Assessing potential errors of MRI-based measurements of pulmonary blood flow using a detailed network flow model.
Assessing potential errors of MRI-based measurements of pulmonary blood flow using a detailed network flow model.
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使用详细的网络流量模型评估基于 MRI 的肺血流量测量的潜在误差。
DOI：
10.1152/japplphysiol.00894.2011
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发表时间：
2012
期刊：
影响因子：
--
通讯作者：
Prisk,GK
中科院分区：
文献类型：
--
作者：
Burrowes,KS;Buxton,RB;Prisk,GK
使用动脉自旋标记（ASL）的肺血流的MRI图像测量在一个收缩期射血期间磁性标记的血液到图像平面的递送。然而，该方法潜在地遭受两个问题，每个问题可能取决于成像平面位置：1）反转平面比成像平面厚，导致血液必须穿过以在图像中被检测到的间隙;以及2）ASL包括来自导管血管（动脉和静脉）中的标记血液的信号贡献。通过使用肺循环的计算机模拟模型，我们发现差距将ASL信号降低到矢状面无间隙时的64-74%，冠状面无间隙时的53-84%。导管血管的贡献随图像平面的变化而显著变化，从包含中央肺门血管的图像平面中的总信号的约90%到最大值<20% in peripheral image planes. A threshold cutoff removing voxels with intensities >的35%，导管血管对总ASL信号的贡献平均降低到约20%;然而，具有来自导管血管的大贡献的平面由于高比例的平面内流动而低估了腺泡流动，使得灌注的ASL测量不切实际。在其他图像平面中，灌注占主导地位的ASL图像与ASL和腺泡流之间的良好协议。类似地，通过相对离散度测量的ASL信号的异质性是相同图像平面中腺泡流分布异质性的可靠测量。
MRI images of pulmonary blood flow using arterial spin labeling (ASL) measure the delivery of magnetically tagged blood to an image plane during one systolic ejection period. However, the method potentially suffers from two problems, each of which may depend on the imaging plane location:1) the inversion plane is thicker than the imaging plane, resulting in a gap that blood must cross to be detected in the image; and2) ASL includes signal contributions from tagged blood in conduit vessels (arterial and venous). By using an in silico model of the pulmonary circulation we found the gap reduced the ASL signal to 64–74% of that in the absence of a gap in the sagittal plane and 53–84% in the coronal. The contribution of the conduit vessels varied markedly as a function of image plane ranging from ∼90% of the overall signal in image planes that encompass the central hilar vessels to <20% in peripheral image planes. A threshold cutoff removing voxels with intensities >35% of maximum reduced the conduit vessel contribution to the total ASL signal to ∼20% on average; however, planes with large contributions from conduit vessels underestimate acinar flow due to a high proportion of in-plane flow, making ASL measurements of perfusion impractical. In other image planes, perfusion dominated the resulting ASL images with good agreement between ASL and acinar flow. Similarly, heterogeneity of the ASL signal as measured by relative dispersion is a reliable measure of heterogeneity of the acinar flow distribution in the same image planes.
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影响因子：
3.3
作者：
WEST, JB;DOLLERY, CT
通讯作者：
DOLLERY, CT
DOI：
10.1164/rccm.200406-707oc
发表时间：
2005-01-01
影响因子：
24.7
作者：
Hopkins, SR;Garg, J;Levin, DL
通讯作者：
Levin, DL
影响因子：
3.3
作者：
Tawhai, MH;Hunter, P;Hoffman, EA
通讯作者：
Hoffman, EA
影响因子：
3.3
作者：
WEST, JB;DOLLERY, CT;NAIMARK, A
通讯作者：
NAIMARK, A
影响因子：
4.8
作者：
Hoffman, EA;Reinhardt, JM;McLennan, G
通讯作者：
McLennan, G