In vivo measurement of T*2 and field inhomogeneity maps in the human heart at 1.5 T
In vivo measurement of T*2 and field inhomogeneity maps in the human heart at 1.5 T
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DOI：
10.1002/mrm.1910390617
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发表时间：
1998-06-01
影响因子：
3.3
通讯作者：
McVeigh, ER
中科院分区：
文献类型：
--
作者：
Reeder, SB;Faranesh, AZ;McVeigh, ER
心脏回波平面成像总是受到心肌中严重失真和T*（2）衰减区域的影响。这项工作的目的是进行局部测量的T*（2）和外地不均匀性的心肌，并确定源的局灶性信号损失和失真。测量5名正常志愿者从基底到心尖的短轴切片的场不均匀性图和T*（2）。结果发现，T*（2）范围为26 ms（SD = 7 ms，n = 5）至41 ms（SD = 11 ms，n = 5）在大部分的心脏，峰-峰场不均匀性差为71 Hz（SD = 14 Hz，n = 5）。在所有心脏中，严重信号丢失区域始终邻近左心室后静脉;这些区域的T*（2）为12 ms（SD = 2 ms，n = 5），与周围心肌的共振频率差异为70-100 Hz。这些效应可能是由这些静脉中缺氧血液的磁化率增加引起的。
Cardiac echo-planar imaging suffers invariably from regions of severe distortion and T*(2) decay in the myocardium. The purpose of this work was to perform local measurements of T*(2) and field inhomogeneities in the myocardium and to identify the sources of focal signal loss and distortion. Field inhomogeneity maps and T*(2) were measured in five normal volunteers in short-axis slices spanning from base to apex. It was found that T*(2) ranged from 26 ms (SD = 7 ms, n = 5) to 41 ms (SD = 11 ms, n = 5) over most of the heart, and peak-to-peak field inhomogeneity differences were 71 Hz (SD = 14 Hz, n = 5). In all hearts, regions of severe signal loss were consistently adjacent to the posterior vein of the left ventricle; T*(2) in these regions was 12 ms (SD = 2 ms, n = 5), and the difference in resonance frequency with the surrounding myocardium was 70-100 Hz. These effects may be caused by increased magnetic susceptibility from deoxygenated blood in these veins.