Characteristics of infarction after encephaloduroarteriosynangiosis in young patients with moyamoya disease

Risk Factors for Preoperative Cerebral Infarction in Infants with Moyamoya Disease

There have been few reports on the risk factors for preoperative cerebral infarction in childhood moyamoya disease (MMD) in infants under 4 years. The aim of this retrospective study is to identify clinical and radiological risk factors for preoperative cerebral infarction in infants under 4 years old with MMD, and the optimal timing for EDAS was also considered. We retrospectively analyzed the risk factors for preoperative cerebral infarction, confirmed by magnetic resonance angiography (MRA), in pediatric patients aged ˂4 years who underwent encephaloduroarteriosynangiosis between April 2005 and July 2022. The clinical and radiological outcomes were determined by two independent reviewers. In addition, potential risk factors for preoperative cerebral infarction, including infarctions at diagnosis and while awaiting surgery, were analyzed using a univariate model and multivariate logistic regression to identify independent predictors of preoperative cerebral infarction. A total of 160 hemispheres from 83 patients aged <4 years with MMD were included in this study. The mean age of all surgical hemispheres at diagnosis was 2.17±0.831 years (range 0.380-3.81 years). In the multivariate logistic regression model, we included all variables with P<0.1 in the univariate analysis. The multivariate logistic regression analysis indicated that preoperative MRA grade (odds ratio [OR], 2.05 [95% confidence interval [CI], 1.3-3.25], P=0. 002), and age at diagnosis (OR, 0.61 [95% CI, 0.4-0.92], P=0. 018) were predictive factors of infarction at diagnosis. The analysis further indicated that the onset of infarction (OR, 0.01 [95% CI, 0-0.08], P<0.001), preoperative MRA grade (OR, 1.7 [95% CI, 1.03-2.8], P=0.037), and duration from diagnosis to surgery (Diag-Op) (OR, 1.25 [95% CI, 1.11-1.41], P<0.001) were predictive factors for infarction while awaiting surgery. Moreover, the regression analysis indicated that family history (OR, 8.88 [95% CI, 0.91-86.83], P=0.06), preoperative MRA grade (OR, 8.72 [95% CI, 3.44-22.07], P<0.001), age at diagnosis (OR, 0.36 [95% CI, 0.14-0.91], P=0.031), and Diag-Op (OR, 1.38 [95% CI, 1.14-1.67], P=0.001) were predictive factors for total infarction. Therefore, during the entire treatment process, careful observation, adequate risk factor management, and optimal operation time are required to prevent preoperative cerebral infarction, particularly in pediatric patients with a family history, higher preoperative MRA grade, duration from diagnosis to operation longer than 3.53 months, and aged ˂3 years at diagnosis.

Clinical Characteristics of Immediate Contralateral Ischemia Subsequent to Revascularization for Moyamoya Disease

BACKGROUND

Moyamoya disease is a bilateral steno-occlusive disease involving the cerebral vasculature. While some patients are affected by procedure-related ipsilateral ischemia, ischemic complications contralateral to the revascularization are rarely observed.

METHODS

We retrospectively investigated 135 hemispheres (103 patients) that underwent revascularization in our institution between April 2006 and September 2022. Revascularization surgery comprised single superficial temporal artery-middle cerebral artery anastomosis and encephalo-myo-synangiosis. Certain patients aged under 10 years underwent indirect revascularization. Bilateral revascularization was performed with an interval of >3 months. Medical records and neuroimages were reviewed, and patients with contralateral ischemic complications were identified. Some cases underwent genetic analysis.

RESULTS

The mean age was 34.5 (range: 5-71) years, and 95 cases (70.4%) were in women. Of the 102 cases examined for the RNF213 c.14429 G > A (p.Arg4810Lys) variant, 33 (32.4%) and 69 (67.6%) showed the GG and GA genotype, respectively. Three cases (2.2%, all female, age range 44-71 years) were complicated with contralateral infarction. The infarcted area distributions of the 2 cases with RNF213 c.14429 G > A variant were patchy and peripheral. The other case showed on magnetic resonance imaging (MRI) angiography total occlusion of the internal carotid artery where patency had been confirmed preoperatively.

