Aneurysms of the vein of Galen: embryonic considerations and anatomical features relating to the pathogenesis of the malformation

Multidisciplinary care of fetal vein of Galen arteriovenous malformation diagnosed via Doppler ultrasound and magnetic resonance imaging: A case report

Fetal vein of Galen malformation (VOGM) represents a rare congenital anomaly affecting the fetal cerebral vasculature. A 27-year-old Middle Eastern woman was referred due to intrauterine growth restriction (IUGR) and fetal cardiac anomalies identified at 35 weeks of gestation. The diagnosis of fetal VOGM with dilated neck vessels was established through a combination of color Doppler ultrasonography and magnetic resonance imaging. A multidisciplinary approach involving maternal-fetal medicine, neonatology, pediatric cardiology, and interventional radiology was implemented. Given the grave prognosis for the baby, the patient received comprehensive counseling. Subsequent monitoring revealed a non-reassuring fetal heart trace, prompting the decision to perform a cesarean section. The newborn, a girl, was admitted to the neonatal intensive care unit for further management but she died shortly thereafter, with heart failure and intracranial hemorrhage identified as the probable causes of death. In summary, the diagnosis and management of VOGMs demand specialized expertise and a collaborative, multidisciplinary approach to optimize patient care and outcomes.

Vein of Galen aneurysmal malformation: does size affect outcome?

PURPOSE

To validate a semiautomated method for segmenting vein of Galen aneurysmal malformations (VGAM) and to assess the relationship between VGAM volume and other angioarchitectural features, cardiological findings, and outcomes.

METHODS

In this retrospective study, we selected all subjects with VGAM admitted to the Gaslini Children's Hospital between 2009 and 2022. Clinical data were retrieved from electronic charts. We compared 3D-Slicer segmented VGAM volumes obtained by two independent observers using phase-contrast MR venography to those obtained with manual measurements performed on T2-weighted images. The relationship between VGAM volumes and clinical and neuroimaging features was then explored.

RESULTS

Forty-three subjects with VGAM (22 males, mean age 6.56 days) were included in the study. Manual and semiautomated VGAM volumes were well correlated for both readers (r = 0.86 and 0.82, respectively). Regarding reproducibility, the inter-rater interclass correlation coefficients were 0.885 for the manual method and 0.992 for the semiautomated method (p < 0.001). The standard error for repeated measures was lower for the semiautomated method (0.04 versus 0.40 of manual method). Higher VGAM volume was associated with superior sagittal sinus narrowing, jugular bulb stenosis, and aqueductal stenosis (p < 0.05). A weak correlation was found between VGAM volume and straight sinus dilatation (r = 0.331) and superior sagittal sinus index (r =  - 0.325). No significant associations were found with cardiac findings, post-embolization complications, and outcome (p > 0.05).

CONCLUSIONS

Semiautomated VGAM volumetry is feasible and reliable with improved reproducibility compared to the manual method. VGAM volume is not a prognostic factor for clinical outcome, but it is related to other venous findings with potential hemodynamic effects.

Literature review and case report: Rare case of successful prenatal detection of Vein of Galen Malformation (VGAM)

Vein of Galen aneurysmal malformation (VGAM) is a rare vascular anomaly originating during embryonic development, specifically between the 6th and 11th weeks of gestation. This malformation results from abnormal arteriovenous connections between primitive choroidal arteries and the median prosencephalic vein (MPV) of Markowski. Typically, the MPV regresses by the 11th week, but in VGAM, this regression is hindered, leading to persistent abnormal flow and the formation of arteriovenous shunts. We present a case of successful prenatal detection, as well as a comprehensive literature review that summarizes current knowledge, emphasizes the importance of prenatal detection, detailed imaging techniques, understanding clinical presentations, and outlines treatment options. Prenatal detection, crucial for early intervention, has become feasible through ultrasonography and MRI. Fetal MRI has emerged as the gold standard, offering detailed insights into arterial feeders, nidus presence, fistula position, venous drainage, and potential complications. The clinical presentation of VGAM varies with age, and neonates diagnosed in utero may exhibit signs of high-output cardiac failure. Early detection is critical for timely intervention, as untreated VGAMs often result in high mortality rates. Prognosis depends on the severity of heart failure, the number of arteriovenous shunts, and the presence of accompanying fetal abnormalities. Various imaging modalities, including CT angiography and digital subtraction angiography (DSA), aid in the assessment and treatment of VGAM. DSA remains the gold standard for evaluating angioarchitecture and guiding endovascular interventions. The optimal treatment for VGAM is transarterial embolization, offering significant improvements in prognosis. Surgical interventions are limited due to high morbidity and mortality. Management decisions should consider the balance between minimizing neurological damage and achieving maximum embolization effectiveness.

Update on the Vein of Galen Aneurysmal Malformation : Disease Concept and Genetics

Vein of Galen aneurysmal malformation is one of important pediatric arteriovenous shunt diseases, especially among neonates and infants. Here, early history of the disease identification, basic pathoanatomy with a focus on the embryonic median prosencephalic vein, classification and differential diagnoses, and recent genetic studies are reviewed.

Spontaneous thrombosis of type II vein of Galen aneurysmal malformation: a case report

Vein of Galen malformations (VGAMs) are rare and complex congenital brain vascular anomalies that pose significant diagnostic and treatment challenges. The natural history of this type of vascular anomaly is very poor, with many patients succumbing to complications such as congestive heart failure, hydrocephalus, and brain parenchymal injury. Although the clinical course of most VGAMs was considered unfortunate, with meticulous imaging, a group of lesions with a more placid presentation and course can be identified.

Vein of Galen Aneurysmal Malformation: A Case Report

Vein of Galen aneurysmal malformation is a relatively rare disease in which failure of the median prosencephalic vein of Markowski to involute early in gestation leads to a grossly dilated deep cerebral vein with multiple arterial feeders, causing a large arteriovenous shunt which leads to high-output cardiac failure. We describe a case of a term neonate who presented to a tertiary neonatal centre on day one of life with history, symptoms, and signs consistent with perinatal asphyxia; however, in the context of worsening multi-organ dysfunction and cardiomegaly, the infant was found to have a severe vein of Galen aneurysmal dilatation leading to high-output cardiac failure. The patient was transferred to a tertiary paediatric hospital and underwent a total of four coiling procedures to embolise the multiple feeder arteries supplying the aneurysmal malformation. This case highlights the difficulties in diagnosing this relatively uncommon condition, particularly in the context of a possible perinatal insult.

Mutation of key signaling regulators of cerebrovascular development in vein of Galen malformations

To elucidate the pathogenesis of vein of Galen malformations (VOGMs), the most common and most severe of congenital brain arteriovenous malformations, we performed an integrated analysis of 310 VOGM proband-family exomes and 336,326 human cerebrovasculature single-cell transcriptomes. We found the Ras suppressor p120 RasGAP (RASA1) harbored a genome-wide significant burden of loss-of-function de novo variants (2042.5-fold, p = 4.79 x 10-7). Rare, damaging transmitted variants were enriched in Ephrin receptor-B4 (EPHB4) (17.5-fold, p = 1.22 x 10-5), which cooperates with p120 RasGAP to regulate vascular development. Additional probands had damaging variants in ACVRL1, NOTCH1, ITGB1, and PTPN11. ACVRL1 variants were also identified in a multi-generational VOGM pedigree. Integrative genomic analysis defined developing endothelial cells as a likely spatio-temporal locus of VOGM pathophysiology. Mice expressing a VOGM-specific EPHB4 kinase-domain missense variant (Phe867Leu) exhibited disrupted developmental angiogenesis and impaired hierarchical development of arterial-capillary-venous networks, but only in the presence of a "second-hit" allele. These results illuminate human arterio-venous development and VOGM pathobiology and have implications for patients and their families.

