Nguyễn Thu Phương

We studied the time course of changes in the Hahn spin-echo decay (Hahn-T2 ) in lungs of spontaneously breath-ing living rats at 1 hour, 3 hours, and 7 days following oleic acid injection. Motion artifacts were minimized by using the motion-insensitive interleaved rapid line scan (ILS) imaging technique. Prior to injury, the lungs exhib-ited two resolvable exponential Hahn-T2 components. One and 3 hours after injury the decay showed a region-ally nonuniform behavior, which was fit with one, two, or three exponential components. The short and medium components increased at 1 and 3 hours after injection. The third, much longer, component is probably due to intraalveolar pulmonary edema. After 7 days the Hahn decay was similar to that observed before injury, proba-bly reflecting resolution of the edema. Our data suggest that Hahn-T2measurements can be used to characterize the time course and regional distribution of lung injury in living animals. J. Magn. Reson. Imaging 2000;11: 215–222....