MR Quantification of Flow in Children with Vascular Malformations

The evaluation of treatments such as embolization, stereotactic radiation, and even surgery would be enhanced by an objective method of measuring flow in feeding arteries or draining veins. We developed a non-invasive method of measuring vascular flow using cardiac gated phase contrast MR angiography (MR Q flow). The purpose of this work was to employ the same technique in a series of patients with vascular malformations of the head and neck. We selected a series of vascular malformations with simple arterial and venous architecture and significantly smaller vessel diameters than that encountered with Vein of Calen Malformations. Our aim was to determine the reproducibility of the derived flow values by using multiple velocity encoded sequences (VENC) and compare the values derived from the arterial feeders to the venous outflow data. There are inherent technical difficulties with assessing flow through multiple arterial feeders or draining veins, so the technique is most easily applied to AVMs with simple, easily defined feeding arteries or draining veins. Nonetheless, this technique is relatively straightforward to learn, rapid, cost-effective and may provide an objective means to assess therapeutic maneuvers when applied to head and neck vascular malformations.