Aortic Steal Correlates with Acute Organ Dysfunction and Short-Term Outcomes in Neonates with Vein of Galen Malformation

INTRODUCTION

Vein of Galen aneurysmal malformation (VGAM) is a rare, congenital cerebrovascular malformation with high morbidity and mortality. Parameters to foresee clinical progression and allow individualized parent counseling are lacking. The aim of this study was to evaluate aortic steal measured by Doppler ultrasound as a prognostic parameter in these neonates.

METHODS

A retrospective monocentric analysis of cardiac ultrasound exams before embolization in neonates with VGAM was conducted. Percentage of aortic steal measured by time-averaged maximum velocity above and below the zero flow baseline by pulsed Doppler ultrasound at the preductal aortic isthmus was calculated. Association of aortic steal with parameters of acute organ dysfunction (Bicêtre neonatal evaluation score [BNES], neonatal multiple organ dysfunction score [NeoMODS]) and mortality and determination of correlation between aortic steal and cerebral damage on initial and follow-up cerebral magnetic resonance imaging (cMRI) were evaluated.

RESULTS

Twelve neonates were included, of which 3 died. Per 10 percentage point increase of aortic steal, BNES decreased by 1.64 (95% confidence interval [CI]: 1.28-2.0) points and the maximum observed NeoMODS increased by 1.25 (CI: 0.94-1.57) points. The odds for mortality increased by 2.3 (CI: 1.14-13.67) per 10 percentage point increase of aortic steal. There was a correlation between aortic steal and cerebral damage at baseline (white matter ρ [rho] = 0.34, gray matter ρ = 0.81) and follow-up (white matter ρ = 0.80, gray matter ρ = 0.72).

CONCLUSION

The degree of aortic steal in neonates with VGAM was highly associated with the severity of organ dysfunction, disease progression on cMRI, and mortality.

A Curious Case of Proptosis and Intracranial Calcifications Caused by a Vein of Galen Aneurysmal Malformation

Vein of Galen aneurysmal malformation (VGAM) is a rare, congenital, intracerebral arteriovenous malformation with a poor prognosis. This disorder commonly presents during the neonatal period and rarely in infancy and childhood. Reported here is a case of VGAM in a three-month-old female baby who presented with proptosis and intracranial calcifications, which are rare presentations of this rare entity. The diagnosis was confirmed by magnetic resonance imaging (MRI).

Spontaneous thrombosis of vein of Galen malformation managed with surgical resection: a case‑based review

INTRODUCTION

Vein of Galen malformation (VOGM) is an exceptionally uncommon form of congenital intracranial vascular malformations. It is highly unusual for this lesion to spontaneously thrombose. The clinical presentation of a patient may range from being asymptomatic to critically ill. The underlying pathophysiological mechanisms that cause spontaneous thrombosis are still poorly understood.

METHODS AND RESULTS

The literature on spontaneous thrombosis of VOGM was systematically reviewed, analyzed, and summarized with a focus on its pathophysiology, types, clinical presentations, diagnosis, management, and outcomes. It was also illustrated with a case presentation. The case presents an unusual presentation and location of a VOGM in a 2-year-old boy who was successfully treated with surgical resection.

CONCLUSIONS

A handful of cases of thrombosed VOGM have been reported worldwide where surgery was used to treat the condition. Low-flow fistulas of the mural type are prone to spontaneous thrombosis, have delayed clinical presentations, and are typically diagnosed in young children. Among the many possible manifestations, hydrocephalus is by far the most common. In the absence of blood flow, MRI is the diagnostic test of choice. Depending on the patient's symptoms, surgery to either remove the aneurysm or divert the cerebrospinal fluid usually results in a good prognosis.

Long-Term Outcomes of Endovascular Embolization in a Vein of Galen Aneurysmal Malformation: A Single-Center Experience

BACKGROUND

A vein of Galen aneurysmal malformation (VGAM) is a rare congenital cerebral vascular condition with a high mortality rate if left untreated. This study describes the long-term outcomes of patients with VGAM, who were treated with endovascular embolization.

METHODS

This retrospective analysis focused on VGAM patients who underwent one or more endovascular embolization sessions between January 2008 and December 2022. The study included newborns and children under 18 years. Data encompassed clinical and demographic characteristics, types of endovascular embolization, treatment complications, mortality rates, and long-term outcomes.

RESULTS

Out of 22 VGAM cases, the majority were boys (86.36%), and the average age of the participants was 38 months, ranging from 25 days to 17 years. Endovascular embolization using liquid embolizing agents was the most common intervention (50%), and around 73% of patients underwent multiple sessions. Some patients underwent ventriculoperitoneal shunting (VPS) due to persistent hydrocephalus. In long-term outcomes, four patients (18.2%) showed developmental delays, and 16 patients (72.7%) had a positive outcome.

CONCLUSIONS

Combining endovascular therapy with a comprehensive management strategy significantly reduces mortality rates and improves the possibility of normal neurological development in patients.

Vein of Galen aneurysmal malformation in newborns: a retrospective study to describe a paradigm of treatment and identify risk factors of adverse outcome in a referral center

Background

Vein of Galen aneurysmal malformation (VGAM) is a rare cerebral vascular malformation associated with significant morbidity and mortality. Newborns with VGAM without adequate treatment may develop rapidly deteriorating high output heart failure (HOHF) and are at risk for severe neurological outcomes.

Objective

To describe the clinical course and management of newborns with VGAM, and identify which echocardiographic and neuroradiologic factors may be associated with severe heart failure at birth and adverse short term outcomes.

Methods

This is a single center retrospective cohort study including all consecutive newborns with VGAM admitted to Gaslini Children's Hospital between 2009 and 2022. We reviewed clinical data, intensive care support, fetal and neonatal cardiologic and neuroradiologic findings and we studied the association with severe HOHF, endovascular complications and death.

Results

Out of 40 newborns, 17 (42.5%) developed severe HOHF requiring early endovascular procedures. Medical treatment was focused on the main components of HOHF by providing inotropic support and peripheral vasodilation. Pulmonary vasodilators were avoided to reduce the negative effects of pulmonary overflow and prevent vascular remodeling. Reduction of the obligatory left to right shunt through the VGAM was possible only through endovascular treatment. Fetal cardiothoracic ratio was significantly associated with severe HOHF at birth and death. Cardiologic parameters of right ventricular overload, pulmonary hypertension and systemic steal were the leading findings associated with haemodynamic compromise at birth. The mediolateral diameter of the straight or falcine sinus at its shortest section (SS-MD), and arterial pseudofeeders were significantly associated with severe HOHF at birth in prenatal and postnatal assessments. None of the postnatal echocardiographic and MRI variables, nor a higher inotropic support were associated with major periprocedural complications or death. Mortality was due to palliation for congenital severe brain damage (4/40, 10%), or major periprocedural complications (3/40, 7.5%). None of the patients died due to HOHF and multiorgan failure. Overall survival at discharge was 82.5% (33/40).

Conclusions

The complexity of neonatal VGAM pathophysiology requires a multidisciplinary approach, specialized intensive care management, and early endovascular treatment to reduce mortality and optimize clinical outcomes. Cardiologic and neuroradiologic parameters are key to define risk stratification and treatment strategies.

Intracranial arteriovenous shunts in infants: A decade of experience from a quaternary pediatric center

BACKGROUND AND PURPOSE

Intracranial arteriovenous shunts (IAVS) are rare vascular diseases in infants. They can be categorized into vein of Galen aneurysmal malformation (VGAM), pial arteriovenous fistula (PAVF), and dural arteriovenous fistula associated with dural sinus malformation (DAVF/DSM). We sought to review the clinical presentation, imaging characteristics, endovascular treatment (EVT), and outcomes of IAVS in infants presenting to a quaternary pediatric referral center over one decade.

