State of the art of antenatal diagnosis and management of vein of Galen aneurysmal malformations.

Vein of Galen aneurysmal malformation (VGAM) is a severe rare vascular anomaly whose prognosis depends on cerebral and cardiac consequences that can be hard to diagnose, let alone predict in utero. We performed an updated review to summarize current research on the genetics, ultrasound and MRI of VGAM that could help in the diagnosis and management of VGAM. Prenatal diagnosis of VGAM has greatly improved in recent years. Ultrasound allows in utero detection of VGAM in most cases now and is the best exam for prenatal cardiac evaluation. Tricuspid insufficiency is the only cardiac feature associated with poor prognosis. Cardiomegaly may indicate a risk of cardiac failure at birth and should prompt discussion of birth in a specialized facility. Ultrasound can identify constituted cerebral lesions, but MRI diagnoses early signs of cerebral hemodynamic changes, notably through the detection of pseudo-feeders. Genetic exploration should be proposed after VGAM diagnosis. Ultrasound and MRI are essential complementary tools for the diagnosis of VGAM, but also for prognostic evaluation, and provide information for the counseling of parents and optimal management of the pregnancy.

RASA1 phenotype overlaps with hereditary haemorrhagic telangiectasia: two case reports.

Background We report two cases of RASA1-related capillary malformation-arteriovenous malformation (CM-AVM1) syndrome mimicking hereditary haemorrhagic telangiectasia (HHT).Methods and results A 28-year-old man, previously embolised for cerebral arteriovenous malformations (AVMs), presented with epistaxis and typical nasal telangiectasias of HHT. CT scan revealed a large portocaval shunt. The second patient was a 9-year-old girl presenting with cyanosis and several mucocutaneous telangiectasias, similar to those observed in typical cases of HHT. CT scan revealed a huge and complex pulmonary AVM of the right lower lobe and a hepatic AVM within the left lobe. HHT diagnosis was considered possible according to the Curaçao criteria for the two patients, with at least two criteria for each. Genetic tests did not find any mutation in the three classic genes (Endoglin, Activin receptor-like kinase 1 or Mothers against decapentaplegic homolog 4), but identified in both cases an RASA1 mutation, known to cause CM-AVM1 syndrome.Conclusions Pulmonary AVM and portocaval shunt, usually encountered in HHT, have not yet been described in the CM-AVM1 syndrome. RASA1 screening may be considered in case of HHT suspicion, particularly when mutations are not found in the usually affected genes.

Intracranial Aneurysm in Pediatric Population: A Single-Center Experience.

PURPOSE: Pediatric intracranial aneurysms (PIA) are rarer and more complex when compared to adult aneurysms. In general, the clinical presentation of PIA is due to a mass effect, but the presenting symptoms can be also related to ischemia, subarachnoid hemorrhage (SAH), or in a combination of different symptoms. This paper aimed to report a single-center experience with clinical and angiographic aspects of brain aneurysm in children. METHODS: We retrospectively reviewed our prospectively maintained database for patients with intracranial aneurysms in our institution from July 2015 to February 2021. Among these, all patients under 18 years of age submitted to a diagnostic or therapeutic procedure for an intracranial aneurysm were included. RESULTS: Twelve patients were submitted to diagnostic or therapeutic procedures in our department. Three of them had multiple aneurysms, and in total, 17 intracranial aneurysms were assessed in this study. The most frequent location was in the middle cerebral artery (7 cases/41%). Five out of twelve children (42%) presented SAH due to ruptured aneurysm. Three patients (25%) had symptoms due to the mass effect from large aneurysms, with compression of cranial nerves or brainstem. Aneurysms diameters ranged from 1.5 mm to 34 mm (mean 14.2 mm), with six aneurysms being giant and eight being nonsaccular/fusiform. Twelve aneurysms were submitted to endovascular treatment, with one treatment-related clinical complication and later death. CONCLUSION: PIAs are rare diseases that can arise from a variety of different underlying pathological mechanisms. The management of these conditions requires a detailed understanding of the pathology and a multidisciplinary approach. Despite the availability of new technologies, parent vessel occlusion remains a valid option for aneurysms in the pediatric population.

