Maximum intensity projection (MIP) is a commonly used tool to measure luminal stenosis. MIP images may underestimate stenosis. Directly measuring lumen size represents an alternative solution, but manual segmentation is laborious and sensitive to flow artifacts and bias. Simultaneous non-contrast angiography and intraplaque hemorrhage (SNAP) imaging affords a novel 3D non-contrast MRA approach. The polarity map available with SNAP makes it less sensitive to flow artifacts and facilitates objective lumen boundary definition. In this study, objective lumen measurements on SNAP and 3D-TOF are compared using CE-MRA as a reference. Results showed good agreement between SNAP and CE-MRA on lumen assessment.