title: An in vivo NMR imaging determination of multiexponential Hahn T2 of normal lung.
abstract: We describe the first in vivo imaging determination of normal lung tissue's multiexponential transverse magnetization decay. Normal spontaneously breathing rats were used for the measurements. To obtain motion-insensitive images, we used a modified line scan imaging technique which we call the interleaved line scan (ILS). The ILS overcomes the following difficulties associated with imaging lungs: low signal-to-noise ratio (S/N) due to lung's low proton density and short T2 decay, artifacts associated with cardiac and respiratory motion, and excessively long imaging times with conventional line scan techniques. Using the ILS, a 16-line 32-average image with an 8-s repetition time requires 4.3 min. From a series of 16 Hahn spin-echo images with echo times ranging from 16 to 90 ms, we obtained a two-component T2 decay for normal peripheral lung tissue. The measured fast and slow T2 components were 9.5 +/- 1.0 and 34 +/- 5.0 ms for the right lung and 9.0 +/- 1.5 and 32 +/- 4.5 for the left lung. The relative magnetization for the slow T2 component was 7.0 +/- 4.5% for the right lung and 10 +/- 3.0% for the left lung.
authors: Department of Physics, University of Utah, Salt Lake City 84112.
authors: S
authors: S
authors: Shioya
authors: R
authors: R
authors: Christman
authors: D C
authors: DC
authors: Ailion
mesh_terms: D000818:Animals; D005260:Female; D005583:Fourier Analysis; D006321:Heart; D007089:Image Enhancement / Q000379:methods*; D008168:Lung / Q000033:anatomy & histology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009068:Movement; D051381:Rats; D011919:Rats, Inbred Strains; D012119:Respiration; D013909:Thorax