Scholz T D, Martins J B, Skorton D J
Cardiovascular Center, University of Iowa, Iowa City 52242.
Magn Reson Med. 1992 Jan;23(1):89-95. doi: 10.1002/mrm.1910230110.
Tissue changes known to occur with acute myocardial infarction include increases in tissue water and lipid content. We sought to evaluate the relative contribution of alterations in tissue water and fat content to the changes of T1 and T2 relaxation times with infarction. Nine mongrel dogs underwent coronary artery occlusion for 6-12 h. T1 and T2 at 20 MHz and tissue water and fat content of normal and infarcted tissue were measured. Tissue water content, T1, and T2 were significantly greater in infarcted myocardium compared to normal (P less than 0.05). Tissue fat content, while not significantly different, increased linearly in infarcted samples as a function of duration of ischemia (r = 0.77). Despite this increase in fat content, only tissue water content was significantly linearly related to T1 (r = 0.97) and T2 (r = 0.91). Increases in T1 and T2 of infarcted tissue appeared to be most significantly influenced by changes in tissue water content. While total tissue fat content increased with duration of ischemia, it did not appear to significantly alter T1 or T2.
已知急性心肌梗死时发生的组织变化包括组织水分和脂质含量增加。我们试图评估组织水分和脂肪含量的改变对梗死时T1和T2弛豫时间变化的相对贡献。9只杂种犬冠状动脉闭塞6 - 12小时。测量了正常和梗死组织在20MHz时的T1和T2以及组织水分和脂肪含量。与正常心肌相比，梗死心肌的组织水分含量、T1和T2显著更高（P<0.05）。梗死样本中的组织脂肪含量虽然无显著差异，但随缺血持续时间呈线性增加（r = 0.77）。尽管脂肪含量增加，但只有组织水分含量与T1（r = 0.97）和T2（r = 0.91）显著线性相关。梗死组织T1和T2的增加似乎最受组织水分含量变化的显著影响。虽然总组织脂肪含量随缺血持续时间增加，但似乎并未显著改变T1或T2。
