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.