METHODS

A retrospective review of a prospectively maintained database was performed of all infants diagnosed with IAVS between January 2011 and January 2021 in a quaternary pediatric referral center. For each patient, demographic data, clinical presentation, imaging findings, management strategies, and outcomes were reviewed and discussed.

RESULTS

Over the study period, 38 consecutive infants were diagnosed with IAVS. Patients with VGAM (23/38, 60.5%) presented with congenital heart failure (CHF) (14/23), hydrocephalus (4/23), and seizures (2/23), and three patients were asymptomatic. Eighteen patients with VGAM underwent EVT. Among those, 13 patients (72.2%) were successfully treated with an angiographic cure and three patients (3/18, 17%) died. Patients with PAVF (9/38, 23.7%) presented with CHF (5/9), intracranial hemorrhage (2/9), and seizures (2/9), and all of them were successfully treated endovascularly. Patients with Type I DAVF/DSM (4/6, 66.6%) presented with mass effect (2/4), cerebral venous hypertension (1/4), CHF (1/4), and cerebrofacial venous metameric syndrome (1/4). Patients with type II DAVF/DSM (2/6, 33.3%) presented with a thrill behind the ear. Patients with DAVF/DSM were treated endovascularly, five patients were cured, and one with type I DAVF/DSM died.

CONCLUSION

Intracranial arteriovenous shunts are rare but potentially life-threatening neurovascular pathologies in infants. Endovascular treatment is challenging but feasible in carefully selected patients.

Pediatric Interventional Neuroradiology

Pediatric neurovascular disorders can lead to substantial mortality and morbidity if not diagnosed early and adequately managed. Children with neurovascular diseases cannot be treated as small adults as the vascular and central nervous system anatomy, physiology, and pathologies in children differ greatly from those of adults. In addition, some neurovascular pathologies are seen exclusively in children such as aneurysmal malformation of the vein of Galen, pial fistulas, and dural fistulas in the context of dural sinus disease. In this review, we aim to present an overview of the common pediatric neurovascular diseases along with their endovascular management.

Doppler Ultrasound Flow Reversal in the Superior Sagittal Sinus to Detect Cerebral Venous Congestion in Vein of Galen Malformation

BACKGROUND AND PURPOSE

Vein of Galen malformation is a rare congenital cerebrovascular malformation. In affected patients, increased cerebral venous pressure constitutes an important etiologic factor for the development of brain parenchymal damage. The aim of this study was to investigate the potential of serial cerebral venous Doppler measurements to detect and monitor increased cerebral venous pressure.

MATERIALS AND METHODS

This was a retrospective monocentric analysis of ultrasound examinations within the first 9 months of life in patients with vein of Galen malformation admitted at <28 days of life. Categorization of perfusion waveforms in the superficial cerebral sinus and veins into 6 patterns was based on antero- and retrograde flow components. We performed an analysis of flow profiles across time and correlation with disease severity, clinical interventions, and congestion damage on cerebral MR imaging.

RESULTS

The study included 44 Doppler ultrasound examinations of the superior sagittal sinus and 36 examinations of the cortical veins from 7 patients. Doppler flow profiles before interventional therapy correlated with disease severity determined by the Bicêtre Neonatal Evaluation Score (Spearman ρ = -0.97, P = < .001). At this time, 4 of 7 patients (57.1%) showed a retrograde flow component in the superior sagittal sinus, whereas after embolization, none of the 6 treated patients presented with a retrograde flow component. Only patients with a high retrograde flow component (equal or more than one-third retrograde flow, n = 2) showed severe venous congestion damage on cerebral MR imaging.

CONCLUSIONS

Flow profiles in the superficial cerebral sinus and veins appear to be a useful tool to noninvasively detect and monitor cerebral venous congestion in vein of Galen malformation.

Rapid Ventricular Pacing Facilitates Transarterial Embolization in Vein of Galen Malformations

Background: Mural type vein of Galen malformation (mVOGM) is a congenital high flow arteriovenous shunt between choroidal arteries and the prosencephalic vein of Markowski leading to heart failure and hydrovenous disorder in children. Embolizing fistulous connections can be challenging and typically requires adjunctive techniques such as induced hypotension, balloon-assisted flow control, and creation of a coil basket. These maneuvers add time, complexity, and unpredictability. Rapid ventricular pacing (RVP) has been proposed as an alternative strategy with fewer drawbacks, but has not been well studied. The approach involves catheterizing the right ventricle with a pacing catheter connected to a temporary external pacemaker. Prior to embolization, RVP is initiated to lower cardiac output. Following embolization, pacing is discontinued, and the heart returns to sinus rhythm. Methods: We performed RVP in five mVOGM patients from 4/2020 through 7/2021. Accounting for multiple procedures, RVP was utilized in ten cases and twenty-six pedicles. Results: Ventricular capture was achieved in all instances and was well tolerated, without arrhythmia. Casting the arterial pedicle with liquid embolic immediately adjacent to, or traversing, the fistulous point was achieved in 9/10 cases. There were no procedural complications. In 1 case, creation of a coil basket in the venous pouch was required to achieve a stable arterial cast Conclusions: This report describes the largest case series utilizing RVP in mVOGM. The technique appears safe and well tolerated.

Genetic dysregulation of an endothelial Ras signaling network in vein of Galen malformations

To elucidate the pathogenesis of vein of Galen malformations (VOGMs), the most common and severe congenital brain arteriovenous malformation, we performed an integrated analysis of 310 VOGM proband-family exomes and 336,326 human cerebrovasculature single-cell transcriptomes. We found the Ras suppressor p120 RasGAP ( RASA1 ) harbored a genome-wide significant burden of loss-of-function de novo variants (p=4.79×10 ^-7 ). Rare, damaging transmitted variants were enriched in Ephrin receptor-B4 ( EPHB4 ) (p=1.22×10 ^-5 ), which cooperates with p120 RasGAP to limit Ras activation. Other probands had pathogenic variants in ACVRL1 , NOTCH1 , ITGB1 , and PTPN11 . ACVRL1 variants were also identified in a multi-generational VOGM pedigree. Integrative genomics defined developing endothelial cells as a key spatio-temporal locus of VOGM pathophysiology. Mice expressing a VOGM-specific EPHB4 kinase-domain missense variant exhibited constitutive endothelial Ras/ERK/MAPK activation and impaired hierarchical development of angiogenesis-regulated arterial-capillary-venous networks, but only when carrying a "second-hit" allele. These results illuminate human arterio-venous development and VOGM pathobiology and have clinical implications.

The composition of landmark vein of Galen malformation research: the emergence of endovascular treatments

BACKGROUND

Since the advent of endovascular treatment, the long-term prognosis of vein of Galen malformation (VOGM) has markedly improved; however, the nature of research leading to this point is unclear. The objective of this study was to define the composition of VOGM research to date, by means of a bibliometric analysis of the 100 most cited VOGM articles.

METHODS

An electronic search of Elsevier's Scopus database was performed to identify the 100 most cited articles on VOGM screened against predetermined criteria. Data were then compared.

RESULTS

The 100 most cited VOGM articles were published between 1974 and 2017 in 38 unique journals and originated from 16 unique countries. Mean citation count and rate were 59.4 citations and 2.9 citations/year, respectively. The USA (n = 42); Hôpital de Bicêtre, France (n = 15); and Dr. Pierre Lasjaunias (n = 16) were the largest individual country, institutional, and author contributors. Compared to the older articles (published < 2000), key differences for newer articles were statistically higher citation rates (P < 0.01), more authors (P < 0.01), higher proportion of endovascular treatment descriptions (P = 0.01), and more originating from Asia Pacific (P < 0.01).