Hyperacute Recanalization Strategies and Childhood Stroke in the Evidence Age.

No controlled pharmacological studies are available in the field of pediatric stroke, except for sickle cell disease. Therefore, while pharmacological and mechanical recanalization treatments have repeatedly shown clinical benefit in adults with arterial ischemic stroke, pediatric strokologists still cannot base their therapeutic management (including hyperacute strategies) on high-level evidence. Once again, pediatricians face the same dichotomic choice: adapting adult procedures now versus waiting-for a long time-for the corresponding pediatric trials. One way out is building a compromise based on observational studies with large, longitudinal, comprehensive, real-life, and multisource dataset. Two recent high-quality observational studies have delivered promising conclusions on recanalization treatments in pediatric arterial ischemic stroke. TIPSTER (Thrombolysis in Pediatric Stroke Extended Results) showed that the risk of severe intracranial hemorrhage after intravenous thrombolysis is low; the Save Childs Study reported encouraging data about pediatric thrombectomy. Beyond the conclusion of a satisfactory global safety profile, a thorough analysis of the methods, populations, results, and therapeutic complications of these studies helps us to refine indications/contraindications and highlights the safeguards we need to rely on when discussing thrombolysis and thrombectomy in children. In conclusion, pediatric strokologists should not refrain from using clot lysis/retrieval tools in selected children with arterial ischemic stroke. But the implementation of hyperacute care is only feasible if the right candidate is identified through the sharing of common adult/pediatric protocols and ward collaboration, formalized well before the child's arrival. These anticipated protocols should never undervalue contraindications from adult guidelines and must involve the necessary pediatric expertise when facing specific causes of stroke, such as focal cerebral arteriopathy of childhood.

Management and Outcomes of Neonatal Arteriovenous Brain Malformations with Cardiac Failure: A 17 Years' Experience in a Tertiary Referral Center.

OBJECTIVES: To assess the management and outcomes of neonatal arteriovenous brain malformations (mostly vein of Galen malformations) complicated by cardiac failure in the era of prenatal diagnosis and endovascular treatment in a tertiary referral center. STUDY DESIGN: This observational study included 77 living newborn infants with arteriovenous brain malformations with cardiac failure, admitted to our referral center from 2001 to 2017. All infants underwent cardiovascular evaluation including echocardiogram and brain magnetic resonance imaging. Long-term survivors had standard neurocognitive assessments. RESULTS: Infants were admitted to the neonatal intensive care unit at a median of 5 days of age (including 18 inborn patients since 2009). Sixty transarterial shunt embolizations were performed in 46 patients during their first month (at a median age of 7.5 days) or postponed beyond the first month in another 10 long-term survivors. Embolization was not performed in 21 infants, including 19 nonsurvivors with severe brain injury, uncontrolled cardiac failure, or multiple organ failure. Cardiac failure requiring vasopressor infusion occurred in 48 patients (64%) during the hospitalization. Infants who survived the first month underwent a median of 3 embolization sessions. Among the 51 survivors, 21 had a good outcome and 19 had a poor outcome at follow-up (median age, 5.3 years); 11 children were lost to follow-up. CONCLUSIONS: In the era of multidisciplinary prenatal diagnosis, using a standardized care protocol, 47% of liveborn infants with an arteriovenous shunt malformation with cardiac failure experienced a favorable outcome.

Long-term outcome of vein of Galen malformation.