CONCLUSIONS

Contralateral ischemia after revascularization occurred in 2.2% of cases. We classified them into peripheral and central types: peripheral type, an infarction owing to hemodynamic insufficiency or intracranial blood flow redistribution; central type, total occlusion of the contralateral internal carotid artery. Intensive preoperative management can minimize the risk of peripheral types, and neurosurgeons should beware of severe central types.

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.

Perioperative Management of Pediatric Patients with Moyamoya Arteriopathy

Pediatric patients with moyamoya arteriopathy are at high risk for developing new onset transient or permanent neurologic deficits secondary to cerebral hypoperfusion, particularly in the perioperative period. It is therefore essential to carefully manage these patients in a multidisciplinary, coordinated effort to reduce the risk of new permanent neurologic deficits. However, little has been published on perioperative management of pediatric patients with moyamoya, particularly in the early postoperative period during intensive care unit admission. Our pediatric neurocritical care team sought to create a multidisciplinary periprocedural evidence- and consensus-based care pathway for high-risk pediatric patients with moyamoya arteriopathy undergoing anesthesia for any reason to decrease the incidence of periprocedural stroke or transient ischemic attack (TIA). We reviewed the literature to identify risk factors associated with perioperative stroke or TIA among patients with moyamoya and to gather data supporting specific perioperative management strategies. A multidisciplinary team from pediatric anesthesia, neurocritical care, nursing, child life, neurosurgery, interventional neuroradiology, neurology, and hematology created a care pathway for children with moyamoya undergoing anesthesia, classifying them as either high or standard risk, and applying an individualized perioperative management plan to high-risk patients. The incidence of neurologic sequelae before and after pathway implementation will be compared in future studies.

Risk Factors for Ischemic Stroke After Revascularization Surgery in Patients with Moyamoya Disease: An Age-Stratified Comparative Meta-Analysis

BACKGROUND

Patients who undergo revascularization surgery for moyamoya disease may develop postoperative ischemic stroke (pIS). Several studies have sought to identify risk factors; however, the findings remain highly inconsistent.

METHODS

PubMed, Scopus, and Web of Science were used to extract references. The first phase of screening required the studies to be in English, involve patients surgically treated for moyamoya disease, and report pIS. The second phase required the studies to provide ≥10 patients and include a control group.

RESULTS

All 22 studies were rated as high quality. Univariate analysis identified pediatrics <3 years of age as a risk factor for pIS (odds ratio [OR], 7.60; P < 0.0001). Among adult patients only, diabetes (OR, 2.10; P = 0.005), a Suzuki grade greater than 3 (OR, 1.74; P = 0.005), mean intraoperative systolic blood pressure (OR, 1.04; P < 0.0001), mean intraoperative diastolic blood pressure (OR, 1.04; P = 0.002), and revascularization in the left hemisphere (OR, 2.09; P = 0.001) were risk factors. Among both age groups, preoperative ischemic stroke (OR, 2.59; P < 0.00001) was a risk factor for pIS. Additionally, perioperative antiplatelet drug administration was a protective factor for specifically acute postoperative white thrombus among adult patients (OR, 0.35; P = 0.002).

CONCLUSIONS

In addition to the methods discussed that can mitigate the risk of pIS, the risk factors identified in our analysis may be of great value among surgeons for identifying high-risk patients in order to apply prophylactic measures, as well as scheduling longer and more frequent follow-up visits.

Risk Factors and Imaging Biomarkers Associated With Perioperative Stroke in Pediatric Moyamoya Arteriopathy

Patients with moyamoya arteriopathy are at high risk for developing ischemic stroke in the perioperative period. We sought to evaluate whether preoperative clinical and neuroimaging biomarkers are associated with postoperative stroke and transient ischemic attack in children with moyamoya following revascularization surgery. We performed a retrospective chart review of pediatric patients who underwent revascularization surgery for moyamoya in the last 15 years. Fifty-three patients who underwent 69 surgeries met the inclusion criteria. We recorded clinical predictors of stroke or transient ischemic attack within 7 days following surgery. We used Suzuki stage and Composite Cerebrovascular Stenosis Score to analyze neuroimaging. Significant risk factors for developing postoperative stroke or transient ischemic attack were younger age at surgery (P = .004) and transient ischemic attack less than 1 month prior to surgery (P < .001). Children under 5 and those with recent preoperative ischemic events should be the focus of investigation to evaluate modifiable risk factors and targeted interventions.

