Imaging pulmonary blood flow and perfusion using phase-sensitive selectiveinversion recovery

A technique is described for imaging pulmonary blood flow using a phase-sen sitive selective inversion recovery (PS-SIR) sequence. PS-SIR image reconst ruction provides excellent contrast, differentiating fully relaxed inflowin g blood from inverted blood and lung tissue. The magnetization of the inver ted tissues remains negative at any inversion delay less than that at which the magnetization of the lung tissue is nulled, whereas that of the fully relaxed inflowing blood is always positive. Pulmonary blood flow can be obs erved by tracking the propagation of the pixels with positive values. Five healthy volunteers were imaged. The normal pattern of blood flow advancing from the central arteries toward the peripheries and into the lung parenchy ma with return toward the center via draining veins was depicted. The metho d offers promise for evaluating pulmonary blood flow without the need for i mage subtraction or contrast administration. Magn Reson Med 43:793-795, 200 0. (C) 2000 Wiley-Liss, Inc.