Improved PCASL imaging of the lung using multiple labeling: Results of an ongoing study

Motivation: We have recently shown that a PCASL-bSSFP sequence provides high quality perfusion images of the lung. However, the perfusion signal is dependent on the respective cardiac cycle. Goal(s): Our aim was to further increase the perfusion signal of the lung parenchyma and/or to shorten the examination time using a new PCASL approach with multiple labeling. Approach: Four volunteers were examined using an ECG-triggered multiple labeling PCASL-bSSFP sequence with different number of labeling pulses, post labeling delays and repetition delays. Results: The PCASL sequence with multiple labeling appears to provide a higher perfusion signal of the lung parenchyma, reducing sensitivity to cardiac cycle variations. Impact: The new PCASL approach with multiple labeling appears to provide a significantly higher perfusion signal of the lung than measurements with single labeling pulse. The sequence makes the PCASL technique more robust and faster for future application in clinical practice.