Risk Factors for Cerebral Infarction Early After Revascularization in Children Younger than 5 Years with Moyamoya Disease

OBJECTIVE

Cerebral revascularization is necessary for pediatric patients younger than 5 years with moyamoya disease (MMD). However, they have a high risk of developing cerebral infarction early after surgery. This study aimed to analyze the risk factors for developing cerebral infarction among these patients.

METHODS

The charts of 21 consecutive patients with MMD (39 surgeries) younger than 5 years who had undergone revascularization at our hospital were retrospectively analyzed. Because cerebral infarction occurring within 1 month after surgery was the primary end point, other clinical information was evaluated, including each surgical procedure. Multivariate analysis of the risk factors for postoperative cerebral infarction was performed.

RESULTS

Cerebral infarction occurred after 7 of 39 surgeries (17.9%). Of the 39 surgeries, 23 (59%) included direct and indirect combined revascularization. The incidence of cerebral infarction did not differ significantly between the combined (21.7%) and indirect (12.5%) groups (P = 0.46). Logistic regression showed no association between the revascularization procedure and the occurrence of cerebral infarction after surgery (P = 0.3). However, younger age at surgery was correlated with a higher risk of developing cerebral infarction in the early postoperative period (P = 0.05).

CONCLUSIONS

No differences were found in the risk of developing cerebral infarction early after surgery as a result of surgical procedures. However, younger patients had higher postoperative risk. Further multicenter research should examine this issue for young pediatric patients with moyamoya at high risk of developing cerebral infarction.

Spatially separate cerebral infarction in the posterior cerebral artery territory after combined revascularization of the middle cerebral artery territory in an adult patient with moyamoya disease and fetal-type posterior communicating artery: illustrative case

BACKGROUND

Remote cerebral infarction after combined revascularization of the middle cerebral artery (MCA) territory is rare in patients with moyamoya disease (MMD) with a fetal-type posterior communicating artery (PCoA).

OBSERVATIONS

A 57-year-old woman developed numbness in her right upper limb and transient motor weakness and was diagnosed with MMD. She also had a headache attack and a scintillating scotoma in the right visual field. Preoperative magnetic resonance angiography (MRA) showed stenosis of the left posterior cerebral artery (PCA). Combined revascularization was performed for the left MCA territory. No new neurological deficits were observed for 2 days after the operation, but right hemianopia, alexia, and agraphia appeared on postoperative day (POD) 4. Magnetic resonance imaging showed a new left occipitoparietal lobe infarction, and MRA showed occlusion of the distal left PCA. After that point, the alexia and agraphia gradually improved, but right hemianopia remained at the time of discharge on POD 18.

LESSONS

Cerebral ischemia in the PCA territory may occur after combined revascularization of the MCA territory in patients with fetal-type PCoA. For these cases, a double-barrel bypass or indirect revascularization to induce a slow conversion could be considered on its own as a treatment option.

Paradoxical symptomatic cerebral blood flow decreases after combined revascularization surgery for patients with pediatric moyamoya disease: illustrative case

BACKGROUND

Transient neurological deficits (TNDs) develop after cerebral revascularization in patients with moyamoya disease (MMD). The authors report a rare pediatric MMD case with extensive decreased cerebral blood flow (CBF) and prolonged TNDs after combined revascularization.

OBSERVATIONS

A 9-year-old boy presented with transient left upper limb weakness, and MMD was diagnosed. A right-sided combined surgery was performed. Two years after the surgery, frequent but transient facial (right-sided) and upper limb weakness appeared. The left internal carotid artery terminal stenosis had progressed. Therefore, a left combined revascularization was performed. The patient’s motor aphasia and right upper limb weakness persisted for approximately 10 days after surgery. Magnetic resonance angiography showed that the direct bypass was patent, but extensive decreases in left CBF were observed using single photon emission tomography. With adequate fluid therapy and blood pressure control, the neurological symptoms eventually disappeared, and CBF improved.

LESSONS

The environment of cerebral hemodynamics is heterogeneous after cerebral revascularization for MMD, and the exact mechanism of CBF decreases was not identified. TNDs are significantly associated with the onset of stroke during the early postoperative period. Therefore, appropriate treatment is desired after determining complex cerebral hemodynamics using CBF studies.