AIM: To describe the long-term outcomes of children by the time they reached school age with vein of Galen aneurysmal malformation (VGAM). METHOD: This was a retrospective observational study on a consecutive cohort of patients with VGAM. We included patients with at least one Francophone parent, aged between 6 and 11 years at the time of long-term evaluation. The neurological outcome was assessed with the King's Outcome Scale for Childhood Injury score and eight neurological and behavioural items from the Rivermead Postconcussion Symptoms questionnaire. RESULTS: All 52 patients (17 females, 32 males [data missing for n=3]) with at least one Francophone parent (5 fetuses and 47 children) were included. At the long-term evaluation time-point, 33 patients were alive and 19 patients had died. Risk of postnatal death was associated with severe neonatal cardiac failure (p=0.007) or isosystemic or suprasystemic pulmonary hypertension (p=0.014). Among survivors, 19 had a good outcome with normal schooling and 14 had a poor outcome. Moreover, among the good outcome patients, a large proportion had neurodevelopmental alterations. INTERPRETATION: Long-term outcome of patients with VGAM appears to be less favourable than outcome described at the short- and medium-term, even in the absence of encephalomalacia at birth. Even patients with good outcome often have neuropsychological disorders that may have repercussions on learning and requiring appropriate rehabilitation or medical management. WHAT THIS PAPER ADDS: Long-term outcome appears to be less favourable than described at short- and medium-term follow-up. Even patients with good outcome at these time-points often have minor neuropsychological disorders.

The PHASES score: To treat or not to treat? Retrospective evaluation of the risk of rupture of intracranial aneurysms in patients with aneurysmal subarachnoid hemorrhage.

BACKGROUND AND PURPOSE: The PHASES score was formulated to predict the 5-year risk of rupture for intracranial aneurysms. We retrospectively analyzed all patients treated in our institution for aneurysmal SAH and applied the PHASES score to estimate the probable predicted risk of bleeding in this group of patients. METHODS: Between February 2015 and August 2018, all patients with aneurysmal SAH were retrospectively analyzed and the PHASES score was applied. A total of 155 patients were included with a mean age of 53.8years, including 60 males and 95 females. RESULTS: Of our patients 110 (70.9%) had a PHASES score of below or equal to 5, with a hemorrhagic risk of up to 1.3% over 5years. If we analyze the patients with a risk of below 2% this figure increases to 122 patients (78.7%). Of these 99.3% were European and 0.6% were Japanese (1 patient). In 86 patients (55.4%), the aneurysm was smaller than 5mm and in 10 patients (6.4%) the aneurysm was located in the posterior circulation. CONCLUSION: Of our patients 78.7% had less than a 2% 5-year rupture risk based on their PHASES score, highlighting the discrepancy of the rupture risk calculated with the PHASES score when hypothetically applied to this group of patients. In the hypothetical scenario that our patients had unruptured aneurysms, our retrospective analysis shows that the PHASES score may only provide a weak tool for clinicians to use in the decision-making process as to whether or not to treat these aneurysms.

Loss of function mutations in EPHB4 are responsible for vein of Galen aneurysmal malformation.

See Meschia (doi:10.1093/brain/awy066) for a scientific commentary on this article.Vein of Galen aneurysmal malformation is a congenital anomaly of the cerebral vasculature representing 30% of all paediatric vascular malformations. We conducted whole exome sequencing in 19 unrelated patients presenting this malformation and subsequently screened candidate genes in a cohort of 32 additional patients using either targeted exome or Sanger sequencing. In a cohort of 51 patients, we found five affected individuals with heterozygous mutations in EPHB4 including de novo frameshift (p.His191Alafs*32) or inherited deleterious splice or missense mutations predicted to be pathogenic by in silico tools. Knockdown of ephb4 in zebrafish embryos leads to specific anomalies of dorsal cranial vessels including the dorsal longitudinal vein, which is the orthologue of the median prosencephalic vein and the embryonic precursor of the vein of Galen. This model allowed us to investigate EPHB4 loss-of-function mutations in this disease by the ability to rescue the brain vascular defect in knockdown zebrafish co-injected with wild-type, but not truncated EPHB4, mimicking the p.His191Alafs mutation. Our data showed that in both species, loss of function mutations of EPHB4 result in specific and similar brain vascular development anomalies. Recently, EPHB4 germline mutations have been reported in non-immune hydrops fetalis and in cutaneous capillary malformation-arteriovenous malformation. Here, we show that EPHB4 mutations are also responsible for vein of Galen aneurysmal malformation, indicating that heterozygous germline mutations of EPHB4 result in a large clinical spectrum. The identification of EPHB4 pathogenic mutations in patients presenting capillary malformation or vein of Galen aneurysmal malformation should lead to careful follow-up of pregnancy of carriers for early detection of anomaly of the cerebral vasculature in order to propose optimal neonatal care. Endovascular embolization indeed greatly improved the prognosis of patients.

