摘要: |
目的:用FAIR序列探讨肺组织膨胀程度对肺灌注的影响,即在不同呼吸相时肺灌注的变化情况。方法:应用GE 1.5T磁共振成像系统,用FAIR序列对10例健康志愿者分别在呼气末和吸气末屏气时进行冠状面扫描。分析在不同呼吸相时反转脉冲标记前/后双肺信号强度变化率(ΔSI%)、肺血流量(PBF)的变化及扫描层面肺面积(Area)的变化情况。结果: (1)不同呼吸相时ΔSI%之间有明显的统计学差异(右肺P=0.021 5,左肺P=0.008 4),呼气末的ΔSI%明显高于吸气末。(2)不同呼吸相时双肺PBF间均有统计学差异(右肺P=8.92×10-5,左肺P=0.000 2),呼气末的PBF明显高于吸气末。(3)不同呼吸相扫描层面的Area间也有明显的统计学差异(右肺P=2.94×10-5,左肺P=0.000 5),吸气末面积明显大于呼气末面积。结论:不同呼吸相时肺灌注间存在差异,在呼气时肺灌注明显高于吸气时,这与呼气时肺容积缩小、血管密度增加有关。 |
关键词: 肺 灌注,局部 动脉自旋标记 磁共振成像 肺膨胀 |
DOI:10.3724/SP.J.1008.2007.01197 |
投稿时间:2007-07-19 |
基金项目:长征医院“三重三优”优秀学科带头人基金(20060109). |
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Influence of lung inflation on arterial spin labeling signal in MR perfusion imaging of human lungs |
FAN Li,LIU Shi-yuan*,XIAO Xiang-sheng,XU Xue-yuan |
(Department of Radiology, Changzheng Hospital, Second Military Medical University, Shanghai 200003, China) |
Abstract: |
Objective:To investigate the influence of lung inflation on MR perfusion imaging of human lung using an arterial spin labeling sequence called flow sensitive alternating inversion recovery (FAIR). Methods: Coronal perfusionweighted images were obtained at different respiratory phases from 10 healthy volunteers on a 1.5T whole body scanner (GE medical system) using FAIR sequence. The changes of tagging efficiency of pulmonary parenchyma (ΔSI %), pulmonary blood flow and area of the scanning slice of different respiratory phases were analyzed. Results: (1) Significant difference was found in ΔSI% between different respiratory phases(right lung P=0.021 5,left lung P=0.008 4), with that at end expiration greater than that at end inspiration. (2) Significant difference was also found in pulmonary blood flow at different respiratory phases (right lung P=8.92×10-5,left lung P=0.000 2), with that at end expiration higher than that at end inspiration. (3) The areas of the scanning slice were also significantly different at different respiratory phases (right lung P=2.94×10-5,left lung P=0.000 5), with that at end inspiration larger than that at end expiration. Conclusion: Pulmonary blood flow during expiration is higher than that during inspiration, which might be due to the decreased lung volume and increased vascular density during expiration. |
Key words: lung perfusion,regional arterial spin labeling magnetic resonance imaging lung inflation |