Caring for the Child with Spina Bifida

Care for a child with spina bifida can be complex, requiring multiple specialists. Neurosurgical care centers around the initial closure or repair of the spinal defect, followed by management of hydrocephalus, symptoms of the Chiari 2 malformation, and tethered cord. This article reviews definitions and types of spina bifida, considerations surrounding the initial treatment, including fetal surgery, and the ongoing neurosurgical management of common comorbid conditions. The role of interdisciplinary care is stressed, as well as the importance of coordinated transition to adult care at an appropriate age and developmental stage.

Risk factors for postoperative ischemic complications in pediatric moyamoya disease

Background

Ischemic events are the most common postoperative complication in bypass surgery for moyamoya disease (MMD), but the risk factors for pediatric MMD remain unclear. The goal of the study was to investigate the risk factors for postoperative ischemic complications in pediatric MMD patients.

Methods

We retrospectively reviewed a consecutive series of pediatric MMD cases at Beijing Tiantan Hospital, Capital Medical University from June 2010 through June 2019. Preoperative clinical variables and radiographic findings were recorded, and logistic regression analysis was carried out to identify the risk factors for postoperative ischemic events.

Results

A total of 533 operations in 336 patients were included in this study. Postoperative complications occurred after 51 operations (9.6%), including 40/447 indirect bypass procedures, 9/70 direct bypass procedures, and 2/16 combined bypass procedures. Postoperative ischemic events were the most common complication and occurred in 30 patients after 31 procedures (8.9% per patient; 5.8% per operation), including 26/447 indirect bypass procedures, 4/70 direct bypass procedures, and 1/16 combined bypass procedures, and the incidence of these events did not differ significantly between indirect and non-indirect bypass (5.8% vs 5.8%; p = 0.999). Multivariate logistic regression analyses revealed that older age at operation (OR 1.129, 95% CI 1.011–1.260, p = 0.032) and posterior cerebral artery involvement (OR 2.587, 95% CI 1.030–6.496, p = 0.043) were significantly associated with postoperative ischemic events.

Conclusion

We speculate that older age at operation and posterior cerebral artery involvement are risk factors for postoperative ischemic events in pediatric MMD patients.

Monitoring Cerebral Perfusion Changes Using Arterial Spin-Labeling Perfusion MRI after Indirect Revascularization in Children with Moyamoya Disease

OBJECTIVE

To assess the role of arterial spin-labeling (ASL) perfusion MRI in identifying cerebral perfusion changes after indirect revascularization in children with moyamoya disease.

MATERIALS AND METHODS

We included pre- and postoperative perfusion MRI data of 30 children with moyamoya disease (13 boys and 17 girls; mean age ± standard deviation, 6.3 ± 3.0 years) who underwent indirect revascularization between June 2016 and August 2017. Relative cerebral blood flow (rCBF) and qualitative perfusion scores for arterial transit time (ATT) effects were evaluated in the middle cerebral artery (MCA) territory on ASL perfusion MRI. The rCBF and relative time-to-peak (rTTP) values were also measured using dynamic susceptibility contrast (DSC) perfusion MRI. Each perfusion change on ASL and DSC perfusion MRI was analyzed using the paired t test. We analyzed the correlation between perfusion changes on ASL and DSC images using Spearman's correlation coefficient.

RESULTS

The ASL rCBF values improved at both the ganglionic and supraganglionic levels of the MCA territory after surgery (p = 0.040 and p = 0.003, respectively). The ATT perfusion scores also improved at both levels (p < 0.001 and p < 0.001, respectively). The rCBF and rTTP values on DSC MRI showed significant improvement at both levels of the MCA territory of the operated side (all p < 0.05). There was no significant correlation between the improvements in rCBF values on the two perfusion images (r = 0.195, p = 0.303); however, there was a correlation between the change in perfusion scores on ASL and rTTP on DSC MRI (r = 0.701, p < 0.001).

CONCLUSION

Recognizing the effects of ATT on ASL perfusion MRI may help monitor cerebral perfusion changes and complement quantitative rCBF assessment using ASL perfusion MRI in patients with moyamoya disease after indirect revascularization.

Preoperative Risks of Cerebral Infarction in Pediatric Moyamoya Disease

[Figure: see text].

