Purpose: To characterize the effect of diffusion time on short-range hyperpolarized 3He MR diffusion measurements across a wide range of emphysema severity. Materials and Methods: 3He diffusion MR imaging was performed on 19 lungs or lobes resected from 18 subjects with varying degrees of emphysema using 3 diffusion times (1.6 msec, 5 msec, and 10 msec) at constant b value. Emphysema severity was quantified as the mean apparent diffusion coefficient (ADC) and as the percentage of pixels with ADC higher than multiple thresholds from 0.30-0.55 cm2/sec (ADC index). Quantitative histology (mean linear intercept) was obtained in 10 of the lung specimens from 10 of the subjects. Results: The mean ADCs with diffusion times of 1.6, 5.0, and 10.0 msec were 0.46, 0.40, and 0.37 cm2/sec, respectively (P
Revised: June 23, 2010 |
Published: September 28, 2009
Citation
Gierada D.S., J.C. Woods, A.J. Bierhals, S.T. Bartel, J.H. Ritter, C.K. Choong, and N.A. Das, et al. 2009.Effects of Diffusion Time on Short-Range Hyperpolarized 3He Diffusivity Measurements in Emphysema.Journal of Magnetic Resonance Imaging 30, no. 4:801-808.PNNL-SA-67338.doi:10.1002/jmri.21912