Fan Li, Liu Shi-yuan, Sun Fei, Xiao Xiang-sheng
Department of Radiology, ChangZheng Hospital Affiliated to Second Military Medical University, No. 415 Fengyang Road, Shanghai 200003, China.
Eur J Radiol. 2009 Apr;70(1):41-8. doi: 10.1016/j.ejrad.2007.12.013. Epub 2008 Feb 5.
The aim of this study was to assess pulmonary parenchyma perfusion with flow-sensitive alternating inversion recovery (FAIR) in comparison with 3D dynamic contrast-enhanced (DCE) imaging in healthy volunteers and in patients with pulmonary embolism or lung cancer.
Sixteen healthy volunteers and 16 patients with pulmonary embolism (5 cases) or lung cancer (11 cases) were included in this study. Firstly, the optimized inversion time of FAIR (TI) was determined in 12 healthy volunteers. Then, FAIR imaging with the optimized TI was performed followed by DCE-MRI on the other 4 healthy volunteers and 16 patients. Tagging efficiency of lung and SNR of perfusion images were calculated with different TI values. In the comparison of FAIR with DCE-MRI, the homogeneity of FAIR and DCE-MRI perfusion was assessed. In the cases of perfusion abnormality, the contrast between normal lung and perfusion defects was quantified by calculating a normalized signal intensity ratio.
One thousand milliseconds was the optimal TI, which generated the highest lung tagging efficiency and second highest PBF SNR. In the volunteers, the signal intensity of perfusion images acquired with both FAIR and DCE-MRI was homogeneous. Wedged-shaped or triangle perfusion defects were visualized in five pulmonary embolisms and three lung cancer cases. There was no significant statistical difference in signal intensity ratio between FAIR and DCE-MRI (P>0.05). In the rest of eight lung cancers, all the lesions showed low perfusion against the higher perfused pulmonary parenchyma in both FAIR and DCE-MRI.
Pulmonary parenchyma perfusion imaging with FAIR was feasible, consistent and could obtain similar functional information to that from DCE-MRI.
本研究旨在比较流动敏感交替反转恢复（FAIR）序列与三维动态对比增强（DCE）成像技术对健康志愿者、肺栓塞患者及肺癌患者肺实质灌注情况的评估。
本研究纳入了16名健康志愿者以及16例患有肺栓塞（5例）或肺癌（11例）的患者。首先，在12名健康志愿者中确定FAIR序列的最佳反转时间（TI）。然后，对另外4名健康志愿者和16例患者进行了最佳TI值的FAIR成像，随后进行DCE-MRI检查。计算不同TI值下肺的标记效率和灌注图像的信噪比。在FAIR与DCE-MRI的比较中，评估了FAIR和DCE-MRI灌注的均匀性。对于灌注异常的病例，通过计算归一化信号强度比来量化正常肺组织与灌注缺损之间的对比度。
1000毫秒是最佳TI，此时肺标记效率最高，肺灌注血流（PBF）信噪比次之。在志愿者中，FAIR和DCE-MRI获取的灌注图像信号强度均匀。在5例肺栓塞和3例肺癌病例中可见楔形或三角形灌注缺损。FAIR与DCE-MRI之间的信号强度比无显著统计学差异（P>0.05）。在其余8例肺癌中，FAIR和DCE-MRI均显示所有病变相对于灌注较高的肺实质呈低灌注。
FAIR序列用于肺实质灌注成像可行、结果一致，且能获得与DCE-MRI相似的功能信息。
