Abstract:
PURPOSE:Fourier decomposition (FD) is a noninvasive method for assessing ventilation and perfusion-related information in the lungs. However, the technique has a low signal-to-noise ratio (SNR) in the lung parenchyma. We present an approach to increase the SNR in both morphological and functional images. METHODS:The data used to create functional FD images are usually acquired using a standard balanced steady-state free precession (bSSFP) sequence. In the standard sequence, the possible range of the flip angle is restricted due to specific absorption rate (SAR) limitations. Thus, using a variable flip angle approach as an optimization is possible. This was validated using measurements from a phantom and six healthy volunteers. RESULTS:The SNR in both the morphological and functional FD images was increased by 32%, while the SAR restrictions were kept unchanged. Furthermore, due to the higher SNR, the effective resolution of the functional images was increased visibly. The variable flip angle approach did not introduce any new transient artifacts, and blurring artifacts were minimized. CONCLUSION:Both a gain in SNR and an effective resolution gain in functional lung images can be obtained using the FD method in conjunction with a variable flip angle optimized bSSFP sequence.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Corteville DM,Kjïrstad Å,Henzler T,Zöllner FG,Schad LRdoi
10.1002/mrm.25293subject
Has Abstractpub_date
2015-05-01 00:00:00pages
1999-2004issue
5eissn
0740-3194issn
1522-2594journal_volume
73pub_type
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