Hyperpolarized (129) Xe imaging of the rat lung using spiral IDEAL.
To implement and optimize a single-shot spiral encoding strategy for rapid 2D IDEAL projection imaging of hyperpolarized (Hp) (129) Xe in the gas phase, and in the pulmonary tissue (PT) and red blood cells (RBCs) compartments of the rat lung, respectively.



A theoretical and experimental point spread function analysis was used to optimize the spiral k-space read-out time in a phantom. Hp (129) Xe IDEAL images from five healthy rats were used to: (i) optimize flip angles by a Bloch equation analysis using measured kinetics of gas exchange and (ii) investigate the feasibility of the approach to characterize the exchange of Hp (129) Xe.



A read-out time equal to approximately 1.8 × T2* was found to provide the best trade-off between spatial resolution and signal-to-noise ratio (SNR). Spiral IDEAL approaches that use the entire dissolved phase magnetization should give an SNR improvement of a factor of approximately three compared with Cartesian approaches with similar spatial resolution. The IDEAL strategy allowed imaging of gas, PT, and RBC compartments with sufficient SNR and temporal resolution to permit regional gas exchange measurements in healthy rats.



Single-shot spiral IDEAL imaging of gas, PT and RBC compartments and gas exchange is feasible in rat lung using Hp (129) Xe. Magn Reson Med 76:566-576, 2016. © 2015 Wiley Periodicals, Inc.
Department of Medical Biophysics, Western University, London, ON, Canada.|Imaging Research Laboratories, Robarts Research Institute, London, ON, Canada.
Ozkan
O
Doganay
Department of Medical Biophysics, Western University, London, ON, Canada.|Imaging Research Laboratories, Robarts Research Institute, London, ON, Canada.
Trevor
T
Wade
Imaging Research Laboratories, Robarts Research Institute, London, ON, Canada.
Elaine
E
Hegarty
Department of Medical Biophysics, Western University, London, ON, Canada.|Imaging Research Laboratories, Robarts Research Institute, London, ON, Canada.|Department of Medical Imaging, Western University, London, ON, Canada.
Charles
C
McKenzie
General Electric Global Research, Munich, Germany.
Rolf F
RF
Schulte
Department of Medical Biophysics, Western University, London, ON, Canada.|Imaging Research Laboratories, Robarts Research Institute, London, ON, Canada.|Peter Gilgan Centre for Research and Learning, The Hospital for Sick Children, Toronto, ON, Canada.|Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada.
Giles E
GE
Santyr
D000280:Administration, Inhalation; D000465:Algorithms; D000818:Animals; D003287:Contrast Media / Q000008:administration & dosage / Q000493:pharmacokinetics; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008168:Lung / Q000033:anatomy & histology* / Q000502:physiology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D011659:Pulmonary Gas Exchange / Q000502:physiology*; D019275:Radiopharmaceuticals / Q000008:administration & dosage / Q000493:pharmacokinetics; D051381:Rats; D017207:Rats, Sprague-Dawley; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted; D014979:Xenon Isotopes / Q000008:administration & dosage / Q000493:pharmacokinetics*
D003287:Contrast Media; D019275:Radiopharmaceuticals; D014979:Xenon Isotopes
IDEAL; dissolved xenon; hyperpolarized 129Xe; lung imaging; point spread function; rat; spiral