New York University Langone Medical Center, New York, NY 10016, USA.
J Magn Reson Imaging. 2011 Sep;34(3):676-84. doi: 10.1002/jmri.22647. Epub 2011 Jul 14.
To develop, and validate in vivo, a robust quantitative first-pass perfusion cardiovascular MR (CMR) method with accurate arterial input function (AIF) and myocardial wall enhancement.
A saturation-recovery (SR) pulse sequence was modified to sequentially acquire multiple slices after a single nonselective saturation pulse at 3 Tesla. In each heartbeat, an AIF image is acquired in the aortic root with a short time delay (TD) (50 ms), followed by the acquisition of myocardial images with longer TD values (∼150-400 ms). Longitudinal relaxation rates (R(1) = 1/T(1)) were calculated using an ideal saturation recovery equation based on the Bloch equation, and corresponding gadolinium contrast concentrations were calculated assuming fast water exchange condition. The proposed method was validated against a reference multi-point SR method by comparing their respective R(1) measurements in the blood and left ventricular myocardium, before and at multiple time-points following contrast injections, in 7 volunteers.
R(1) measurements with the proposed method and reference multi-point method were strongly correlated (r > 0.88, P < 10(-5)) and in good agreement (mean difference ±1.96 standard deviation 0.131 ± 0.317/0.018 ± 0.140 s(-1) for blood/myocardium, respectively).
The proposed quantitative first-pass perfusion CMR method measured accurate R(1) values for quantification of AIF and myocardial wall contrast agent concentrations in 3 cardiac short-axis slices, in a total acquisition time of 523 ms per heartbeat.
开发并验证一种稳健的定量首过灌注心血管磁共振（CMR）方法，该方法具有准确的动脉输入函数（AIF）和心肌壁增强。
在 3T 下，对饱和恢复（SR）脉冲序列进行了修改，以便在单次非选择性饱和脉冲后顺序采集多个切片。在每个心跳中，通过短时间延迟（TD）（50ms）在主动脉根部采集 AIF 图像，然后使用较长的 TD 值（约 150-400ms）采集心肌图像。根据 Bloch 方程，使用理想的饱和恢复方程计算纵向弛豫率（R(1)=1/T(1)），并假设快速水交换条件计算相应的钆对比浓度。该方法在 7 名志愿者中进行了验证，通过比较两种方法在注射对比剂前后和多个时间点的血液和左心室心肌的各自 R(1)测量值，比较了其与参考多点 SR 方法的相关性。
所提出的方法和参考多点方法的 R(1)测量值具有很强的相关性（r>0.88，P<10(-5)），并且具有良好的一致性（平均差异±1.96 标准偏差 0.131±0.317/0.018±0.140s(-1)，分别用于血液/心肌）。
所提出的定量首过灌注 CMR 方法可在 523ms 的总采集时间内，在 3 个心脏短轴切片中测量准确的 R(1)值，用于定量 AIF 和心肌壁造影剂浓度。