Thrombectomy or intravenous thrombolysis in patients with NIHSS of 5 or less?

BACKGROUND AND PURPOSE: To compare outcomes of minor stroke patients with intracranial vessel occlusions (IVO) underwent mechanical thrombectomy (MT) versus those treated with intravenous thrombolysis alone (IVT). METHODS: We retrospectively reviewed two large prospective stroke databases from two European centers searching for patients admitted with minor stroke (i.e. NIHSS Score░≤░5), baseline mRS░=░0 and occlusion of the M1-M2 segment of the middle cerebral artery (MCA). Groups receiving (A) IVT alone and (B) MT+/-IVT were compared. Primary outcome measures were MT safety, successful recanalization rate (mTICI 2b-3) and NIHSS shift (discharge NIHSS minus admission NIHSS); secondary outcomes included discharge rates and excellent outcome (mRS 0-1) at 3 months. Univariate and multivariate analyses were performed. RESULTS: Thirty-two patients were enrolled in Group B (19░MT alone; 13 MT░+░IVT) and 24 in Group A. Successful recanalization (mTICI 2b-3) was obtained in 100% of cases in Group B vs 38% in Group A. Symptomatic hemorrhagic transformation rate did not differ between the two groups. Multivariate analysis reported MT as the only predictor of early (<░12░h) favorable NIHSS shift and lower NIHSS at discharge. Moreover, discharge at home and excellent outcome at 3-month follow-up were statistically associated with MT. CONCLUSIONS: MT in patients with minor strokes and intracranial vessel occlusion (IVO) is safe and can determine a rapid improvement of NIHSS Score. MT seems also associated with a higher rate of patients discharged at home after hospitalization and better clinical outcome at 3-month follow-up. Larger randomized trials are warranted to confirm these results.

Clinical and genetic findings in children with central nervous system arteriovenous fistulas.

OBJECTIVE: To assess the spectrum of genetic anomalies in a cohort of children presenting at least one cerebral or spinal pial arteriovenous fistula (AVF), and to describe their clinical characteristics. METHODS: From 1988 to 2016, all consecutive patients with at least one cerebral or spinal pial AVF were screened for genetic disease. All patients aged <18 years were included. Symptoms associated with AVF were recorded: heart failure, neurological deficit/seizure, and hemorrhage. The outcome was assessed using the modified Rankin Scale and school performance in children with cerebral AVF and the American Spinal Injury Association impairment scale in children with spinal AVF. RESULTS: Forty-three children were included. Twenty-five children were male and 18 were female. A germline mutation was identified in 23 probands (53.5 ± 14.9%): 8 in ENG (34.8 ± 14.2%), 1 in ACVRL1 (4.3 ± 6%) leading to a diagnosis of HHT, and 14 in RASA1 (60.9 ± 14.4%) leading to a diagnosis of capillary malformation/arteriovenous malformation type 1. No EphB4 gene mutation was identified. HHT patients presented a significantly lower rate of heart failure at diagnosis (p = 0.047). A trend toward an increased bleeding rate at presentation was observed in HHT (p = 0.069) and an increased rate of giant venous pouch in children in whom no mutation was identified (p = 0.097). Finally, an association with RASA1 mutation was observed in children with associated skin capillary hemangioma (p < 0001). INTERPRETATION: These results highlight the importance of genetic testing in this setting in view of the high frequency of gene mutations in pediatric cerebrospinal AVFs, and show the predominance of RASA1 over HHT mutations. Ann Neurol 2017;82:972-980.