Prevalence of Sleep Disordered Breathing in Children With Myelomeningocele

BACKGROUND

Retrospective studies have shown high rates of sleep disordered breathing in children with myelomeningocele. However, most patients included in those studies underwent polysomnography because of symptoms, so the prevalence of sleep disordered breathing in this population is unknown.

OBJECTIVE

To determine the prevalence of sleep disordered breathing in children with myelomeningocele using screening polysomnography.

METHODS

In this cross-sectional study, all children with myelomeningocele seen in a multi-disciplinary spina bifida clinic between 2016 and 2020 were referred for polysomnography regardless of clinical symptoms. Included children had not previously undergone polysomnography. The primary outcome for this study was presence of sleep disordered breathing, defined as Apnea-Hypopnea Index (AHI, number of apnea or hypopnea events per hour of sleep) greater than 2.5. Clinical and demographic variables relevant to myelomeningocele were also prospectively collected and tested for association with presence of sleep apnea.

RESULTS

A total of 117 participants underwent polysomnography (age 1 mo to 21 yr, 49% male). The majority were white, non-Hispanic. Median AHI was 1.9 (interquartile range 0.6-4.2). A total of 49 children had AHI 2.5 or greater, yielding a sleep disordered breathing prevalence of 42% (95% CI 33%-51%). In multivariable logistic regression analysis, children with more rostral neurological lesion levels had higher odds of sleep disordered breathing (OR for thoracic, mid-lumbar, and low-lumbar: 7.34, 3.70, 4.04, respectively, compared to sacral level, P = .043).

CONCLUSION

Over 40% of a sample of children with myelomeningocele, who underwent screening polysomnography, had significant sleep disordered breathing. Routine screening polysomnography may be indicated in this population.

A rare triad of morning glory disc anomaly, moyamoya vasculopathy, and transsphenoidal cephalocele: pathophysiological considerations and surgical management

Morning glory disc anomaly is a congenital abnormality of the optic disc and peripapillary retina reported as an isolated condition or associated with various anomalies, including basal encephaloceles and moyamoya vasculopathy. However, the co-occurrence of these three entities is extremely rare and the pathogenesis is still poorly understood. Moreover, data on the surgical management and long-term follow-up of the intracranial anomalies are scarce. Here, we describe the case of a 11-year-old boy with morning glory disc anomaly, transsphenoidal cephalocele, and moyamoya vasculopathy, who underwent bilateral indirect revascularization with encephalo-duro-myo-arterio-pericranio-synangiosis at the age of 2 years, and endoscopic repair of the transsphenoidal cephalocele at the age of 6 years. A rare missense variant (c.1081T>C,p.Tyr361His) was found in OFD1, a gene responsible for a X-linked ciliopathy, the oral-facial-digital syndrome type 1 (OFD1; OMIM 311200). This case expands the complex phenotype of OFD1 syndrome and suggests a possible involvement of OFD1 gene and Shh pathway in the pathogenesis of these anomalies.

Postoperative stroke and neurological outcomes in the early phase after revascularization surgeries for moyamoya disease: an age-stratified comparative analysis

Stroke and neurological outcomes in the early phase following revascularization for moyamoya disease (MMD) may depend on the patient's age. In this study, an age-stratified comparative analysis was performed to clarify this issue. We reviewed 105 MMD patients who underwent 179 revascularization surgeries. The demographic characteristics were collected in four age groups (≤ 5 and 6-17 years for pediatric patients and 18-49 and ≥ 50 years for adults). Additionally, we assessed the incidence of subsequent stroke and deterioration of modified Rankin Scale (mRS) score. Then, we evaluated predictors of postoperative stroke and mRS deterioration using logistic regression. The mean patient age was 26.2 ± 18.5 years. No significant difference in the incidence of postoperative stroke was observed between age groups; however, the incidence tended to be increased among patients aged ≤ 5 years (17.9%) and patients aged ≥ 50 years (16.7%). Deterioration of mRS scores was significantly associated with ages ≤ 5 years (17.9%) and ≥ 50 years (11.1%). Logistic regression showed that posterior cerebral artery involvement (odds ratio [OR], 4.6) and postoperative transient neurological events (TNEs) (OR, 5.93) were risk factors for postoperative stroke. Age ≤ 5 years (OR, 9.73), postoperative TNEs (OR, 7.38), and postoperative stroke (OR, 49) were identified as predictors of unfavorable neurological outcomes. The novel feature of this comparative analysis by age group is that membership in the early-childhood MMD patient group (under 5 years old) was an independent risk factor for unfavorable short-term neurological outcomes and was mainly associated with the incidence of postoperative severe cerebral infarction.

