Intracranial pial arteriovenous fistula in infancy: a case report and literature review

Pediatric non-galenic pial arteriovenous fistula's characteristics and outcomes: a systematic review

INTRODUCTION

Pediatric non-galenic pial arteriovenous fistulas (pAVFs) are rare vascular malformations that are characterized by a pial arterial-venous connection without an intervening capillary bed. Outcomes and treatment strategies for pAVFs are highly individualized, owing to the rarity of the disease and lack of large-scale data guiding optimal treatment approaches.

METHODS

We performed a systematic review of pediatric patients (< 18 years at diagnosis) diagnosed with a pAVF by digital subtraction angiogram (DSA). The demographics, treatment modalities, and outcomes were documented for each patient and clinical outcome data was collected. Descriptive information stratified by outcome scores were classified as follows: 1 = excellent (no deficit and full premorbid activity), 2 = good (mild deficit and full premorbid activity), 3 = fair (moderate deficit and impaired activity), 4 = poor (severe deficit and dependent on others), 5 = death.

RESULTS

A total of 87 studies involving 231 patients were identified. Median age at diagnosis was 3 years (neonates to 18 years). There was slight male preponderance (55.4%), and 150 subjects (81.1%*) experienced excellent outcomes after treatment. Of the 189 patients treated using endovascular approaches, 80.3% experienced excellent outcomes and of the 15 patients surgically treated subjects 75% had an excellent outcome. The highest rate of excellent outcomes was achieved in patients treated with Onyx (95.2%) and other forms of EvOH (100%). High output heart failure and comorbid vascular lesions tended to result in worse outcomes, with only 54.2% and 68% of subjects experiencing an excellent outcome, respectively. *Outcomes were reported in only 185 patients.

CONCLUSION

pAVFs are rare lesions, necessitating aggregation of patient data to inform natural history and optimal treatment strategies. This review summarizes the current literature on pAVF in children, where children presenting with heart failure as a result of high flow through the lesion were less likely to experience an excellent outcome. Prospective, large-scale studies would further characterize pediatric pAVFs and enable quantitative analysis of outcomes to inform best treatment practices.

Spontaneous thrombosis of high flow pediatric arteriovenous fistulae: Case series of two patients and a comprehensive literature review

Pediatric pial arteriovenous shunts in the brain and spine are challenging to understand because of low incidence, variable presentation, and associations with genetic syndromes. What is known about their natural history comes from reviews of small series. To better understand the natural history and role for intervention, two cases are presented followed by a review of the literature. In the first case, an infant with a prior history of intracranial hemorrhage from a ruptured pial fistula returns for elective embolization for a second pial fistula which was found to be spontaneously thrombosed 2 weeks later. In the second case, a 5-year-old with a vertebro-vertebral fistula, identified on work up for a heart murmur and documented with diagnostic angiography, is brought for elective embolization 6 weeks later where spontaneous thrombosis is identified. In reviewing the literature on pediatric single-hole fistulae of the brain and spine, the authors offer some morphologic considerations for identifying which high-flow fistulae may undergo spontaneous thrombosis to decrease the potentially unnecessary risk associated with interventions in small children.

Expect the unexpected: a case of spontaneous thrombosis of a pial arteriovenous fistula in a preterm newborn with review of the literature

INTRODUCTION

Pial arteriovenous fistulas (pAVF) are rare vascular malformations, especially in children and newborns. In neonates, the most common symptom is congestive heart failure.

CASE PRESENTATION

We report a case of an asymptomatic preterm newborn incidentally diagnosed with pAVF during a routine cranial ultrasound (cUS) on the third day of life. Cerebral magnetic resonance (MRI) confirmed the diagnosis. A wait-and-see approach was chosen by the multidisciplinary team. The cUS and the MRI on day 14 of life showed the spontaneous resolution of the lesion.

CONCLUSIONS

This case underlines the challenges in identifying pAVF in the first weeks of life and demonstrates a possible positive outcome for affected neonates.