Pseudofeeders on fetal magnetic resonance imaging predict outcome in vein of Galen malformations.

OBJECTIVE: Although vein of Galen aneurysmal malformations (VGAM) can be diagnosed in the fetus, the challenge is predicting the occurrence of its 2 major complications: cardiopulmonary failure and encephalomalacia. This study attempts to determine which fetal brain magnetic resonance imaging (MRI) features might be used to predict the development of these complications at birth. METHODS: The cohort was extracted from a prospectively assembled database of VGAM cases managed at a single referral center from 2000 to 2014. Of 251 patients with VGAM, 83 cases were diagnosed prenatally. A total of 58 patient charts having at least 1 fetal MRI were reviewed. Patterns of brain parenchyma, hydrocephalus, and so-called middle cerebral artery (MCA) "pseudofeeders" were correlated with cardiac failure, pulmonary hypertension, and encephalomalacia at birth. RESULTS: The median gestational age at fetal MRI was 32.3 weeks of pregnancy (±2.3). Nine fetuses (16%) had encephalomalacia. Thirty-one fetuses (53%) had MCA pseudofeeders. Twenty-six fetuses (45%) had prenatal hydrocephalus. Prenatal MCA pseudofeeders were a risk factor for encephalomalacia at birth (p = 0.001). MCA pseudofeeders and hydrocephalus were risk factors for both severe cardiac failure (p = 0.01 and p = 0.04, respectively) and severe pulmonary hypertension (p = 0.014 and p = 0.05, respectively) at birth. INTERPRETATION: MCA pseudofeeders are the result of impaired cerebral blood flow, and are thus a risk factor for further brain melting at birth. Their presence can be used for informing parents and as an aid in management decisions. Ann Neurol 2017;81:278-286.

Regional Pediatric Acute Stroke Protocol: Initial Experience During 3 Years and 13 Recanalization Treatments in Children.

BACKGROUND AND PURPOSE: To evaluate hyperacute management of pediatric arterial ischemic stroke, setting up dedicated management pathways is the first recommended step to prove the feasibility and safety of such treatments. A regional pediatric stroke alert protocol including 2 centers in the Paris-Ile-de-France area, France, was established. METHODS: Consecutive pediatric patients (28 days-18 years) with confirmed arterial ischemic stroke who had acute recanalization treatment (intravenous r-tPA [recombinant tissue-type plasminogen activator], endovascular procedure, or both) according to the regional pediatric stroke alert were retrospectively reviewed during a 40-month period. RESULTS: Thirteen children, aged 3.7 to 16.6 years, had recanalization treatment. Median time from onset to magnetic resonance imaging was 165 minutes (150-300); 9 out of 13 had large-vessel occlusion. Intravenous r-tPA was used in 11 out of 13 patients, with median time from onset to treatment of 240 minutes (178-270). Endovascular procedure was performed in patients time-out for intravenous r-tPA (n=2) or after intravenous r-tPA inefficiency (n=2). No intracranial or peripheral bleeding was reported. One patient died of malignant stroke; outcome was favorable in 11 out of 12 survivors (modified Rankin Scale score 0-2). CONCLUSIONS: Hyperacute recanalization treatment in pediatric stroke, relying on common protocols and adult/pediatric ward collaboration, is feasible. Larger systematic case collection is encouraged.

Patient radiation doses and reference levels in pediatric interventional radiology.

