Subject-specific Dose of Ferumoxytol for Vascular Suppression in Brachial Plexus Magnetic Resonance Neurography

Motivation: Ferumoxytol effectively suppresses vasculature in MR neurography, but the optimal dose is unknown. Goal(s): To determine the optimal dose by weight and blood volume. Approach: Thirty-two subjects were infused with varying Ferumoxytol doses (30 to 255 mg Fe) and underwent MR neurography at 3-Tesla; the vessel-to-muscle contrast ratio (CR) was measured. Results: Logarithmic regression improved with weight-based and volume-based doses (R²=0.443 to 0.613) versus the absolute dose (R²=0.362 to 0.499). 1.75-1.92 mg Fe/kg or 26.9-29.5 mg Fe/L doses were required to obtain CR<0.2, demonstrating that the subject weight/blood volume should be considered to optimize Ferumoxytol-based vascular suppression. Impact: Subject weight- or blood-volume-specific Ferumoxytol doses may provide effective vascular suppression for MR neurography evaluation of peripheral neuropathies like Parsonage Turner Syndrome (PTS), to reduce the dose and infusion time required.