CNKI databases. In a literature search, a total of 7 cohort studies were identified. The I²statistic was used to quantify heterogeneity. A fixed-effect model was used to synthesize the results. The linear regression test of funnel plot asymmetry was used to estimate the potential publication bias.

Results

The pooled estimated postoperative incidence of seizure in pediatric patients with epileptic type moyamoya disease was 23.44%. The pooled estimated postoperative incidence of cerebral infarction in pediatric patients with epileptic type moyamoya disease was 9.12%. Low substantial heterogeneity and potential publication bias were present.

Conclusions

Evidence from this study suggests that the postoperative incidence of seizure and cerebral infarction is relatively low. Surgery is an effective and secure therapy for pediatric patients with epileptic type moyamoya disease.

Electroencephalographic features in pediatric patients with moyamoya disease in China

Background

Moyamoya disease (MMD) is a relatively important and common disease, especially in East Asian children. There are few reports about EEG in children with MMD in China till now. This study is aimed to analyze the electroencephalographic features of MMD in pediatric patients in China preliminarily.

Methods

Pediatric patients with MMD who were hospitalized in Peking University International Hospital and Beijing Tiantan Hospital from January 2016 to December 2018 were collected. Clinical and electroencephalography (EEG) findings were analyzed retrospectively.

Results

A total of 110 pediatric patients with MMD were involved, and 17 (15.5%) cases had a history of seizure or epilepsy. Ischemic stroke was associated with a 1.62-fold relative risk of seizure. A subset of 15 patients with complete EEG data was identified. Indications for EEG in patients with MMD included limb shaking, unilateral weakness, or generalized convulsion. Abnormal EEG was seen in 14 (93.3%) cases, with the most common findings being focal slowing 12 (80.0%), followed by epileptiform discharge 10 (66.7%), and diffuse slowing 9 (60.0%). “Re-build up” phenomenon on EEG was observed in one patient.

Conclusions

Seizure and abnormal background activity or epileptiform discharge on EEG were common in pediatric patients with MMD. EEG may play a role in differential diagnosis among the transient neurological events in MMD such as transient ischemic attack and seizure.

Progress in moyamoya disease

Moyamoya disease is characterized by progressive stenosis or occlusion of the intracranial portion of the internal carotid artery and their proximal branches, resulting in ischemic or hemorrhagic stroke with high rate of disability and even death. So far, available treatment strategies are quite limited, and novel intervention method is being explored. This review encapsulates current advances of moyamoya disease on the aspects of epidemiology, etiology, clinical features, imaging diagnosis and treatment. In addition, we also bring forward our conjecture, which needs to be testified by future research.