Comparing vascular morphology and hemodynamics in patients with vein of Galen malformations using intracranial 4D flow MRI.

Abstract

Vein of Galen malformation (VOGM) is the most common congenital cerebrovascular malformation, and many patients suffer high mortality rates and poor cognitive outcomes. Quantitative diagnostic tools are needed to improve clinical outcomes. A prospective study of children with VOGM was conducted by acquiring 4D flow MRI to quantify total blood inflow to the brain, flow in the pathologic falcine sinus, and flow in the superior sagittal sinus. Linear regression was used to test the relationships between these flows and age, clinical status, and the mediolateral diameter of the lesion's outflow tract through the falcine or straight sinus (MD), which is a known morphological prognostic metric. In all 11 subjects (mean age 22±17 weeks [SD]), total blood flow to the brain always exceeded normal levels (1063±403 ml/min [mean±SD]). Significant correlations were observed between falcine sinus flow and MD, the posterior/middle cerebral artery flow ratio and age at scan, and between superior sagittal sinus flow proximal to malformation inflow and age at scan. Using 4D flow MRI we established the hemodynamic underpinnings of MD, and investigated metrics representing parenchymal venous drainage that could be used to monitor the normalization of hemodynamics during embolization therapy. ACA = anterior cerebral artery; BA = basilar artery; MD = falcine or straight sinus mediolateral diameter; NAR = neonatal at risk; PCA = posterior cerebral artery; PCom = posterior communicating artery; SSS = superior sagittal sinus; VOGM = vein of Galen malformation.