Magnetic resonance T2∗ measurements of the normal human lung in vivo with ultra-short echo times

The objective of this study was to measure T2∗ values of the normal human lung in vivo during breathhold using a rapid gradient-echo sequence with ultra-short echo times (TE). A sagittal slice of the right lung was imaged in six volunteers with various TE ranging from 0.5 ms to 5 ms using a clinical 1.5 Tesla MR scanner. T2∗ values were calculated in a region of interest in the dependent and non-dependent lung. In the dependent lung, T2∗ values of 1.1 ms ± 0.15 ms were measured, and in the non-dependent lung, 0.86 ms ± 0.11 (p < 0.01). T2∗ measurements of the normal human lung during breathhold are feasible with a clinical MR unit. The short T2∗ values require the use of very short TE times (<2.5 ms) in gradient-echo sequences to obtain adequate signal intensity from lung tissue.