Fetal and Neonatal MRI Predictors of Aggressive Early Clinical Course in Vein of Galen Malformation

Abstract

BACKGROUND AND PURPOSE: Neonates with vein of Galen malformations are split into 2 cohorts: one needing urgent neonatal embolization, with relatively high mortality and morbidity even with expert care, and a cohort in which embolization can be deferred until infancy, with far better prognosis. We aimed to identify brain MR imaging characteristics obtained from fetal and early neonatal scans that can predict the clinical presentation. MATERIALS AND METHODS:Patients with vein of Galen malformations were stratified into a neonatal at-risk cohort if the patient needed urgent neonatal intervention or if neonatal death occurred; or an infantile treatment cohort if they were stable enough not to require treatment until .1 month of age. Twelve vascular MR imaging parameters, measured by 2 independent observers, were systematically correlated with the need for early neonatal intervention and/or neonatal mortality.RESULTS: A total of 32 neonatal patients (21 patients in the neonatal at-risk cohort, 11 in the infantile treatment cohort) were identified. Maximal mediolateral diameter (area under the curve ¼ 0.866, P , .001) and cross-sectional area (area under the curve ¼ 0.836, P ¼ .002) at the narrowest point of the straight or falcine sinus were most predictive of clinical evolution into the neonatal at-risk cohort. There were 15 patients who had fetal MRIs (10 in the neonatal at-risk cohort and 5 in the infantile treatment cohort). Here too, maximal mediolateral diameter (area under the curve ¼ 0.980, P ¼ .003) and cross-sectional area (area under the curve ¼ 0.941, P ¼ .007) at the narrowest point of the straight or falcine sinus were highly predictive of the neonatal at-risk cohort. CONCLUSIONS:Early neonatal and fetal MR imaging can be readily used for accurate early risk stratification, assisting in directing resources, timing treatment decisions, and identifying appropriate cohorts for novel interventions.

Percutaneous transuterine fetal cerebral embolisation to treat vein of Galen malformations at risk of urgent neonatal decompensation: study protocol for a clinical trial of safety and feasibility

“…For the secondary outcome of efficacy, fetuses with VOGMs measuring>8 mm in the straight sinus or falcine sinus historically have 88% likelihood of requiring neonatal intervention. 14 Using a conservative estimate of 80% requiring such intervention, with a goal of 50% absolute reduction in the need for neonatal intervention to a rate of 30%, the proposed 20-patient cohort would have 80% power to demonstrate statistically significant efficacy of the study intervention.…”

“…A subset analysis suggested that volume over 40 mL may also be at increased risk of late gestational progression. With a larger cohort from the USA and a systematic review of multiple intracranial vascular measurements on fetal MRI, the mediolateral width of the straight or falcine sinus at its point of tightest constriction was found to most robustly correlate with neonatal decompensation necessitating endovascular intervention, more than any other measured vascular parameter, that is, this variable reliably predicted eventual presentation of the fetus in the NAR cohort after delivery 14. This particular parameter is consistent with physiological intuition, as the point of tightest constriction of the venous sinus draining the prosencephalic varix is a definitive limiting point on overall flow return from the malformation to the systemic circulation.…”

“…There have been attempts to define fetal characteristics that may inform a progressive risk of decompensation 12 14. Paladini et al described tricuspid regurgitation as a predictor of brain injury and both tricuspid regurgitation and VOGM varix volume larger than 20 mL as predictors of severe neurological impairment, death or late termination due to severe fetal brain anomalies 12.…”

Vein of Galen Malformation Manifesting as High-Output Heart Failure

“…During weeks 6 to 11 in utero, the median prosencephalic vein is responsible for venous drainage from the developing fetal choroid plexus. As the typical embryological course continues, the vein of Markowski would eventually regress and the internal cerebral veins would take shape and continue drainage of the growing choroid plexus [ 3 ]. However, in the case of the congenital vein of Galen malformation, an arteriovenous shunt develops within the median prosencephalic vein instead.…”

“…Infrequently, during weeks 6-11 of fetal development in utero, an abnormality can occur within the median prosencephalic vein, and an arteriovenous shunt instead arises, which is called the vein of Galen malformation [ 3 ]. The shunt allows for more blood to flow into this vein causing its dilation.…”