Multislice, dual-imaging sequence for increasing the dynamic range of the contrast-enhanced blood signal and CNR of myocardial enhancement at 3T
Multislice, dual-imaging sequence for increasing the dynamic range of the contrast-enhanced blood signal and CNR of myocardial enhancement at 3T
复制标题
DOI：
10.1002/jmri.20471
复制
发表时间：
2006-01-01
影响因子：
4.4
通讯作者：
Axel, L
中科院分区：
文献类型：
--
作者：
Kim, D;Axel, L
目的：建立一种多层首过灌注成像序列，提高血液增强信号的有效动态范围和心肌壁增强的噪比（CNR）。材料和方法：对混合回波平面成像（EPI）脉冲序列进行修改，以获取动脉输入功能（AIF）和心肌的数据，在单次饱和脉冲后使用两种不同的饱和恢复时间延迟（td）和空间分辨率。5名健康受试者在接受高剂量造影剂注射期间，在每次心跳的三个短轴水平上进行3T扫描。将血液t -1加权信号时间曲线转换为AIF，采用模拟实验的经验转换表。结果：在所有受试者中，与长期td方案相比，短td方案计算的AIF畸变较小，且较高（峰值浓度：5.0 +/- 1.0 mM vs. 3.0 +/- 0.6 mM; P < 0.01）。结合EPI、长TD、大剂量造影剂和3T成像，心肌峰值增强相对较强（CNR 11.9 +/- 3.3）。结论：我们的3T双成像方法似乎有望获得相对准确的AIF和每次心跳多片心肌壁增强的高CNR。
Purpose: To develop a multislice, first-pass perfusion imaging sequence for increasing the effective dynamic range of the contrast-enhanced blood signal and the contrast-to-noise ratio (CNR) of myocardial wall enhancement.Materials and Methods: A hybrid echo-planar imaging (EPI) pulse sequence was modified to acquire data for both the arterial input function (AIF) and the myocardium, using two different saturation-recovery time delays (TDs) and spatial resolutions, after a single saturation pulse. Five healthy subjects were scanned at 3T in three short-axis levels of the heart per heartbeat during passage of a high-dose bolus of contrast agent. The T-1-weighted signal-time curve of the blood was converted to AIF using empirical conversion tables derived from phantom experiments.Results: In all subjects the calculated AIF was consistently less distorted and higher for the short-TD protocol than for the long-TD protocol (peak concentration: 5.0 +/- 1.0 mM vs. 3.0 +/- 0.6 mM; P < 0.01). A combination of EPI, long TD, high-dose bolus of contrast agent, and 3T imaging yielded relatively strong peak enhancement in the myocardium (CNR 11.9 +/- 3.3).Conclusion: Our dual-imaging approach at 3T seems promising for acquiring both a relatively accurate AIF and a high CNR of myocardial wall enhancement in multiple slices per heartbeat.