Limits and pitfalls of indirect revascularization in moyamoya disease and syndrome

Moyamoya vasculopathy is a rare chronic cerebrovascular disorder characterized by the stenosis of the terminal branches of the internal carotid arteries and the proximal tracts of anterior and middle cerebral arteries. Although surgical revascularization does not significantly change the underlying pathogenic mechanisms, it plays a pivotal role in the management of affected individuals, allowing to decrease the risk of ischemic and hemorrhagic complications. Surgical approaches may be direct (extracranial-intracranial bypass), indirect, or a combination of the two. Several indirect techniques classifiable according to the tissue (muscle, periosteum, galea, dura mater, and extracranial tissues) or vessel (artery) used as a source of blood supply are currently available. In this study, we reviewed the pertinent literature and analyzed the advantages, disadvantages, and pitfalls of the most relevant indirect revascularization techniques. We discussed the technical aspects and the therapeutical implications of each procedure, providing a current state-of-the-art overview on the limits and pitfalls of indirect revascularization in the treatment of moyamoya vasculopathy.

Surgical outcomes for pediatric moyamoya: a systematic review and meta-analysis

OBJECTIVE

The optimal revascularization for pediatric moyamoya for reducing the incidence of future stroke events remains to be determined.

METHODS

The authors conducted a search of PubMed, MEDLINE, Embase, and Web of Science electronic databases from inception until January 2019. The primary endpoint was the presence of a future ischemic stroke event. Secondary endpoints were angiographic outcomes as measured by postoperative Matsushima grade and clinical symptom persistence. Patients who underwent either direct or combined direct/indirect revascularization were classified into the direct cohort. Data from each study on presence of postoperative stroke events were used to generate standardized mean differences and 95% confidence intervals, which were combined using inverse variance-weighted averages of standardized mean differences in a random effects model.

RESULTS

Twenty-nine studies met the inclusion criteria for analysis, comprising 2258 patients (1011 males, mean age 8.3 ± 1.8 years) who were followed up clinically for an average of 71.4 ± 51.3 months. One hundred fifty-four patients underwent direct bypass alone, 680 patients underwent either direct or combined direct/indirect revascularization procedures, while 1424 patients underwent indirect bypass alone. The frequencies of future stroke events in patients undergoing direct bypass alone, combined bypass, or indirect bypass alone were 1 per 190.3 patient-years, 1 per 108.9 patient-years, and 1 per 61.1 patient-years, respectively, in each cohort. The estimated stroke rates were 9.0% with indirect revascularization, 4.5% with direct revascularization alone, and 6.0% with combined revascularization. A forest plot did not reveal any significant differences in the incidence of future stroke events or angiographic outcomes following direct-only, combined, or indirect-only revascularization.

CONCLUSIONS

Direct, indirect, and combined indirect/direct bypass techniques are all effective revascularization options for pediatric moyamoya disease. A relative paucity of granular studies-and inherent surgical selection bias-limits direct comparison between interventions. Suitably designed prospective cohort studies may be useful in identifying patients likely to receive benefit from specific procedures.

Evaluation and treatment of children with radiation-induced cerebral vasculopathy

OBJECTIVE

Stenoocclusive cerebral vasculopathy is an infrequent delayed complication of ionizing radiation. It has been well described with photon-based radiation therapy but less so following proton-beam radiotherapy. The authors report their recent institutional experience in evaluating and treating children with radiation-induced cerebral vasculopathy.

METHODS

Eligible patients were age 21 years or younger who had a history of cranial radiation and subsequently developed vascular narrowing detected by MR arteriography that was significant enough to warrant cerebral angiography, with or without ischemic symptoms. The study period was January 2011 to March 2019.