CONCLUSIONS

From the 100 most cited VOGM articles to date, there has been a noticeable shift from diagnosing VOGM based on the foundational work by Dr. Lasjaunias to understanding how we can model clinical outcomes now that endovascular treatment has become the standard of care. Significant shifts in prognosis are pending, and the current bibliometric data implicate we are on the precipice of more recent works making an impact in the near future.

Vein of Galen Malformations in Adults

OBJECTIVE

Vein of Galen Malformations (VoGM) are rare vascular malformations, typically seen in pediatric age groups. Even more rarely, VoGM's may be seen later in adulthood. In this case report and systematic review, we provide a thorough description of the current literature as well as provide a case example exploring the diagnosis, imaging, treatment, and management of VoGM in adults.

METHODS

In accordance with PRISMA guidelines, we performed a systematic literature search for all relevant cases and case series of VoGM in adult patients. The reference list of all articles were reviewed for additional relevant cases. Articles were included if they described a VoGM of a patient over the age of 18 years old and published in English. 149 articles were originally identified and 26 described cases met our inclusion criteria.

RESULTS

In our literature review we found 26 patients that met our inclusion criteria. We found 14 male patients and 12 female patients. The mean age at presentation was 37.2 years (median=34 years, SD= 13.6 years). The most common presenting symptoms of patient were headache (n = 9), seizure (n = 6), and vomiting (n = 4). Of the 12 cases which clearly reported the subtype of VoGM, the choroidal type was more frequently seen (n = 10) compared to the mural type (n = 2). In 3 patients, the VoGM was thrombosed at time of diagnosis. Of the 26 patients, endovascular treatment was performed most frequently (n = 8) but some received microsurgical treatment (n = 4) or were treated conservatively (n = 6). Other treatment modalities included (ventriculoperitoneal shunt, ventriculostomy) (n = 5). In 3 cases treatment was not specified. In comparison to VoGM seen in pediatric or neonatal populations, VoGM in adults generally resulted in more favorable outcomes with only 2 patients reported to have passed away following treatment.

CONCLUSION

VoGM remains a rare finding amongst the adult population. Hence, we described the clinical presentation, treatment modalities, and outcomes of the cases described in the English literature. Perhaps due to the rate of thrombosis and the unique angioarchitecture seen in adult VoGM patients, outcomes were generally more favorable than those described in the literature in pediatric or neonate VoGM patients.

ETV as treatment for obstructive hydrocephalus in an aneurysmal malformation of the vein of Galen in infants: case report and review of literature

INTRODUCTION

A vein of Galen aneurysmal malformation (VGAM) is a high-flow arteriovenous malformation that typically presents in early childhood. Complications associated with this condition include heart failure and hydrodynamic disorders resulting from high blood flow. Hydrocephalus is one of the hydrodynamic disorders. It can present in a chronic form due to a defect in the absorption of cerebrospinal fluid (CSF) resulting from venous hypertension or in an acute/subacute form due to obstruction of normal circulation routes caused by the mass effect of the VGAM. Currently, endovascular closure of the lesion is considered the treatment of choice. However, in acute/subacute presentations of obstructive hydrocephalus, progression may occur despite endovascular treatment, necessitating a cerebrospinal fluid diversion procedure. Prior to the advent of endoscopic treatment, ventricular shunts were utilized, but outcomes were poor due to the pathological hydrodynamic parameters associated with the malformation. The role of endoscopic third ventriculostomy as a treatment option in these situations remains unclear, and there is limited literature available. Therefore, we present the case of a patient with a vein of Galen aneurysmal malformation and obstructive hydrocephalus, which was treated via ETV. Furthermore, a literature review was conducted.

CASE DESCRIPTION

We present a 5-month-old infant who was diagnosed at birth with VGAM. At 2 months of age, a partial closure of the malformation was performed via endovascular. Subsequently, the patient presented at the emergency department with symptoms of irritability, lethargy, vomiting, feeding refusal, and "setting sun" sign of several days' duration due to obstructive hydrocephalus. The patient was successfully treated via ETV. Following this, a new arteriography was performed and revealed occlusion of the VGAM. The child clinically improved and currently exhibits mild psychomotor impairment after 1-year follow-up.

CONCLUSION

In the literature, there are a limited number of reports on the treatment of obstructive hydrocephalus associated with VGAM via ETV. These reports have demonstrated good outcomes with minimal surgical complications. Our patient also exhibited good results. As such, ETV is a viable and safe option for the treatment of obstructive hydrocephalus associated with VGAM in pediatric patients. However, more research is needed to establish the effectiveness of ETV in comparison to other treatment options and to understand the long-term outcomes.

Vein of Galen aneurysmal malformation: rationalizing medical management of neonatal heart failure

Neonates who present in high output heart failure secondary to vein of Galen aneurysmal malformation can be difficult to manage medically due to the complex physiology that results from the large shunt through the malformation. Though the cardiac function is often normal, right ventricular dilation, severe pulmonary hypertension, and systemic steal can result in inadequate organ perfusion and shock. This report recommends medical management for stabilization of neonates prior to definitive management with endovascular embolization. IMPACT: Vein of Galen aneurysmal malformation (VGAM) is a rare intracranial arteriovenous malformation, which can present in the neonatal period with high output heart failure. Heart failure secondary to VGAM is often difficult to manage and is associated with high mortality and morbidity. Despite optimal medical management, many patients require urgent endovascular embolization for stabilization of their heart failure. This report offers discrete recommendations that can be used by clinicians as guidelines for the medical management of heart failure in newborns with VGAM.

Transvenous embolization of vein of galen aneurysmal malformations with coils as a final procedure for cure: A single-institution experience of 18 years

INTRODUCTION

Staged, transarterial embolization (TAE) is currently considered the gold standard for the treatment of vein of Galen aneurysmal malformation (VGAM); however, as transarterial access becomes restricted, further staged TAE may become ineffective or carry an increased risk of hemorrhagic or ischemic stroke when attempting complete obliteration.

OBJECTIVE

To describe the first consecutive, retrospective series of VGAM treated with transvenous embolization (TVE) with coils alone, as the final treatment in staged endovascular therapy, at a single institution between January 2004 and September 2021.

RESULTS

A total of 10 patients with a median age of 5.5 (IQR: 9.25) years were treated with coiling TVE. Patients were treated with a median number of 5 (IQR: 2.75) TAEs prior to the final TVE treatment. Complete or near-complete immediate angiographic obliteration was achieved in eight patients. Immediate post-procedural (within 48 h) hemorrhagic complications were noted in two patients (20%), one of whom passed away while the second suffered from hemiparesis. Stereotactic radiosurgery was performed in two patients with incomplete obliteration after TVE. The median follow-up time after TVE was 17 (IQR: 9) months. At long-term follow up (17 months) for the remaining nine patients, all VGAMs were completely obliterated. Long-term clinical deterioration compared to pre-TVE was noticed in one case.

CONCLUSION

Transvenous coil embolization is a technically feasible but risky option, as a final-stage treatment for cure of VGAMs with restricted trans-arterial access. Although TVE with coils remains an effective therapeutic modality, we recommend continuing investigation of safer TVE techniques to achieve cure.

Outcomes of endovascular embolization for Vein of Galen malformations: An individual participant data meta-analysis

Introduction

Understanding outcomes after Vein of Galen malformation (VOGM) embolization has been limited by small sample size in reported series and predominantly single center studies. To address these limitations, we perform an individual-participant meta-analysis (IPMA) to identify risk factors associated with all-cause mortality and clinical outcome after VOGM endovascular embolization.

Methods

We performed a systematic review and IPMA of VOGM endovascular outcomes according to PRISMA guidelines. Individual patient characteristics including demographic, intra/post-operative adverse events, treatment efficacy (partial or complete occlusion), and clinical outcome were collected. Mixed-effects logistic regression with random effects modeling and Bonferroni correction was used (p ≤ 0.003 threshold for statistical significance). The primary and secondary outcomes were all-cause mortality and poor clinical outcome (moderate/severe developmental delay or permanent disabling injury), respectively. Data are expressed as (mean ± standard deviation (SD)) or (odds ratio (OR), 95% confidence interval (CI), I 2, p-value).

