Estimation and visualization of regional and global pulmonary perfusion with 3D magnetic resonance angiography

The purposes of this work were to estimate regional and global pulmonary perfusion and display pulmonary vasculature in 10 postoperative lung transplant patients using breath-hold, contrast-enhanced (0.2 mmol/kg, Gd DTPA-BMA, Omniscan, Nycomed, Inc., Princeton, NJ), three-dimensional (3D) magnetic resonance angiography (MRA) with specially designed double-variable-angle uniform signal excitation (VUSE) radio frequency (RF) pulses. Double-VUSE scans imaged both lungs simultaneously during contrast agent injection and provided both qualitative and quantitative information about pulmonary perfusion. Double-VUSE pulses clearly displayed healthy and diseased vessels. There was a strong correlation between contrast-enhanced double-VUSE MRA flow estimates and those measured from nuclear scans for global or whole lung (R(2) = 0.95; P = 0.000002) and upper, central, and lower thirds of the lung (R(2) = 0.89, 0.92, and 0.86, respectively; P < 0.001 for each region). In conclusion, 3D MRA using VUSE pulses in combination with a contrast agent is a valuable tool for the assessment of pulmonary perfusion that simultaneously acquires data for both the qualitative display of pulmonary vessels and the quantification of regional and global differential pulmonary blood flow.