Rauhalammi Samuli M O, Mangion Kenneth, Barrientos Pauline Hall, Carrick David J A, Clerfond Guillaume, McClure John, McComb Christie, Radjenovic Aleksandra, Berry Colin
BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, UK.
West of Scotland Heart and Lung Centre, Golden Jubilee National Hospital, Glasgow, UK.
J Magn Reson Imaging. 2016 Sep;44(3):541-8. doi: 10.1002/jmri.25217. Epub 2016 Mar 4.
To use magnetic resonance imaging (MRI) at two field strengths to assess healthy adults' regional myocardial noncontrast (native) T1 relaxation time distribution, and global myocardial native T1 between sexes and across age groups.
In all, 84 healthy volunteers underwent MRI at 1.5T and 3.0T. T1 maps were acquired in three left ventricular short axis slices using an optimized modified Look-Locker inversion recovery investigational prototype sequence. T1 measurements in msec were calculated from 16 regions-of-interest, and a global T1 value from all evaluable segments per subject. Associations were assessed with a multivariate linear regression model.
In total, 1297 (96.5%) segments were evaluable at 1.5T and 1263 (94.0%) segments at 3.0T. Native T1 was higher in septal than lateral myocardium (1.5T: 956.3 ± 44.4 vs. 939.2 ± 54.2 msec; P < 0.001; 3.0T: 1158.2 ± 45.9 vs. 1148.9 ± 56.9 msec; P = 0.012). Native T1 decreased with increasing age in females but not in males. Among lowest age tertile (<33 years) global native T1 was higher in females than in males at 1.5T (960.0 ± 20.3 vs. 931.5 ± 22.2 msec, respectively; P = 0.003) and 3.0T (1166.5 ± 19.7 vs. 1130.2 ± 20.6 msec; P < 0.001). No sex differences were observed in upper age tertile (≥55 years) at 1.5T (937.7 ± 25.4 vs. 934.7 ± 22.3 msec; P = 0.762) or 3.0T (1153.0 ± 30.0 vs. 1132.3 ± 23.5 msec; P = 0.056). Association of global native T1 to age (P = 0.002) and sex (P < 0.001) was independent of field strength and body size.
In healthy adults, native T1 values are highest in the ventricular septum. Global native T1 was inversely associated with age in women, but not in men. J. Magn. Reson. Imaging 2016;44:541-548.
使用两种场强的磁共振成像（MRI）评估健康成年人的局部心肌非对比（天然）T1弛豫时间分布，以及不同性别和年龄组的整体心肌天然T1。
总共84名健康志愿者接受了1.5T和3.0T的MRI检查。使用优化的改良Look-Locker反转恢复研究原型序列在三个左心室短轴切片中采集T1图。从16个感兴趣区域计算以毫秒为单位的T1测量值，并计算每个受试者所有可评估节段的整体T1值。使用多元线性回归模型评估相关性。
在1.5T时，总共1297个（96.5%）节段可评估，在3.0T时为1263个（94.0%）节段。天然T1在室间隔比侧壁心肌更高（1.5T：956.3±44.4对939.2±54.2毫秒；P<0.001；3.0T：1158.2±45.9对1148.9±56.9毫秒；P = 0.012）。天然T1在女性中随年龄增加而降低，但在男性中并非如此。在最低年龄三分位数（<33岁）中，1.5T时女性的整体天然T1高于男性（分别为960.0±20.3对931.5±22.2毫秒；P = 0.003），3.0T时也是如此（1166.5±19.7对1130.2±20.6毫秒；P<0.001）。在最高年龄三分位数（≥55岁）中，1.5T（937.7±25.4对934.7±22.3毫秒；P = 0.762）或3.0T（1153.0±30.0对1132.3±23.5毫秒；P = 0.056）时未观察到性别差异。整体天然T1与年龄（P = 0.002）和性别（P<0.001）的关联独立于场强和体型。
在健康成年人中，天然T1值在室间隔最高。女性的整体天然T1与年龄呈负相关，而男性则不然。《磁共振成像杂志》2016年；44：541 - 548。
