[Study of pulmonary parenchyma MRI with flow sensitive alternating inversion recovery]

To evaluate the feasibility of pulmonary parenchyma perfusion imaging with flow sensitive alternating inversion recovery (FAIR), which is noninvasive and doesn't necessitate injection of contrast agents.

A total of 20 healthy volunteers were undergone SSFSE-FAIR imaging. Two coronal perfusion-weighted MR images were acquired, one being the posterior coronal slice, and the other being the middle slice parallel to the right pulmonary artery. The relative pulmonary blood flow (rPBF) values of bilateral lungs were calculated respectively and right to left rPBF ratio (R/L) was also evaluated.

(1) The rPBF of the right lung in the posterior coronal slice was 87 +/- 24, not significantly different from that of the left lung (87 +/- 27, P > 0.05) with the R/L of 1.01 +/- 0.04. However, the rPBF of the right lung in the middle coronal slice was 41 +/- 15, significantly lower than that of the left lung (74 +/- 25, P < 0.05) with the R/L of 0.55 +/- 0.05. (2) There were significant differences in the rPBF of the homolateral lung on different slices (both P < 0.05). The rPBF values on the posterior slice of the right and left lungs were both significantly higher than those on the middle slice.

Pulmonary perfusion with FAIR is feasible, but the perfusion of right and left lung may be different on certain slice due to spin saturation effect. FAIR is also sensitive to reflect perfusion heterogeneity due to gravity effect.