The role of Magnetic Resonance Imaging in the Prenatal Diagnosis of Vein of Galen Malformations: A Systematic Review

Abstract

Purpose: Vein of Galen malformations (VOGM) are rare cerebrovascular anomalies present in neonates. Although uncommon, imaging techniques enable its early and prenatal diagnosis. Ultrasonography remains the standard screening method, but the impact of magnetic resonance imaging (MRI) is yet to be fully elucidated. This study aims to systematically review literature to clarify the relevance of MRI in assessing VOGM in fetuses and highlight the need for formal MRI protocols to guide clinicians. Methods: A retrospective analysis was performed across three databases (Medline, Scopus, Web of Science), until December 2023. Articles were selected based on inclusion and exclusion criteria, with fetal brain abnormalities indicative of VOGM on MRI scans as the primary outcome. Results: After screening, 22 articles were eligible (19 case reports and series, 2 retrospective cohort studies and 1 narrative review), involving 160 fetuses. The prevailing MRI techniques were 1.5T T2-weighted imaging HASTE sequence, and Diffusion-weighted imaging. Only 36% of studies included Magnetic Resonance Angiography (MRA). Maternal aspects varied, while gestational age was predominantly after 30 weeks. MRI findings complemented and confirmed ultrasound results, and follow-up data was limited due to diverse neonatal outcomes. Conclusion: MRI is indispensable for the prenatal approach of VOGM, describing the anomaly itself and relevant sequalae, significantly influencing clinical decision-making specially in terms of treatment choice and prognosis determination. The heterogeneity of the chosen MRI sequences hindered the comparison of results, reflecting the need for standardized MRI protocols and warranting further research for consensus in this area.