Results

Thirty-five studies totaling 307 participants quantifying outcomes after endovascular embolization for VOGM were included. Follow up time was 42 (±57) months. Our analysis contained 42% neonates (<1 month) at first embolization, 45% infants (1 month ≤2 years), and 13% children (>2 years). Complete occlusion was reported in 48% of participants. Overall all-cause mortality was 16%. Overall, good clinical outcome was achieved in 68% of participants. First embolization as a neonate [OR = 6.93; 95% CI (1.99-24.08); I 2 < 0.01; p < 0.001] and incomplete embolization [OR = 10.87; 95% CI (1.86-63.55); I 2 < 0.01; p < 0.001] were associated with mortality. First embolization as a neonate [OR = 3.24; 95% CI (1.47-7.15); I 2 < 0.01; p < 0.001], incomplete embolization [OR = 5.26; 95% CI (2.06-13.43); I 2 < 0.01; p < 0.001], and heart failure at presentation [OR = 3.10; 95% CI (1.03-9.33); I 2 < 0.01; p = 0.002] were associated with poor clinical outcomes. Sex, angioarchitecture of lesion, embolization approach (transvenous vs. transarterial), and single or multistage embolization were not associated with mortality or clinical outcome.

Conclusions

We identify incomplete VOGM embolization independently associated with mortality and poor clinical outcome. While this study provides the highest level of evidence for VOGM embolization to date, prospective multicenter studies are needed to understand the optimal treatment strategies, outcomes, and natural history after VOGM embolization.

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.

Cerebral neurovascular embryology, anatomic variations, and congenital brain arteriovenous lesions

Cerebral neurovascular development is a complex and coordinated process driven by the changing spatial and temporal metabolic demands of the developing brain. Familiarity with the process is helpful in understanding neurovascular anatomic variants and congenital arteriovenous shunting lesions encountered in endovascular neuroradiological practice. Herein, the processes of vasculogenesis and angiogenesis are reviewed, followed by examination of the morphogenesis of the cerebral arterial and venous systems. Common arterial anatomic variants are reviewed with an emphasis on their development. Finally, endothelial genetic mutations affecting angiogenesis are examined to consider their probable role in the development of three types of congenital brain arteriovenous fistulas: vein of Galen malformations, pial arteriovenous fistulas, and dural sinus malformations.

The outcome of the vein of Galen aneurysmal malformation cases diagnosed prenatally

Vein of Galen aneurysmal malformation (VGAM) is a rare foetal anomaly associated with neurodevelopment delay, cardiac failure, and even perinatal death. We aimed to assess prenatal features of VGAM and describe postnatal outcomes. This was a retrospective study involving six foetuses diagnosed with VGAM prenatally in two centres. All of the cases underwent foetal neurosonography and echocardiography. The presence of ventriculomegaly, intracranial haemorrhage and cardiac failure was recorded. Pregnancy and neonatal outcome information were obtained from medical records. The mean gestational age at diagnosis was 31.1 ± 5.1 weeks, and the mean size of VGAM was 29.2 ± 5.2 × 26.4 ± 3.3 mm. Ventriculomegaly was detected in five of six (83.3%) cases. Intracranial haemorrhage was present in five (83.3%) cases. Cardiac failure was shown in four (66.6%) foetuses. Three foetuses underwent termination of pregnancy (TOP); in two cases, neonatal death occurred. One patient was treated with endovascular embolisation, and there was no cardiac problem or neurodevelopment delay. Prenatally diagnosed VGAM have a poor prognosis, mainly if a cardiac failure or neurological consequences (intracranial haemorrhage, hydrocephaly) are present in utero.Impact StatementWhat is already known on this subject? VGAM is the most common cerebral arteriovenous malformation detected prenatally, and it can lead to severe consequences in the perinatal period.What do the results of this study add? The accuracy of foetal neurosonography is excellent for detecting VGAM and associated brain abnormalities. Foetal echocardiography is mandatory for the prediction of prognosisWhat are the implications of these findings for clinical practice and/or further research? VGAM is associated with severe brain injury, cardiac failure, and the prognosis is generally poor. We need predictors to identify those expected to benefit from postnatal therapy.

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.

Review on the current treatment status of vein of Galen malformations and future directions in research and treatment

INTRODUCTION

Vein of Galen malformations (VOGMs) represent a rare pathologic entity with often catastrophic natural history. The advances in endovascular treatment in recent years have allowed for a paradigm shift in the treatment and outcome of these high-flow shunts, even though their pathogenetic mechanisms and evolution remain in part obscure.

AREAS COVERED

The overall management of VOGMs requires a tailored case-to-case approach, starting with in utero detection and reserving endovascular treatment for indicated cases. Lately, the advances in translational research with whole-genome sequencing and the coupling with cellular-level hemodynamics attempt to shed more light in the pathogenesis and evolution of these lesions. At the same time the advances in endovascular techniques allow for more safety and tailored technical strategy planning. Furthermore, the advances in MRI techniques allow a better understanding of their vascular anatomy. In view of these recent advances and by performing a PUBMED literature review of the last 15 years, we attempt a review of the evolutions in the imaging, management, endovascular treatment and understanding of underlying mechanisms for VOGMs.

EXPERT OPINION

The progress in the fields detailed in this review appears very promising in better understanding VOGMs and expanding the available therapeutic arsenal.

High Output Cardiovascular Physiology and Outcomes in Fetal Diagnosis of Vein of Galen Malformation

Vein of Galen aneurysmal malformation (VGAM) is a rare anomaly associated with poor outcomes from high output cardiac failure and neurologic complications. Studies addressing fetal cardiovascular status and outcomes in this population are limited. A single-center retrospective review was conducted on patients with a prenatal diagnosis of VGAM who underwent a fetal echocardiogram between January 2015 and July 2019. Fetal echocardiographic data, brain magnetic resonance imaging (MRI) findings and outcomes were collected. Nine fetuses [median gestational age at echocardiogram 34 (1.1) weeks] were included. All patients had superior vena cava dilation and reversal of diastolic flow in the transverse aortic arch. Median cardiothoracic (CT) ratio was 0.39 (0.09). Right ventricular (RV) and left ventricular (LV) dysfunction was present in 66% and 11% fetuses, respectively. Four out of five patients that underwent postnatal endovascular neurosurgical interventions at our center were alive at follow-up (mean 2.7 years). Of the non-survivors (n = 5), 3 received comfort care because of severe brain damage and died in the neonatal period. Non-survivors more commonly had > mild tricuspid regurgitation (TR) (40% vs. 25%) and > mild RV dilation (60% vs. 25%). Combined cardiac index (CCI) was higher in non-survivors when compared to survivors (672.7 vs. 530.2 ml/kg/min, p = 0.016). Fetuses with significant parenchymal damage on brain MRI tended to have a higher CCI than those without (979.8 vs. 605.0 ml/kg/min, p = 0.047). RV dysfunction, TR and elevated CCI are more commonly seen in non-survivors with VGAM. A higher CCI is seen in those deemed untreatable due to significant parenchymal volume loss. Future multicenter studies are needed to assess for prenatal prediction of outcomes in this high-risk population.

Epidemiology, Diagnostics, and Management of Vein of Galen Malformation

BACKGROUND

Vein of Galen malformation (VGM) is a rare congenital intracerebral vascular malformation. The aim of this study was to gain reliable data about epidemiology; clinical manifestations; and pre-, peri- and postinterventional treatment strategies in Germany.

