Department of Biomedical Engineering, University of Southern California, Los Angeles, California, USA.
Ming Hsieh Department of Electrical Engineering, University of Southern California, Los Angeles, California, USA.
Magn Reson Med. 2018 Jul;80(1):272-278. doi: 10.1002/mrm.26994. Epub 2017 Nov 6.
Transit delay is a potential source of error in cardiac arterial spin-labeled (ASL) in heart failure or with collateral circulation. This study demonstrates the feasibility of using transit delay insensitive velocity selective ASL and compares its performance with flow-sensitive alternating inversion recovery (FAIR) ASL.
Velocity selective labeling was achieved using an adiabatic BIR8 preparation. FAIR and velocity-selective ASL (VSASL) with various velocity cutoffs (V = 10-40 cm/s) and labeling directions (anterior-posterior X, lateral-septal Y, and apical-basal Z) were carried out in 10 healthy volunteers (1F/9M age 23-30 y). Myocardial blood flow (MBF) and temporal signal-to-noise (TSNR) were measured.
VSASL sensitivity to perfusion decreased with increasing V . At low V (<5 cm/s), spurious labeling of myocardium occurs and overestimates MBF. MBF measured with FAIR (1.12 ± 0.26 ml/g/min) and VASL (1.26 ± 0.27 ml/g/min) at V of 10 cm/s in Z were comparable (TOST with difference of 0.30 ml/g/min, P = 0.049). TSNR was 2.8 times larger using FAIR (13.62 ± 5.25) than in VSASL (4.87 ± 1.58). VSASL was insensitive to perfusion in the Y direction. X and Z performed similarly with TSNR of 4.17 ± 2.32 and 3.97 ± 0.56, respectively.
VSASL is a promising alternative to FAIR ASL in the heart and is well suited for scenarios when transit delays are long. Magn Reson Med 80:272-278, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
在心力衰竭或存在侧支循环的情况下，传输延迟是心脏动脉自旋标记（ASL）中的一个潜在误差源。本研究旨在展示使用无传输延迟敏感速度选择 ASL 的可行性，并比较其与流动敏感交替反转恢复（FAIR）ASL 的性能。
采用绝热 BIR8 制备实现速度选择标记。在 10 名健康志愿者（1 名女性/9 名男性，年龄 23-30 岁）中进行了 FAIR 和速度选择 ASL（VSASL），各种速度截止值（V=10-40cm/s）和标记方向（前后 X、左右 Y、顶底 Z）。测量心肌血流（MBF）和时间信号到噪声比（TSNR）。
VSASL 对灌注的灵敏度随 V 的增加而降低。在低 V（<5cm/s）下，心肌会出现虚假标记并高估 MBF。在 V 为 10cm/s 时，FAIR（1.12±0.26ml/g/min）和 Z 方向 VSASL（1.26±0.27ml/g/min）测量的 MBF 相当（TOST 差值为 0.30ml/g/min，P=0.049）。FAIR 的 TSNR 比 VSASL（4.87±1.58）大 2.8 倍（13.62±5.25）。VSASL 在 Y 方向对灌注不敏感。X 和 Z 方向的 TSNR 分别为 4.17±2.32 和 3.97±0.56，表现相似。
VSASL 是 FAIR ASL 在心脏中的一种有前途的替代方法，非常适合传输延迟较长的情况。
磁共振医学 80:272-278, 2018。©2017 国际磁共振医学学会。
