MAGNETIZATION-TRANSFER MAGNETIC-RESONANCE-IMAGING OF PARENCHYMAL LUNG-DISEASE

RATIONALE AND OBJECTIVES. Magnetic resonance imaging with magnetizatio n transfer (MT) contrast recently has been described as a method that may provide additional information about the macromolecular compositio n of tissue, Magnetization transfer contrast images were compared to c onventional gradient-recalled echo images in a variety of pulmonary pa renchymal diseases and normal lung. METHODS. Single-slice gradient ech o images were obtained with and without an off-resonance radio frequen cy pulse on a 0.1T MR scanner, The change in signal intensity between identical regions of interest on non-MT and MT images was determined i n 13 patients with known lung disease, five healthy volunteers, and th ree postmortem atelectatic dog lungs. RESULTS. NO significant change i n signal intensity (MT effect) was observed in fat, flowing blood, nor mal lung, atelectatic lung, or in acute pulmonary edema, Chronic paren chymal lung disease showed the greatest MT effect, 37.7% +/- 7.5, Acut e infectious lung disease showed an intermediate degree of MT effect, 19.5% +/- 3.0. CONCLUSIONS. Magnetization transfer contrast magnetic r esonance imaging of pulmonary disease is feasible at low field strengt h and may be useful in the characterization and differentiation of pul monary parenchymal abnormalities, Magnetization transfer contrast appe ars to be proportional to the amount of interstitial fibrosis in lung parenchyma, while acute inflammatory cell infiltration exhibits less M T effect and acute pulmonary edema exhibits very little.