METHODS

This prospective epidemiologic study was conducted by Erhebungseinheit für Seltene Pädiatrische Erkrankungen in Deutschland, a hospital-based German nationwide surveillance unit for rare pediatric diseases. Patients aged upto 18 years with a new diagnosis of VGM were prospectively included between January 1, 2014 and December 31, 2015.

RESULTS

In the two-year study period, 30 individuals with newly diagnosed VGM were identified, resulting in an estimated annual incidence rate of VGM in Germany of at least 1: 58,100 live births. The main symptoms were age dependent. Neonates presented with mainly cardiac manifestations of high output failure; infants and older children mainly suffered from neurological complications. Of the patients with endovascular treatment 95% survived, but only 41% of these patients were discharged home without any complications. The Bicêtre Neonatal Evaluation Score was a good predictor for poor outcome but could have led to palliative care in some patients with good outcome.

CONCLUSIONS

The incidence of VGM in Germany is estimated to be 1:58,100 live births. The majority of patients were eligible for endovascular treatment. Nevertheless, due to side effects and long-term sequelae in the majority of patients, further improvement in care of children with VGM is needed.

Eponyms in Vascular Neurosurgery: Comprehensive Review of 18 Veins

This review is the first comprehensive anatomic report of all venous eponyms used in vascular neurosurgery and provides the historical context of their authors as well as the surgical relevance of every structure. A PubMed literature review identified 13 individuals for whom 18 eponymous venous structures of the brain were named. These structures are the Batson plexus, veins of Breschet, Breschet sinus, vein of Dandy, vein of Galen, prosencephalic vein of Markowski, torcular Herophili, vein of Labbé, venous plexus of Rektorzik, vein of Rolando, basal vein of Rosenthal, sylvian veins, lateral lakes of Trolard, vein of Trolard, hypoglossal plexus of Trolard, petro-occipital vein of Trolard, venous circle of Trolard, and the vein of Vesalius. Eponyms provide a valuable shorthand that encompasses anatomic nuances, variabilities, and surgical relevance. In addition, they elucidate the historical context in which these structures were described and are an academic honor to our predecessors.

Coil assisted glue embolization to improve safety and accuracy in endovascular management of Vein of Galen patients

BACKGROUND

Vein of Galen malformation (VOGM) patients present in neonatal age with cardiac failure or significant neurologic consequences. The most established method of treatment has been transarterial embolization with high concentration glue (N-Butyl Cyano Acrylate) which may be difficult to control due to very high flow rates and may migrate to the venous side with undesirable consequences. We describe our experience in four patients in whom initial coil placement in prominent feeding arteries helped inflow reduction thereby facilitating controlled glue injection with a good result and no incidence of non-target embolization.

MATERIALS AND METHODS

Four neonates who had presented during the last three years with cardiac failure were included in the study. Prominent feeders identified on imaging or DSA were treated with transarterial helical coil placement in the terminal segment just before the VOGM sac followed by controlled glue injection. The outcome was assessed by detailed clinical and imaging follow-up.

RESULTS

A total of 10 most prominent feeders were embolized in four patients. Complete embolization of the VOGM was achieved in two patients in a single session. One patient with residual small feeders showed subsequent thrombosis of these feeders, possibly secondary to flow reduction in the sac. One patient still shows thin residual feeders but good clinical improvement and is being planned for follow-up and a second session at one year of age. No complications were observed. All patients showed immediate improvement in cardiac failure and good neurological development on follow-up. On imaging, the VOGM sac regressed completely (3 patients) or significantly in size (1 patient).

CONCLUSION

Planned coil placement in the terminal part of prominent feeding arteries reduced the flow and provided lattice on which glue deposits in a controlled manner without any incidence of non-target embolization in our study. This relatively less described technique increases the safety and accuracy of the endovascular treatment in VOGM patients.

Factors Contributing to Major Neurological Complications From Vein of Galen Malformation Embolization

Importance

Major neurological complications from the embolization of vein of Galen malformations (VOGMs) are poorly understood. We provide a detailed analysis of contributors to periprocedural neurological complications and lessons learned.

Objective

To assess the rate of major periprocedural neurological complications following VOGM embolization with major procedural and strategic contributors.

Design, Setting, and Participants

This retrospective cohort study was conducted at a quarternary referral pediatric hospital (Hospital for Sick Children; Toronto, Ontario, Canada) from January 1999 to December 2018 with a mean clinical follow-up of 44.7 months; all children with VOGM diagnosed and/or treated were eligible (n = 48). Thirty-three patients who underwent endovascular treatment were included.

Interventions

Endovascular staged transarterial embolization performed in 33 patients over 91 sessions.

Main Outcomes and Measures

The primary outcome was the rate of periprocedural neurological complications (occurring within 1 week of embolization). The secondary outcomes were mortality, long-term neurological outcomes, and contributing anatomical and management factors to neurological complications.

Results

Of 33 patients who underwent embolization (31 boys [64.6%]; 17 girls [35.4%]; median age at first embolization, 4 months [range, 0-29 months]), 10 patients (30.3%) developed major periprocedural neurological complications. Five of these patients died. Univariate logistic regression analyses identified internal cerebral vein drainage to the main venous sac of the VOGM and use of a microcatheter with a distal outer diameter of more than 2.0F as significant predictors of poor neurological outcomes. Lessons learned from our experience include the need to assess the internal cerebral vein drainage pattern on preprocedural magnetic resonance venography, avoidance of excessive embolization into the venous sac, treatment of more distal fistulae before proximal fistulae to avoid a sump effect, and preferably use of smaller (<2.0F outer diameter) microcatheters in neonatal embolization procedures.

Conclusions and Relevance

In this cohort, 10 patients with VOGM treated with embolization (30.3%) experienced major periprocedural neurological complications, half of whom died. While these outcomes are superior to historic conservative and surgical treatment results, ongoing improvements in treatment and pretreatment diagnostic approaches are needed. Awareness of the lessons learned from our experience can help to avoid similar complications in the future for this vulnerable population.

Management of Jugular Bulb Stenosis in Pediatric Vein of Galen Malformation: A Novel Management Paradigm

INTRODUCTION

Pediatric vein of Galen malformations (VOGMs) are fistulous intracranial malformations arising congenitally within the choroidal fissure that can present with an array of neurological and cardiac sequelae. Associated venous stenosis may result in intracranial venous hypertension and ischemia leading to severe, irreversible cerebral injury. Management of neonatal VOGMs typically involves staged embolization and angioplasty/stenting for relief of venous stenosis. Rarely, jugular foraminal narrowing has been identified as causing jugular bulb stenosis.

CASE PRESENTATION

We present the case of a 22-month-old female diagnosed with VOGM prenatally who displayed persistent intracranial venous hypertension despite multiple neuroembolization procedures during the neonatal period. Following initial reduction in arteriovenous shunting, she once again developed venous hypertension secondary to jugular bulb stenosis for which angioplasty was attempted. Failure of angioplasty to relieve the venous hypertension prompted skull base imaging, which revealed jugular foraminal ossification and stenosis. Microsurgical jugular foraminotomy followed by balloon angioplasty and stenting significantly reduced jugular pressure gradients. Restenosis requiring re-stenting developed postoperatively at 9 months, but the patient has remained stable with significant improvement in cortical venous congestion.

DISCUSSION/CONCLUSION

This case demonstrates the efficacy of microsurgical decompression of the jugular foramen and endovascular angioplasty/stenting as a novel treatment paradigm for the management of intracranial venous hypertension in the setting of VOGM.

