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Non‐contrast enhanced MR angiography: Established techniques

Until recently, time‐of‐flight (TOF) and phase contrast (PC) were the only non‐contrast MR angiography (NC‐MRA) techniques practically used in clinical. In the decade, NC‐MRA have been gained a revival of an interest among the MR researchers and scientists, in part because of safety concerns related to the possible link between gadolinium‐based contrast agents and nephrogenic systemic fibrosis (NSF). This article introduces other established NC‐MRA techniques, such as ECG‐gated partial Fourier fast spin echo (FSE) and balanced steady‐state free precession (bSSFP), both with and without arterial spin labeling. Then, the article focuses on two main applications: peripheral run‐off and renal MRA. Recently, both applications have achieved remarkable advancements and have become a viable clinical option as an alternative to contrast‐enhanced (CE)‐MRA. In addition, developments on the horizon including whole body MRA applications and further advancement at 3 Tesla are discussed. J. Magn. Reson. Imaging 2012;35:1‐19. © 2011 Wiley Periodicals, Inc.