OBJECTIVES: To describe, in a multicentric paediatric population, reference levels (RLs) for three interventional radiological procedures. METHODS: From January 2012 to March 2015, children scheduled for an interventional radiological procedure in two French tertiary centres were retrospectively included and divided into four groups according to age: children younger than 2 years (A1), aged 2-7 years (A5), 8-12 years (A10) and 13-18 years (A15). Three procedures were identified: cerebral digital subtraction angiography (DSA), brain arteriovenous malformation (bAVM) embolization, and head and neck superficial vascular malformation (SVM) percutaneous sclerotherapy. Demographic and dosimetric data, including dose area product (DAP), were collected. RESULTS: 550 procedures were included. For DSA (162 procedures), the proposed RL values in DAP were 4, 18, 12 and 32 Gy∙cm2 in groups A1, A5, A10 and A15, respectively. For bAVM embolization (258 procedures), values were 33, 70, 105 and 88 Gy∙cm2 in groups A1, A5, A10 and A15, respectively. For SVM sclerotherapy (130 procedures), values were 350, 790, 490 and 248 mGy∙cm2 in groups A1, A5, A10 and A15, respectively. CONCLUSION: Consecutive data were available to permit a proposal of reference levels for three major paediatric interventional radiology procedures. KEY POINTS: • We determined reference levels (RLs) for bAVM embolization, DSA and SVM sclerotherapy. • The proposed RLs will permit benchmarking practice with an external standard. • The proposed RLs by age may help to develop paediatric dose guidelines.

Prenatal molecular diagnosis in RASA1-related disease.

RASA1-related disease is a rare autosomal dominant disease characterized by capillary malformations, arteriovenous malformations (AVMs), and/or arteriovenous fistulas (AFVs). Penetrance is nearly complete and vascular malformations may cause serious complications such as organ injury due to oxygenation disorder, brain abscess, hemorrhage, and stroke. Early diagnosis is useful in order to discuss optimal management, including AVMs/AVFs embolization or surgical procedures, and try to prevent some of the complications. In this context, molecular testing of RASA1 gene mutation in relatives may help to better manage the family. All arteriovenous malformations are however not accessible to such procedures. In addition, these therapeutic procedures may result in potential side effects and complications. A couple was referred to our genetics unit and asked us for prenatal genetic testing about a RASA1 mutation. Here, we discuss about arguments that led our team to accept prenatal testing. To the best of our knowledge, no molecular prenatal diagnosis was reported until now in RASA1-related diseases. This first report of prenatal diagnosis in RASA1-related diseases may also offer perspectives for a more general discussion in the field of inherited arteriovenous malformations.

Determinants of cerebral aneurysm occlusion after embolization with the WEB device: a single-institution series of 215 cases with angiographic follow-up.

BACKGROUND: Woven EndoBridge (WEB) devices are becoming a reliable option for the treatment of wide-neck bifurcation aneurysms, but clear predictive factors are still missing to understand the one in five aneurysm remnant rate. OBJECTIVE: To evaluate occlusion outcomes after WEB treatment to identify potential determinants of aneurysm occlusion. METHODS: A single-center database with consecutive aneurysms treated with WEB between July 2012 and October 2021 was reviewed for potential determinants of aneurysm adequate occlusion (defined as a Bicêtre Occlusion Scale Score (BOSS) of 0, 0', 1 or 2), through univariate and multivariable analysis. Patients without angiographic follow-up were excluded. RESULTS: 215 of 247 individual aneurysms were included in the final analysis, of which 59 (27%) were ruptured. Mean age of patients was 56 years (range 23-90 years) and 65% were female. Mean angiographic follow-up was at 18 months (range 3-97 months). Adequate and complete occlusion were achieved in 171/215 (79.5%) and 135/215 (62.8%) of cases, respectively. Aneurysm irregular shape (aOR=0.42, 95% CI 0.20 to 0.88; p=0.02), aneurysm height (aOR=0.79, 95% CI 0.66 to 0.94; p<0.01), and WEB shape modification (aOR=0.98, 95% CI 0.97 to 1.00; p=0.02) were all independent predictors of aneurysm recurrence, whereas the WEB oversizing ratio (WEB width/aneurysm mean width) (aOR=16.4, 95% CI 1.4 to 266.7; p=0.04) was an independent predictor of adequate occlusion. CONCLUSION: In this study we demonstrated that a width oversizing strategy of the WEB device was an independent predictor of aneurysm angiographic occlusion. Conversely, aneurysm height, irregular aneurysm, and WEB shape modification were all independent determinants of angiographic aneurysm remnant. These results may help to select aneurysms suitable for the WEB device and WEB sizing.