A Systematic Review of Non-Galenic Pial Arteriovenous Fistulas

OBJECTIVE

Non-galenic pial arteriovenous fistulas (NGPAVFs) are rare cerebrovascular pathologies accounting for only 1.6%-4.8% of all brain vascular malformations. We performed a comprehensive review of NGPAVF cases reported in the literature to further characterize their clinical patterns of presentation, angiographic features, management, clinical outcomes, and complications.

METHODS

We searched PubMed, Google Scholar, and Embase from each database's earliest records to April 2022 for all relevant English language articles. A total of 3280 articles were screened to identify those that met prespecified inclusion criteria. Differences in clinical outcomes between children (≤18 years old) and adults (>18 years old) and those articles in which NGPAVFs were associated with the presence of a varix or a hemorrhage were statistically examined.

RESULTS

A total of 242 patients in 86 articles were included. The mean patient age was 18.51 ± 18.80 years. The male-to-female ratio was 1.44:1. Headache was the most common initial presentation (42.6%) in the study cohort. Hemorrhage occurred at a significantly higher frequency in adults (P = 0.004), whereas more children presented with congestive heart failure (P < 0.001). Surgical, endovascular, and combination therapy led to comparable rates of complete NGPAVF obliteration (86.8%, 85.2%, and 88.5%, respectively). Fifty-nine patients (24.4%) experienced a complication, ranging from minor neurological deficit to severe hemorrhage. The mortality rate for the overall cohort was 3.3%, and all deceased patients had a varix associated with their fistulas.

CONCLUSIONS

To our knowledge, we report the largest literature review describing the clinical course and characteristics of NGPAVFs. All treatment approaches resulted in favorable obliteration rates and overall patient outcomes.

Neonatal bilateral cerebral high flow fistulae leading to detection of a HHT-family carrier

Cerebral and spinal cord high-flow arteriovenous fistulae (HFAVF) are part of the spectrum of lesions found in Hereditary Hemorrhagic Telangiectasia (HHT). HFAVF consist of communications between large arteries and veins without interposed nidi or capillary transitions. The association between HHT and cerebral or spinal HFAVF in children has been reported and suggested as a potential marker for HHT. We present a newborn with bilateral intracranial HFAVF tested positive for HHT1 and belonging to a family non known for carrying a HHT mutation. We also review reported cases of neonates and infants with cerebral and spinal HFAVF emphasizing their associations with genetic syndromes. Our aim is to add a new case to the pertinent literature and emphasize the need for molecular testing in children with spinal or brain HFAVF.

Pediatric pial arteriovenous fistula located at the bottom of the callosal sulcus presenting with intraventricular hemorrhage: a case report and literature review

BACKGROUND

A pial arteriovenous fistula (pAVF) is a rare condition characterized by a direct connection between a cerebral artery and cerebral vein without an intervening nidus. The prognosis is poor in untreated cases with hemorrhagic manifestations, indicating that surgical treatment is desirable. We describe a successful endovascular treatment for a pediatric case of ruptured pAVF located at the bottom of the sulcus.

CLINICAL DESCRIPTION

An 11-year-old girl presented with severe headache and mild disturbance of consciousness. Head computed tomography showed hemorrhage in the callosal sulcus and ventricle. Cerebral angiography showed an arteriovenous shunt without a nidus. The branching artery from the pericallosal artery was connected directly to the thalamostriate vein without varix, and the shunt point was located at the bottom of the callosal sulcus. The patient was diagnosed with pAVF involving a single feeder and single drainer. Emergency endovascular transarterial embolization was performed using 20% N-butyl cyanoacrylate, and the shunt disappeared completely without complications. The patient was discharged with no neurological deficits.

CONCLUSION

Endovascular treatment is feasible, safe, and effective for pediatric cases of deeply located pAVF.

Hemorrhagic Cerebrovascular Pathology in the Pediatric Population

Hemorrhagic cerebrovascular disease in the pediatric population can have devastating and long-term effects. Progress in the fields of genetics, neuroimaging, pharmacology, and surgical techniques has led to improved diagnosis and management of pediatric cerebrovascular diseases. In this review we discuss the current etiologies and medical and surgical treatments of hemorrhagic cerebrovascular pathology affecting infants and children. A special emphasis is placed on neuroendovascular treatment options. Increased knowledge about this unique pathology and the medical and therapeutic options will empower practitioners to more quickly and accurately identify and accurately treat hemorrhagic diseases in the pediatric population.

