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T1‐insensitive flow suppression using quadruple inversion‐recovery

A new flow suppression method has been proposed for the acquisition of blood‐suppressed (black‐blood) images in combination with administration of a positive contrast agent. The technique employs the quadruple inversion‐recovery (QIR) preparative pulse sequence, which consists of two double‐inversion modules followed by two delays. Within each double inversion, a nonselective RF pulse is immediately followed by a slice‐selective one. The time intervals of the sequence can be calculated using an algorithm based on minimization of the variation of a signal equation over an entire range of T1 occurring in blood before and after contrast administration. QIR is highly insensitive to variations of T1, providing efficient suppression of a flow signal with T1 in a range of 200–1200 ms. The technique utilizes identical scan parameters for pre‐ and postcontrast acquisition, and thus allows reliable quantitative interpretation of contrast enhancement (CE). The clinical application of QIR was demonstrated in high‐resolution, contrast‐enhanced, black‐blood imaging of atherosclerotic plzzaque. Magn Reson Med 48:899–905, 2002. © 2002 Wiley‐Liss, Inc.