RESULTS

Thirty-one patients met the study inclusion criteria. Their median age was 12 years, and 18 (58%) were male. Proton-beam radiation therapy was used in 20 patients (64.5%) and photon-based radiation therapy was used in 11 patients (35.5%). Patients were most commonly referred for workup as a result of incidental findings on surveillance tumor imaging (n = 23; 74.2%). Proton-beam patients had a shorter median time from radiotherapy to catheter angiography (24.1 months [IQR 16.8-35.4 months]) than patients who underwent photon-based radiation therapy (48.2 months [IQR 26.6-61.1 months]; p = 0.04). Eighteen hemispheres were revascularized in 15 patients. One surgical patient suffered a contralateral hemispheric infarct 2 weeks after revascularization; no child treated medically (aspirin) has had a stroke to date. The median follow-up duration was 29.2 months (IQR 21.8-54.0 months) from the date of the first catheter angiogram to last clinic visit.

CONCLUSIONS

All children who receive cranial radiation therapy from any source, particularly if the parasellar region was involved and the child was young at the time of treatment, require close surveillance for the development of vasculopathy. A structured and detailed evaluation is necessary to determine optimal treatment.

Contralateral acute vascular occlusion following revascularization surgery for moyamoya disease

OBJECTIVE

Revascularization surgery is a safe and effective surgical treatment for symptomatic moyamoya disease (MMD) and has been shown to reduce the frequency of future ischemic events and improve quality of life in affected patients. The authors sought to investigate the occurrence of acute perioperative occlusion of the contralateral internal carotid artery (ICA) with contralateral stroke following revascularization surgery, a rare complication that has not been previously reported.

METHODS

This study is a retrospective review of a prospective database of a single surgeon's series of revascularization operations in patients with MMD. From 1991 to 2016, 1446 bypasses were performed in 905 patients, 89.6% of which involved direct anastomosis of the superficial temporal artery (STA) to a distal branch of the middle cerebral artery (MCA). Demographic, surgical, and radiographic data were collected prospectively in all treated patients.

RESULTS

Symptomatic contralateral hemispheric infarcts occurred during the postoperative period in 34 cases (2.4%). Digital subtraction angiography (DSA) was performed in each of these patients. In 8 cases (0.6%), DSA during the immediate postoperative period revealed associated new occlusion of the contralateral ICA. In each of these cases, revascularization surgery involved direct anastomosis of the STA to an M4 branch of the MCA. Preoperative DSA revealed moderate (n = 1) or severe (n = 3) stenosis or occlusion (n = 4) of the ipsilateral ICA and mild (n = 2), moderate (n = 4), or severe (n = 2) stenosis of the contralateral ICA. The baseline Suzuki stage was 4 (n = 7) or 5 (n = 1). The collateral supply originated exclusively from the intracranial circulation in 4/8 patients (50%), and from both the intracranial and extracranial circulation in the remaining 50% of patients. Seven (88%) of 8 patients improved symptomatically during the acute postoperative period with induced hypertension. The modified Rankin Scale (mRS) score at discharge was worse than baseline in 7/8 patients (88%), whereas 1 patient had only minor deficits that did not affect the mRS score. At the 3-year follow-up, 3/8 patients (38%) were at their baseline mRS score or better, 1 patient had significant disability compared with preoperatively, 2 patients had died, and 1 patient was lost to follow-up. Three-year follow-up is not yet available in 1 patient.

CONCLUSIONS

Acute occlusion of the ICA on the contralateral side from an STA-MCA bypass is a rare, but potentially serious, complication of revascularization surgery for MMD. It highlights the importance of the hemodynamic interrelationships that exist between the two hemispheres, a concept that has been previously underappreciated. Induced hypertension during the acute period may provide adequate cerebral blood flow via developing collateral vessels, and good outcomes may be achieved with aggressive supportive management and expedited contralateral revascularization.

Evaluation of frequency-selective non-linear blending technique on brain CT in postoperative children with Moyamoya disease

OBJECTIVE

To evaluate whether a frequency-selective non-linear blending (BC) technique can improve tissue contrast and infarct detection on non-enhanced brain CT (NECT) in postoperative Moyamoya (MMD) patients.

MATERIALS AND METHODS

From January 2010 to December 2017, 33 children (13boys and 20girls; mean age 9.1±3.4 years) with MMD postoperatively underwent NECT followed by diffusion MRI. We compared the contrast-to-noise ratio (CNR) between gray matter (GM) and white matter (WM) in NECT and BC images and the CNR between the infarct lesion and adjacent normal-appearing brain in NECT and BC images using a paired t-test. We assessed image noise, GM-WM differentiation, artifacts, and overall quality using a Wilcoxon signed rank test. A McNemar two-tailed test was conducted to compare the diagnostic accuracy of infarct detection.

