Serial Measurement of Superior Vena Cava Flow in Evaluation of the Clinical Severity of Pial Arteriovenous Fistula in an Infant

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.

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.

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.