Management of aneurysmal recurrence after Woven EndoBridge (WEB) treatment.

BACKGROUND: Around 10% of Woven EndoBridge device (WEB)-treated intracranial aneurysms will need retreatment, and it is generally believed to be more challenging than retreatment after an initial coiling. We aim to report retreatment strategies and outcomes after initial WEB embolizations. METHODS: Databases from four treatment centers, containing consecutive aneurysms treated with a WEB between 2013 and 2022, were reviewed. Demographics, aneurysm characteristics, retreatment strategies and outcomes were collected and analyzed. RESULTS: From a 756 WEB database, 57 aneurysms were included. The global retreatment rate was 7.5% (95% CI 5.6% to 9.4%). The retreatment rate was significantly higher in the ruptured compared with the unruptured population (13% vs 3.9%, respectively, P<0.0001). Aneurysms were retreated on average 21.2 months after the initial WEB treatment (range 4.8-70 months). Surgery was performed in 11% and endovascular treatment in 89% of cases, consisting of flow diversion (48%), stent-assisted coiling (30%), coiling (12%), and second WEB placement (10%). Imaging follow-up was available in 88% of all WEB retreatments (50/57) (average 17 months, 49% digital subtraction angiography), demonstrating complete occlusion in 56% and 'adequate' occlusion in 88%. Morbidity was 5.3% (95% CI 0% to 12.0%) and mortality 0%. No patient experienced rebleeding during the follow-up period. CONCLUSION: The retreatment rate after an initial WEB treatment seems to compare favorably with that of coiling. Endovascular treatment of recurrence following WEB implantation is feasible in most situations; it generally requires the use of a stent and leads to a high rate of satisfactory occlusion.

CLinical Assessment of WEB device in Ruptured aneurYSms (CLARYS): 12-month angiographic results of a multicenter study.

BACKGROUND: The CLinical Assessment of WEB device in Ruptured aneurYSms (CLARYS) study has shown that the endovascular treatment of ruptured bifurcation aneurysms with the Woven EndoBridge (WEB) is safe and effective and provides protection against rebleeding at 1 month and 1 year. The 12-month angiographic follow-up is an important endpoint of the study. METHODS: The CLARYS study is a prospective multicenter study conducted in 13 European centers. The study enrolled 60 patients with 60 ruptured aneurysms of the anterior and posterior circulation. The study was conducted with an independent assessment of safety outcomes and imaging. RESULTS: Sixty patients with 60 ruptured bifurcation aneurysms to be treated with the WEB were included. Fifty-three aneurysms (88.3%) had a broad base with a dome to neck ratio <2 (mean 1.6). Of these, 46 patients were evaluated by an independent core laboratory with follow-up imaging performed at 12 months or before eventual retreatment. At 1 year, 19/46 aneurysms (41.3%) were completely occluded (Raymond-Roy grade I), 21/46 (45.7%) had a residual neck and 6/46 (13.0%) had residual aneurysm filling. Adequate occlusion was reported in 40/46 (87%) aneurysms. Six patients underwent target aneurysm retreatment. CONCLUSIONS: The CLARYS study has previously shown that the use of the WEB in the endovascular treatment of ruptured bifurcation aneurysms provides effective protection against rebleeding with a good safety profile. The angiographic occlusion rates at 1 year reported here are comparable to those already seen in previous multicenter studies which primarily included unruptured aneurysms.

Arteriovenous fistula of the filum terminale: radiological diagnosis and therapeutic management by embolization.

