Self-gated 23Na-MRI of human lung with separate reconstruction of two respiratory states at 7T

²³Na-MRI at 7T can give valuable insights into lung physiology because ²³Na signals are linked to sodium-potassium-ATPase and to fluid balance. However, low NMR sensitivity and low in-vivo concentrations of Na⁺ ions in-vivo limit the achievable spatial resolution and prolong acquisition times. In this study a retrospective self-gated reconstruction was used to reduce motion artifacts in free-breathing ²³Na-MRI of human lung. The presented method allows for the reconstruction of ²³Na images which correspond to two respiratory motion states for free-breathing volunteers and patients. 3D Dictionary-Learning Compressed-Sensing reconstruction was shown to markedly reduce image noise.