Neurovascular disease and syndromes: Diagnosis and therapy in children

The pediatric neurovascular disease runs the chronologic spectrum with dramatic changes in the presentation, evaluation, and treatment from the prenatal, perinatal, and infant periods through childhood and adolescence. These diseases are often dynamic throughout this period and the dynamic continues throughout life. There are four major categories: high-flow arteriovenous shunting lesions, arterial aneurysms, low-flow vascular lesions, and vascular occlusive disease. The high-flow lesions can be subdivided into a vein of Galen malformation, non-Galenic arteriovenous fistula, dural sinus malformations and fistula, and arteriovenous malformation. Low-flow vascular lesions include cerebral cavernous malformation, developmental venous anomaly, and capillary telangiectasia. The cerebrovascular occlusive disease can be divided between arterial occlusive disease and cerebral venous sinus thrombosis. The presentation of each of these entities can be very similar, especially in younger children; however, imaging and laboratory analysis can establish the diagnosis leading to the most appropriate therapy. A multidisciplinary team, dedicated to treating pediatric cerebrovascular disease, is important in delivering the best outcomes in these complex diseases. Given the relative rarity of pediatric presentation of cerebrovascular disease, many apply adult concepts to children. A better understanding of the diseases and their difference from adults makes a critical difference in selecting the correct approach.

Variations of Intracranial Dural Venous Sinus Diameters from Birth to 20 Years of Age: An MRV-Based Study

BACKGROUND AND PURPOSE

The role of the dural venous sinus system in cerebrovascular pathology and the understanding of normal developmental patterns and sizes of the dural venous sinus system continue to expand. The purpose of this study was to review MR venograms to elucidate developmental patterns and diameters of the major dural venous sinuses from 0 to 20 years of age.

MATERIALS AND METHODS

All available MR venograms of patients 0-20  years of age who presented to our institution were retrospectively reviewed. Patient age at the time of image acquisition was noted, and measurements were taken of the diameters of the major dural venous sinuses. The presence of embryonic sinuses including the persistent falcine sinus and the occipital sinus was noted. Dominance patterns of the transverse sinus system were determined. Mean diameters of each sinus were plotted as a function of age. The prevalence of persistent prenatal sinuses and transverse sinus-dominance patterns was compared across ages.

RESULTS

A total of 429 MR venograms from 429 patients were reviewed. All dural venous sinuses demonstrated a maximal growth rate from 0 to 7 years of age and reached maximal diameters around 5-10 years of age. The prevalence of falcine sinuses and occipital sinuses trended downward across increasing age categories (P = .09 and, <.0001, respectively).

CONCLUSIONS

Dural venous sinuses demonstrate maximal growth between 0 and 7 years of age and reach adult size around 5-10 years of age. Involution of the prenatal sinuses continues to take place after birth into childhood but is largely absent in early adulthood.

Anatomical implications of posterior cephaloceles in the dural venous sinuses

OBJECTIVE

To analyze the venous anatomy of the dural sinuses of patients with posterior encephaloceles, in order to formulate anatomical patterns which can ensure safer surgery.

METHODS

This is a retrospective study, analyzing eight patients diagnosed with posterior encephalocele throughout 1 year.

RESULTS

Eight patients with cephaloceles were evaluated in our study from January 2017 to January 2018. The most common alteration was dysgenesis of the straight sinus (n = 7), followed by venous anomalies in the encephalocele and alterations in the SSS (superior sagittal sinus) (n = 4), and the occurrence of a falcine sinus (FC) in 3 patients.

CONCLUSION

Anatomical variations are frequent in patients with cephaloceles. Therefore, an understanding of them is necessary for safe and effective treatment.

Vein of Galen Malformations: The Texas Children's Hospital Experience in the Modern Endovascular Era

BACKGROUND

Vein of Galen malformations (VOGM) comprise nearly a third of pediatric cerebrovascular anomalies, with potentially devastating neurological and systemic complications. Advances in endovascular therapies have dramatically improved outcomes compared to historical surgical treatments, and neurosurgeons are an essential component of the multidisciplinary critical care team.

OBJECTIVE

To retrospectively review pediatric patients with VOGM treated at Texas Children's Hospital (TCH), a quaternary referral center, over 15 yr, and present lessons learned in treating children with modern endovascular techniques.

METHODS

Charts from TCH were retrospectively reviewed for the past 15 yr. Patients with diagnosis including "Vein of Galen," "Vein of Galen malformation," "Vein of Galen aneurysmal malformation," or any abbreviations (ie, VOG, VOGM, VOGAM) were reviewed. Presentation, imaging, treatment specifics, and clinical outcomes were reported.

RESULTS

There were 18 patients with VOGM managed at TCH from 2002 to 2018 with a total of 29 embolizations. Seventeen were performed with a single embolisate (NBCA or Onyx), and 12 with a combination. A dual lumen balloon catheter was used as an adjunct in 3 embolizations. Complications occurred in 5 embolizations (24%), including hemorrhage, embolisate migration, and femoral vessel occlusion. Surviving patients were followed for a mean of 38 mo, with 12 having normal or near-normal neurological development.

CONCLUSION

VOGM can present with a myriad of neurological and systemic symptoms, potentially in extremis. Neurosurgical involvement in these cases is critical, as urgent treatment can be lifesaving. Patients may require multiple treatment sessions using a variety of endovascular tools and techniques.

Topographical anatomy of the tentorium cerebelli and venous confluences in human midterm fetuses

Early development of veins and sinuses at and around the posterior cranial fossa seemed not to be shown by photographs except for our recent study (Ann Anat, 2020). Examination of histological sections of 38 fetuses at 10-16 weeks gestational age (GA) demonstrated that: (1) the superior petrosal sinus passed posterosuperiorly through the tentorium cerebelli and, distant and lateral to both the cerebellum and internal ear, drained into the transverse sinus; (2) the superior sagittal sinus was underdeveloped, and the inferior sagittal sinus was not yet evident; (3) the straight sinus (STS) originated from a joining of the bilateral pial veins from the lateral ventricular choroid plexus, passed through the inferoposterior part of the falx cerebri, reached the initial confluens sinuum, and then divided into the bilateral transverse sinuses. The STS origin was immediately behind the pineal body, and near the inferoposterior end of the third ventricle. The falx had a thick attachment to the tentorium below the entire course of the STS and was behind other parts of the brain. Therefore, the development and growth of the posterior dural system seemed to be independent from brain growth, and occurred well before the cerebellum grew to fill the posterior cranial fossa. A basic configuration of intracranial veins and sinuses, including embryonic transient veins (such as the vena capitis prima) seemed to be established by venous return from the choroid plexus and cranial wall, without greatly increasing the abundance of neuronal or glial cells in the brain.

Intracranial venous malformations: Incidence and characterization in a large pediatric cohort

BACKGROUND

Significant advances have been reported recently in the genetic and mechanistic characterization of extracranial venous malformations. However, intracranial purely venous malformations (icVM) analogous to those outside the CNS have not been systematically described.

PURPOSE

We sought to ascertain whether such an entity as icVM could in fact be identified, distinct from previously described CNS venous anomalies and analogous to extracranial venous malformations.

METHODS

Our prospectively collected pediatric cerebrovascular database was reviewed to identify patients with icVM; 1458 consecutive angiograms and/or angiographic interventions performed on 706 children at our institution from October, 2006 through May, 2019 were evaluated, in addition to outside imaging studies on 192 additional patients sent to our Vascular Anomalies Center for cerebrovascular review during the same time period. Thus, the cohort consisted of 898 children.

RESULTS

Nineteen of 898 patients (2.1%) were found to harbor icVM, including 9 (47.3%) with sinus pericranii, 15 (78.9%) with associated large, complex extracranial venous malformations, and 3 (15.7%) with neurocognitive delay. There was no intracranial hemorrhage or venous hypertension seen in the cohort. Asymptomatic venous thrombosis in the superior sagittal sinus was seen in three patients.

CONCLUSION

Venous malformations, both extracranial and icVM, share many characteristics that are distinct from developmental venous anomalies. icVM were not associated with venous hypertension. The underlying genetic mutations involved in the development of icVM, germ-line or somatic, remain to be elucidated, but may very well involve shared mechanisms and pathways with extracranial venous malformations.

