Whole lung morphometry with 3D multiple b-value hyperpolarized gas MRI and compressed sensing.
To demonstrate three-dimensional (3D) multiple b-value diffusion-weighted (DW) MRI of hyperpolarized3He gas for whole lung morphometry with compressed sensing (CS).



A fully-sampled, two b-value, 3D hyperpolarized3He DW-MRI dataset was acquired from the lungs of a healthy volunteer and retrospectively undersampled in the kyand kzphase-encoding directions for CS simulations. Optimal k-space undersampling patterns were determined by minimizing the mean absolute error between reconstructed and fully-sampled3He apparent diffusion coefficient (ADC) maps. Prospective three-fold, undersampled, 3D multiple b-value3He DW-MRI datasets were acquired from five healthy volunteers and one chronic obstructive pulmonary disease (COPD) patient, and the mean values of maps of ADC and mean alveolar dimension (LmD) were validated against two-dimensional (2D) and 3D fully-sampled3He DW-MRI experiments.



Reconstructed undersampled datasets showed no visual artifacts and good preservation of the main image features and quantitative information. A good agreement between fully-sampled and prospective undersampled datasets was found, with a mean difference of +3.4% and +5.1% observed in mean global ADC and LmDvalues, respectively. These differences were within the standard deviation range and consistent with values reported from healthy and COPD lungs.



Accelerated CS acquisition has facilitated 3D multiple b-value3He DW-MRI scans in a single breath-hold, enabling whole lung morphometry mapping. Magn Reson Med 77:1916-1925, 2017. © 2016 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
POLARIS, Academic Unit of Radiology, University of Sheffield, United Kingdom.
Ho-Fung
HF
Chan
POLARIS, Academic Unit of Radiology, University of Sheffield, United Kingdom.
Neil J
NJ
Stewart
POLARIS, Academic Unit of Radiology, University of Sheffield, United Kingdom.
Juan
J
Parra-Robles
POLARIS, Academic Unit of Radiology, University of Sheffield, United Kingdom.
Guilhem J
GJ
Collier
POLARIS, Academic Unit of Radiology, University of Sheffield, United Kingdom.|Insigneo, Institute for in silico medicine, Sheffield, United Kingdom.
Jim M
JM
Wild
D000328:Adult; D000465:Algorithms; D003198:Computer Simulation; D044962:Data Compression; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005740:Gases; D064368:Healthy Volunteers; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008168:Lung / Q000000981:diagnostic imaging*; D008297:Male; D015233:Models, Statistical; D011650:Pulmonary Alveoli / Q000000981:diagnostic imaging; D029424:Pulmonary Disease, Chronic Obstructive / Q000000981:diagnostic imaging*; D012189:Retrospective Studies
D005740:Gases
ADC mapping; compressed sensing; hyperpolarized 3He; lung morphometry; stretched exponential model