Bauman Grzegorz, Pusterla Orso, Bieri Oliver
Division of Radiological Physics, Department of Radiology, University of Basel Hospital, Basel, Switzerland.
Magn Reson Med. 2016 Apr;75(4):1647-53. doi: 10.1002/mrm.25697. Epub 2015 May 12.
To assess whether ultra-fast steady-state free precession (ufSSFP) can improve image quality in Fourier decomposition (FD) MRI of lung ventilation and perfusion.
Series of two-dimensional time-resolved lung images were acquired in healthy volunteers at 1.5 Tesla (T) and 3T using an FD adapted ufSSFP. For comparison, the imaging protocol was complemented by a standard implementation of the FD MRI technique using balanced steady-state free precession (bSSFP). Imaging parameters were evaluated to optimize the ufSSFP FD MRI protocol with respect to the signal intensity of the lung parenchyma and the severity of image artifacts.
FD MRI with the adapted ufSSFP pulse sequence resulted in increased signal intensity in the lung tissue by 19% and significantly decreased banding artifacts due to shorter repetition times: 1.46 ms for ufSSFP and 1.90 ms for bSSFP. Despite improved image quality FD MRI is still problematic at 3T.
MRI of the lung with ufSSFP performs better than bSSFP in terms of signal and banding artifacts, and can be used to either increase resolution or overall image quality of FD images.
评估超快速稳态自由进动（ufSSFP）是否能改善肺部通气和灌注的傅里叶分解（FD）磁共振成像（MRI）中的图像质量。
在1.5特斯拉（T）和3T条件下，使用适配FD的ufSSFP对健康志愿者采集一系列二维时间分辨肺部图像。为作比较，成像方案还补充了使用平衡稳态自由进动（bSSFP）的FD MRI技术的标准实施。评估成像参数，以根据肺实质的信号强度和图像伪影的严重程度优化ufSSFP FD MRI方案。
采用适配的ufSSFP脉冲序列的FD MRI使肺组织中的信号强度增加了19%，并且由于重复时间更短，带状伪影显著减少：ufSSFP为1.46毫秒，bSSFP为1.90毫秒。尽管图像质量有所改善，但FD MRI在3T时仍存在问题。
就信号和带状伪影而言，采用ufSSFP的肺部MRI比bSSFP表现更好，并且可用于提高FD图像的分辨率或整体图像质量。