RESULTS

The CNR between GM and WM and the CNR of the infarct was better in BC images than in NECT images (3.9±1.0 vs. 1.8±0.6, P<0.001 and 3.6±0.3 vs. 1.9±0.2, P<0.001), with no difference in overall image quality observed. The sensitivity and specificity of infarct detection were 55.0% and 76.9% using NECT, and 70.0% and 69.2% using BC technique. The diagnostic accuracy of NECT and BC technique was 63.6% (21/33) and 69.7% (23/33), respectively.

CONCLUSION

This study showed that the BC technique improved CNR and maintained image quality. This technique may also be used to identify ischemic brain changes in postoperative MMD patients by improving the CNR of the infarct lesion.

Risk factors for postoperative stroke in adults patients with moyamoya disease: a systematic review with meta-analysis

Background

This systematic review and meta-analysis aimed to clarify the risk factors for postoperative stroke in adult patients with moyamoya disease (MMD).

Methods

We comprehensively searched MEDLINE/PubMed, Web of Science, and Cochrane Library for eligible published literature with regard to the risk factors and postoperative complications in adult patients with MMD. Statistical analysis was conducted using Stata version 12.0. Pooled odds ratio (OR) with 95% confidence interval (CI) were assessed for each risk factor.

Results

There were 8 studies encompassing 1649 patients who underwent surgery with MMD were selected for analysis. Preoperative ischemic event significantly increase the risk of postoperative stroke events (OR = 1.40; 95%CI = 1.02–1.92; P = 0.039). PCA involvement correlate with an increased risk of post-infarction (OR = 4.60; 95%CI = 2.61–8.11; P = 0.000). Compared to direct bypass, patients who underwent indirect bypass or combined bypass could significantly increase the risk of postoperative stroke events. (OR = 1.17; 95%CI = 1.03–1.33; p = 0.017). MMD patients with diabetes were associated with an increased risk of postoperative stroke events (OR = 4.02, 95% CI = 1.59–10.16; p = 0.003). MMD patients with hypertension, age at onset and male sex were not associated with an increased risk of postoperative stroke events (P > 0.05).

Conclusions

This systematic review and meta-analysis indicated that preoperative ischemic events, PCA involvement and diabetes were independent risk factors for postoperative stroke in MMD patients. Therefore, in order to ensure the curative effect of patients with MMD, it is very necessary to detect these risk factors and prevent postoperative complications in time.

Enlarged Encephalo-Duro-Myo-Synangiosis Treatment for Moyamoya Disease in Young Children

OBJECTIVE

To retrospectively evaluate the midterm therapeutic effect of enlarged encephalo-duro-myo-synangiosis (EDMS) for moyamoya disease (MMD) in young children.

METHODS

Seventy-seven children diagnosed with MMD by digital subtraction angiography (DSA) or magnetic resonance angiography (MRA) were treated between January 2011 and December 2014 in our center. Their clinical features, imaging, and operative reports were analyzed.

RESULTS

Four patients presented with intracerebral hemorrhage, whereas 73 presented with ischemic symptoms. Revascularization procedures were performed unilaterally on 11 left hemispheres and 9 right hemispheres, and 57 had bilateral surgeries. The average length of surgery was 143 ± 24 minutes, with 28 ± 9 mL of blood loss. The mean period of follow-up was 28.43 ± 15.31 months. Cerebral blood flow increased 3 months after the operations in the previously affected regions. Collateralization from the deep temporal artery, superficial temporal artery, and the middle meningeal artery was found by DSA or MRA. In cases where single-photon emission computed tomography was obtained, it demonstrated better perfusion postoperatively. The ischemic symptoms were relieved in 118 (88.06%) hemispheres, and remained stable in 5 (3.73%) hemispheres. There were 12 radiographic cerebral infarctions (8.96%) within 1 month postoperatively.

CONCLUSIONS

Enlarged EDMS is safe and effective for MMD in young children. Extensive and multilayered revascularization could significantly preserve neurologic function. The long-term effect on posterior circulation disease development needs further investigation.