Akçakaya Mehmet, Weingärtner Sebastian, Basha Tamer A, Roujol Sébastien, Bellm Steven, Nezafat Reza
Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, Minnesota, USA.
Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, Minnesota, USA.
Magn Reson Med. 2016 Sep;76(3):888-96. doi: 10.1002/mrm.25975. Epub 2015 Sep 29.
To develop a heart-rate independent breath-held joint T1 -T2 mapping sequence for accurate simultaneous estimation of coregistered myocardial T1 and T2 maps.
A novel preparation scheme combining both a saturation pulse and T2 -preparation in a single R-R interval is introduced. The time between these two pulses, as well as the duration of the T2 -preparation is varied in each heartbeat, acquiring images with different T1 and T2 weightings, and no magnetization dependence on previous images. Inherently coregistered T1 and T2 maps are calculated from these images. Phantom imaging is performed to compare the proposed maps with spin echo references. In vivo imaging is performed in ten subjects, comparing the accuracy and precision of the proposed technique to existing myocardial T1 and T2 mapping sequences of the same duration.
Phantom experiments show that the proposed technique provides accurate quantification of T1 and T2 values over a wide-range (T1 : 260 ms to 1460 ms, T2 : 40 ms to 200 ms). In vivo imaging shows that the proposed sequence quantifies T1 and T2 values similar to a saturation-based T1 mapping and a conventional breath-hold T2 mapping sequence, respectively.
The proposed sequence allows joint estimation of accurate and coregistered quantitative myocardial T1 and T2 maps in a single breath-hold. Magn Reson Med 76:888-896, 2016. © 2015 Wiley Periodicals, Inc.
开发一种与心率无关的屏气联合T1 - T2映射序列,用于准确同时估计配准的心肌T1和T2图谱。
引入一种新颖的准备方案,在单个R - R间期内结合饱和脉冲和T2准备。这两个脉冲之间的时间以及T2准备的持续时间在每个心跳中变化,获取具有不同T1和T2权重的图像,且磁化不依赖于先前的图像。从这些图像中计算出固有的配准T1和T2图谱。进行体模成像以将所提出的图谱与自旋回波参考进行比较。对十名受试者进行体内成像,将所提出技术的准确性和精确性与相同持续时间的现有心肌T1和T2映射序列进行比较。
体模实验表明,所提出的技术在宽范围内(T1:260毫秒至1460毫秒,T2:40毫秒至200毫秒)提供了准确的T1和T2值定量。体内成像表明,所提出的序列分别定量T1和T2值,类似于基于饱和的T1映射和传统的屏气T2映射序列。
所提出的序列允许在单次屏气中联合估计准确且配准的定量心肌T1和T2图谱。《磁共振医学》76:888 - 896, 2016。© 2015威利期刊公司。