Congenital pial AVF along the falx cerebri with complete agenesis of the corpus callosum and bilateral parasagittal pachygyria-polymicrogyria secondary to chronic ischemia

OBJECTIVE

Pial arteriovenous fistula (AVF) is an extremely rare entity due to direct arterial connection with the venous plexus without an intervening capillary network. The objective of this article is to describe a unique case of congenital pial AVF along the interhemispheric falx with complete callosal agenesis and malformation of cortical development within the bilateral anterior cerebral artery territories. We also demonstrated the distinctive feature of temporal stability of the extensive intracranial abnormalities without active intervention. Less than 100 cases have been reported thus far, most of which involve the adult rather than pediatric age group. A comprehensive literature review of congenital pial AVF will also be included.

CASE DESCRIPTION

A 5-year-old child presented with headache and complex partial seizures. Imaging of the brain revealed the presence of polymicrogyria-pachygyria in the parasagittal frontoparietal lobes with associated underlying white matter hypodensities. Complete agenesis of the corpus callosum was also seen. In addition, enlarged and tortuous vessels were noted along the interhemispheric falx with no appreciable nidus. Bilateral dilated and tortuous ACAs were seen supplying the network of abnormal vessels along the falx. The radiological findings were stable on a follow-up MRI 12 years later.

CONCLUSION

Our reported case adds to current limited knowledge of this rare entity in the pediatric age group, which is traditionally treated aggressively and urgently. Our case demonstrated temporal stability of this lesion with no detrimental complications observed. This suggests that the outcome of pial AVFs with conservative treatment may not be as grim as previously thought.

Intracranial hemorrhage in neonates: A review of etiologies, patterns and predicted clinical outcomes

Intracranial hemorrhage (ICH) in neonates often results in devastating neurodevelopmental outcomes as the neonatal period is a critical window for brain development. The neurodevelopmental outcomes in neonates with ICH are determined by the maturity of the brain, the location and extent of the hemorrhage, the specific underlying etiology and the presence of other concomitant disorders. Neonatal ICH may result from various inherited and acquired disorders. We classify the etiologies of neonatal ICH into eight main categories: (1) Hemorrhagic stroke including large focal hematoma, (2) Prematurity-related hemorrhage, (3) Bleeding diathesis, (4) Genetic causes, (5) Infection, (6) Trauma-related hemorrhage, (7) Tumor-related hemorrhage and (8) Vascular malformations. Illustrative cases showing various imaging patterns that can be helpful to predict clinical outcomes will be highlighted. Potential mimics of ICH in the neonatal period are also reviewed.

Pial fistula in infancy: Report of two cases and literature review with special emphasis on the ruptured group

Cerebral pial fistula is a rare vascular pathology with no more than 150 cases reported. Most cases reported in infancy have been published as case reports. Owing to its high flow, its occurrence in this age group carries the potential risk of heart failure, chronic venous hypertension, seizures and, less frequently, cerebral haemorrhage. We present two cases of pial fistulae in infancy treated by endovascular embolisation using N-butyl cyanoacrylate. A review of the English-language literature was performed for this age group with special emphasis on ruptured cases.

Nongalenic pial arteriovenous fistula: Prenatal diagnosis

Pial arteriovenous (AV) fistulae have rarely been diagnosed in utero. They are characterized by one or more pial arteries flowing directly into a cortical vein without any shunt or interposed capillary bed. In the fetus and the newborn up to 2 years of age, the most common clinical manifestation is heart failure resulting from fistula overload. Later on, hydrocephalus, focal neurologic deficits, headaches, seizures, and cerebral hemorrhage are the most common manifestations. We present a case of nongalenic pial AV fistula diagnosed in the 25th week of pregnancy, which resulted in intrauterine fetal death due to congestive heart failure. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 45:621-625, 2017.