A 60-year-old man had progressive paraparesis, paresthesia of both lower limbs and sphincter dysfunction. He underwent MRI, which revealed perimedullar abnormal vascular channels associated with a hypersignal in the thoracolumbar cord. Because of the patient's age and symptomatology, a dural arteriovenous shunt was first suspected. MRA confirmed dilatation of the perimedullary venous channels, but also revealed an enlarged anterior spinal artery, a finding incompatible with a diagnosis of dural arteriovenous fistula. A lesion, vascularized by the anterior spinal axis and draining secondarily into the perimedullary veins, was thus suspected. Angiography diagnosed a microfistula of the filum terminale; selective distal catheterization of the arterial feeder from T11 to S1 was achieved, and the shunt closed by embolization with acrylic glue. The patient improved after endovascular treatment.

Arteriovenous Cerebral High Flow Shunts in Children: From Genotype to Phenotype.

Objective: To study the genotypes and phenotypes of cerebral arteriovenous fistulas that drain or do not drain through the vein of Galen, and true vein of Galen aneurysmal malformations, in order to determine whether genotyping could help improve classification of these malformations and their management. Methods: We carried out a retrospective review of genetic and phenotypic data in databases of four centers. All children with cerebral arteriovenous fistula or vein of Galen aneurysmal malformations aged below 18 years at onset were included. We recorded the nature of the genetic variant or absence of variant, age at onset, type of malformation, symptoms at onset (hemorrhage, neurological deficit, hydrocephalus, incidental, and heart failure), type of venous drainage and the long-term outcome. Results: One hundred and fifteen children were included. Autosomal dominant variants were identified in 39% of patients. The most frequent variant affected was the RASA1 gene (25%) followed by EPHB4 (8%) and the HHT-associated genes (5%). HHT gene variants were only observed in pial arteriovenous fistula not draining into the vein of Galen; on the contrary, EPHB4 variants were only seen in genuine vein of Galen aneurysmal malformation. RASA1 variants were identified in all types of shunts. Conclusions: EPHB4 variants seem specific to the vein of Galen aneurysmal malformation, RASA1 variants are associated with either pial arteriovenous fistulas or with genuine VGAM and HHT gene variants seem specific to pial arteriovenous fistulas. The genetic data helps to classify these malformations and to guide treatment toward lowest risk of post-operative cerebral ischemic-hemorrhagic complications.

Woven EndoBridge device shape modification can be mitigated with an appropriate oversizing strategy: a VasoCT based study.

BACKGROUND: The Woven EndoBridge (WEB) shape modification (WShM) during follow-up may be a potential cause of poor angiographic outcomes. WShM predisposing factors have not yet been determined. Our systematic use of rotational cone beam computed tomography (VasoCT) imaging during follow-up allowed us to perform the first quantitative analysis of the shape of WEBs over time. Our goal was to identify possible strategies to reduce the occurrence of this phenomenon. METHODS: All patients treated in our hospital with a WEB device between October 2015 and January 2019 were included. Using VasoCT acquisitions, systematically performed after implantation and during follow-up, we analyzed WEB morphology. WShM was defined as the percentage reduction in the distance between the two WEB markers. RESULTS: Sixty-three aneurysms treated with a WEB device were finally included in this analysis. At the last follow-up (mean 15.5 months), mean WShM was 48%±24. The mean WShM was significantly higher in the aneurysm recurrence group than in the adequate occlusion group (51±6.5% vs 36±3.4%, difference 15% points (95% CI 0.7 to 30); p<0.05). Conversely, the extent of WShM did not directly correlate with occlusion rates. Indeed, 32% of completely occluded aneurysms presented severe WShM (≥50%). Importantly, the absence of WShM guaranteed complete occlusion in our study (n=12). We demonstrated that oversizing the width of the WEB significantly correlated with WShM reduction during follow-up (r=-0.38, p=0.002). CONCLUSION: WShM can be partly overcome by use of an appropriate width oversizing strategy that could lead to improved angiographic results.