Influence of proton T1 on oxymetry using Overhauser enhanced magnetic resonance imaging.
Influence of proton T1 on oxymetry using Overhauser enhanced magnetic resonance imaging.
复制标题
使用 Overhauser 增强磁共振成像质子 T1 对血氧测定的影响。
DOI：
10.1002/mrm.20564
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发表时间：
2005
期刊：
影响因子：
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通讯作者：
Krishna,MuraliC
中科院分区：
文献类型：
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作者：
Matsumoto,Shingo;Utsumi,Hideo;Aravalluvan,Thirumaran;Matsumoto,Ken-Ichiro;Matsumoto,Atsuko;Devasahayam,Nallathamby;Sowers,AnastasiaL;Mitchell,JamesB;Subramanian,Sankaran;Krishna,MuraliC
在Overhauser增强磁共振成像（OMRI）体内测量氧分压（pO2）中，引入顺磁造影剂，通过动态核极化增强质子信号。在使用OMRI计算po2时，通常假设整个感兴趣的区域有一个均匀的质子t1。这里，通过幻影和体内（小鼠）成像证明，这种假设可能导致po2的错误估计。由于OMRI的Zeeman场非常低（15-20 mT），因此较差的原生MR强度阻碍了对像素智慧et1的直接估计。为了避免这个问题，描述了一种使用OMRI扫描仪对质子t1进行逐像素映射的简单方法。通过小鼠SCC肿瘤中心切片的质子t1图像清楚地显示t1分布范围（0.2 ~ 1.6 s）。使用像素智能et1值计算po2图像有望通过OMRI进行最小伪影的血氧测量。中华医学杂志，2005,34(4):513 - 517。出版于2005年Wiley‐Liss， Inc。
In Overhauser enhanced magnetic resonance imaging (OMRI) for in vivo measurement of oxygen partial pressure (pO2), a paramagnetic contrast agent is introduced to enhance the proton signal through dynamic nuclear polarization. A uniform protonT1is generally assumed for the entire region of interest for the computation ofpO2using OMRI. It is demonstrated here, by both phantom and in vivo (mice) imaging, that such an assumption may cause erroneous estimate ofpO2. A direct estimate of pixel‐wiseT1is hampered by the poor native MR intensities, owing to the very low Zeeman field (15–20 mT) in OMRI. To circumvent this problem, a simple method for the pixel‐wise mapping of protonT1using the OMRI scanner is described. A protonT1image of a slice through the center of an SCC tumor in a mouse clearly shows a range ofT1distribution (0.2∼1.6 s). Computation ofpO2images using pixel‐wiseT1values promises oximetry with minimal artifacts by OMRI. Magn Reson Med 54:213–217, 2005. Published 2005 Wiley‐Liss, Inc.