Prenatal Diagnosis and Multimodal Neonatal Treatment of a Rare Pial Arteriovenous Fistula: Case Report and Review of the Literature

BACKGROUND

Intracranial pial arteriovenous fistulas (PAVFs) are direct communications between the arterial and venous system of the brain, with the characteristic absence of a plexiform nidus, as seen in the classic cerebral arteriovenous malformations. These vascular malformations, usually occurring in the pediatric population, very rarely are diagnosed in utero, because of a lack of understanding of the condition and because they may be hard to visualize.

CASE DESCRIPTION

We report a rare case of a mass-effect PAVF diagnosed with fetal magnetic resonance imaging, involving the right cerebral hemisphere, fed by a pericallosal artery and associated with a giant venous dilatation. The PAVF initially was managed by the endovascular embolization. The recruitment of a middle cerebral artery feeder and the rapidly enlarging size of the venous pouch with mass effect required subsequent surgery.

CONCLUSIONS

The 2-stage multimodal treatment resulted in complete disappearance of the PAVF without complications.

Hydrocephalus in a patient with an unruptured pial arteriovenous fistula: hydrodynamic considerations, endovascular treatment, and clinical course

Intracranial pial arteriovenous fistulas, also known as nongalenic fistulas, are rare vascular malformations affecting predominantly the pediatric population. Hydrocephalus is an unusual presentation in which the exact pathophysiology is not fully understood. The aim of treatment in these cases is occlusion of the fistula prior to considering ventricular shunting. Here, the authors describe the hydrodynamic considerations of the paravascular pathway and the resolution of hydrocephalus with endovascular treatment of the fistula.

Intracranial non-galenic pial arteriovenous fistula: A review of the literature

An intracranial non-galenic pial arteriovenous fistula (NGPAVF) is a direct connection between the intracranial artery and vein without a nidus. NGPAVFs are clinically rare, and the current understanding of NGPAVFs is limited. This study searched PubMed for the currently available literature, and a review of the relevant publications revealed that NGPAVFs require aggressive treatment, spontaneous occlusion is uncommon, and the prognosis following conservative treatment is poor. NGPAVFs can be divided into congenital and traumatic (including iatrogenic) types. Clinically, NGPAVFs are characterized by congestive heart failure, epilepsy, hemorrhage, mass effects, and nerve function deficits. For the imaging examination of NGPAVFs, digital subtraction angiography (DSA) is still the gold standard for diagnosis, although magnetic resonance DSA (MRDSA) and 4D computed tomography angiography (CTA) can also provide hemodynamic data in a non-invasive manner. Current treatments for NGPAVFs include surgical resection and endovascular embolization, both of which can yield clinical improvements. However, potential postoperative complications should be addressed, such as fatal bleeding due to rupture and deep vein thrombosis. Some studies recommend postoperative anticoagulation to reduce postoperative thrombotic complications.

Intracranial pial fistulas in pediatric population. Clinical features and treatment modalities

PURPOSE

The purpose of the study is to describe the clinical manifestations and treatment modalities of patients having intracranial pial arteriovenous fistulas (PAVFs).

METHODS

We retrospectively analyzed the cases of PAVFs from January 2004 to December 2013. Medical charts, diagnostic images, surgical, and endovascular reports were reviewed retrospectively during each of the procedures and follow-up. We recorded patient demographics, clinical presentation, treatment modalities, and outcome.

RESULTS

Ten patients with single PAVFs were identified, one of them with multiple holes. The median age was 7.5 years old (20 days to 14 years). Six patients were male (60% of cases). Four PAVFs were localized in the posterior fossa, and six were supratentorial (60%). Two patients had intracranial bleeding, three presented seizures, one was studied for chronic headaches, three manifested by growth retardation, one had hydrocephalus, and one had a congestive heart failure (CHF) and vein of Galen aneurysmal malformation (VGAM). The latter did not improve after embolization and died few days later. Endovascular therapy was used in eight, whereas two patients were surgically managed. Total occlusion of the fistula was achieved in all cases.

CONCLUSIONS

PAVF affects pediatric population at different ages with miscellaneous clinical manifestations. Endovascular treatment is safe and effective when the venous side of the fistula can be occluded.