Arteriovenous fistulas of the Vein of Galen region in adults: Endovascular treatment

PURPOSE

Arteriovenous fistulas of the Vein of Galen region in adults (Ad-VGAVF) are an uncommon entity with specific anatomic features. The aim of this article is to present our experience in the endovascular treatment of this pathology and to propose a therapeutic strategy based precisely on the angioarchitecture of these lesions.

MATERIALS AND METHODS

During a 20-year period, 10 patients underwent endovascular treatment of Ad-VGAVF. They were nine men and one woman with a mean age of 50 years (23-66 years) treated with the same embolization strategy. Clinical presentation, angiographic characteristics, therapeutic strategy, and clinical outcomes were recorded.

RESULTS

All patients were treated exclusively by endovascular approach. Transarterial access was performed in eight patients and combined transvenous and transarterial access in two. Complete obliteration of the fistula was obtained in all patients. There were no intraprocedural complications. Post-embolization neurological symptoms occurred in 5 of 10 with complete resolution at six months in all of them.

CONCLUSION

Arteriovenous fistulas of the Vein of Galen region in adults present uniform angioarchitecture despite their low prevalence. Based on this constant angioarchitecture and especially on the features of its venous drainage, judicious embolization strategy is feasible and effective. Ten cases treated entirely by endovascular approach with excellent clinical and angiographic outcomes show this treatment like a curative alternative for this entity of deep topography and severe prognosis.

Deep venous communication in vein of Galen malformations: incidence, Imaging, and Implications for treatment

BACKGROUND

Failure to appreciate deep venous drainage pathways is a major cause of severe complications in the endovascular treatment of vein of Galen aneurysmal malformations (VOGMs).

OBJECTIVE

To report deep venous drainage patterns in patients with VOGM, emphasizing the internal cerebral veins, and to describe the challenges in evaluating these.

METHODS

Patients with VOGM presenting to our institute between 2000 and 2018 were retrospectively analyzed. Patients with complete and good quality imaging datasets were included in the study. Three neuroradiologists with expertise in the subject independently analyzed the deep venous drainage patterns on multi-sequence MRI and digital subtraction angiography. Follow-up imaging studies were analyzed for alterations in deep venous drainage patterns that occurred following endovascular treatment. Descriptive statistics were used to report findings.

RESULTS

Twenty-three patients had optimal quality MRI imaging and 25 had optimal quality DSA imaging available. In 14/23 (61%) patients, internal cerebral vein (ICV) communication could be reliably identified on MRI and in 8/25 (32%) patients on DSA. Deep venous communication with the VOGM was demonstrated in 8/26 (30.8%) patients. One (3.8%) patient demonstrated ICV communication with the VOGM only on postoperative imaging, while in 2 (8%) patients the ICV drainage route changed from VOGM to alternative pathways after the procedure. Other variant pathways included lateral mesencephalic vein, superior or inferior sagittal sinus, anterior mesencephalic vein, tentorial sinus, deep Sylvian vein, and superior vermian vein.

CONCLUSION

ICV communication with the VOGM is not uncommon and requires dedicated preprocedural imaging to identify it. However, there are significant challenges in assessing this communication in the presence of high-flow fistulae, vessel tortuosity and size, and contrast limitations in this population.

Fetal and Neonatal MRI Predictors of Aggressive Early Clinical Course in Vein of Galen Malformation

BACKGROUND AND PURPOSE

Neonates with vein of Galen malformations are split into 2 cohorts: one needing urgent neonatal embolization, with relatively high mortality and morbidity even with expert care, and a cohort in which embolization can be deferred until infancy, with far better prognosis. We aimed to identify brain MR imaging characteristics obtained from fetal and early neonatal scans that can predict the clinical presentation.

MATERIALS AND METHODS

Patients with vein of Galen malformations were stratified into a neonatal at-risk cohort if the patient needed urgent neonatal intervention or if neonatal death occurred; or an infantile treatment cohort if they were stable enough not to require treatment until >1 month of age. Twelve vascular MR imaging parameters, measured by 2 independent observers, were systematically correlated with the need for early neonatal intervention and/or neonatal mortality.

RESULTS

A total of 32 neonatal patients (21 patients in the neonatal at-risk cohort, 11 in the infantile treatment cohort) were identified. Maximal mediolateral diameter (area under the curve  = 0.866, P < .001) and cross-sectional area (area under the curve = 0.836, P = .002) at the narrowest point of the straight or falcine sinus were most predictive of clinical evolution into the neonatal at-risk cohort. There were 15 patients who had fetal MRIs (10 in the neonatal at-risk cohort and 5 in the infantile treatment cohort). Here too, maximal mediolateral diameter (area under the curve = 0.980, P = .003) and cross-sectional area (area under the curve  = 0.941, P = .007) at the narrowest point of the straight or falcine sinus were highly predictive of the neonatal at-risk cohort.

CONCLUSIONS

Early neonatal and fetal MR imaging can be readily used for accurate early risk stratification, assisting in directing resources, timing treatment decisions, and identifying appropriate cohorts for novel interventions.

Endoscopic Third Ventriculostomy in an Untreated Vein of Galen Malformation Presenting Lately with Acute Obstructive Hydrocephalus

BACKGROUND

Mural-type vein of Galen malformations (VoGMs) mostly manifest in later stages of infancy as macrocephaly, hydrocephalus, or failure to thrive unless previously diagnosed and treated. Literature is extremely limited on the success and safety of endoscopic third ventriculostomy (ETV) in acute obstructive hydrocephalus caused by an untreated VoGM. Thus, we aimed to present a case for demonstrating the possible efficacy and safety of ETV under such conditions.

CASE DESCRIPTION

A 22-month-old boy presenting with acute-onset headache, vomiting, and lethargy was diagnosed with a mural-type VoGM and acute obstructive hydrocephalus. He was treated satisfactorily with ETV and endovascular embolization. We observed a shrinkage in malformation sac diameter of >20 mm in the magnetic resonance imaging angiography at postoperative year 1. The child showed normal motor and mental development at his outpatient clinic visit at postoperative month 15.

CONCLUSIONS

To the best of our knowledge, this is the first case in the literature with an untreated VoGM presenting with acute obstructive hydrocephalus who was treated with the combination of ETV and endovascular embolization and had an adequate follow-up period.

The Impact of Angiographic Geometry on the Clinical Presentation of True Vein of Galen Aneurysmal Malformations

BACKGROUND PURPOSE

Vein of Galen aneurysmal malformations (VGAM) may carry life-threatening and catastrophic sequelae in children. Their clinical presentations are differently variable between cardiac and cerebral syndromes. There may be a possible relationship between the Galenic angioarchitecture and the clinical presentation. We aimed to study the effect of the venous outflow impairment on the incidence of high-flow heart failure and the incidence of hydrocephalus.

MATERIALS AND METHODS

The angiographies of 21 patients with true VGAM have been studied. MR angiography, 3-dimensional CT angiogram (3D CTA), and conventional digital subtraction angiography were performed for all patients with true VGAM. Transarterial embolization was done in 1 or more sessions for all cases.

RESULTS

Among the 21 cases, 14 cases were mural type, 5 cases were choroidal type, and 2 cases were mixed. Hydrocephalus was observed more in infants (92.3%), mural types (92.9%), giant and supergiant (87.5%) aneurysms, and in cases with persistent limbic circle (90.91%). All cases of hydrocephalus were associated with significant stenosis (>70%) of the Falcine sinus draining system (100%).

CONCLUSION

Significant stenosis (>70%) of the draining sinus is a significant factor for VGAM aneurysmal enlargement and occurrence of hydrocephalus. Probably, venous outflow impairment decreases the incidence of high-flow heart failure and increases the incidence of hydrocephalus.