|| Checking for direct PDF access through Ovid
To develop and validate a method for acquiring helium-3 (3He) and proton (1H) three-dimensional (3D) image sets of the human lung with isotropic spatial resolution within a 10-s breath-hold by using compressed sensing (CS) acceleration, and to assess the fidelity of undersampled images compared with fully sampled images.The undersampling scheme for CS acceleration was optimized and tested using 3He ventilation data. Rapid 3D acquisition of both 3He and 1H data during one breath-hold was then implemented, based on a balanced steady-state free-precession pulse sequence, by random undersampling of k-space with reconstruction by means of minimizing the L1 norm and total variance. CS-reconstruction fidelity was evaluated quantitatively by comparing fully sampled and retrospectively undersampled image sets.Helium-3 and 1H 3D image sets of the lung with isotropic 3.9-mm resolution were acquired during a single breath-hold in 12 s and 8 s using acceleration factors of 2 and 3, respectively. Comparison of fully sampled and retrospectively undersampled 3He and 1H images yielded mean absolute errors <10% and structural similarity indices >0.9.By randomly undersampling k-space and using CS reconstruction, high-quality 3He and 1H 3D image sets with isotropic 3.9-mm resolution can be acquired within an 8-s breath-hold. Magn Reson Med 74:1110–1115, 2015. © 2014 Wiley Periodicals, Inc.