Medical Research Council (MRC), London Institute of Medical Sciences (LMS), Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, W12 0NN, UK.
Department of Chemistry, Imperial College London, South Kensington Campus, Exhibition Road, London, UK.
Eur Radiol. 2019 Jan;29(1):232-240. doi: 10.1007/s00330-018-5628-3. Epub 2018 Jul 10.
We investigated the feasibility and reproducibility of free-breathing motion-corrected multiple inversion time (multi-TI) pulsed renal arterial spin labelling (PASL), with general kinetic model parametric mapping, to simultaneously quantify renal perfusion (RBF), bolus arrival time (BAT) and tissue T.
In a study approved by the Health Research Authority, 12 healthy volunteers (mean age, 27.6 ± 18.5 years; 5 male) gave informed consent for renal imaging at 3 T using multi-TI ASL and conventional single-TI ASL. Glyceryl trinitrate (GTN) was used as a vasodilator challenge in six subjects. Flow-sensitive alternating inversion recovery (FAIR) preparation was used with background suppression and 3D-GRASE (gradient and spin echo) read-out, and images were motion-corrected. Parametric maps of RBF, BAT and T were derived for both kidneys. Agreement was assessed using Pearson correlation and Bland-Altman plots.
Inter-study correlation of whole-kidney RBF was good for both single-TI (r = 0.90), and multi-TI ASL (r = 0.92). Single-TI ASL gave a higher estimate of whole-kidney RBF compared to multi-TI ASL (mean bias, 29.3 ml/min/100 g; p <0.001). Using multi-TI ASL, the median T of renal cortex was shorter than that of medulla (799.6 ms vs 807.1 ms, p = 0.01), and mean whole-kidney BAT was 269.7 ± 56.5 ms. GTN had an effect on systolic blood pressure (p < 0.05) but the change in RBF was not significant.
Free-breathing multi-TI renal ASL is feasible and reproducible at 3 T, providing simultaneous measurement of renal perfusion, haemodynamic parameters and tissue characteristics at baseline and during pharmacological challenge.
• Multiple inversion time arterial spin labelling (ASL) of the kidneys is feasible and reproducible at 3 T. • This approach allows simultaneous mapping of renal perfusion, bolus arrival time and tissue T during free breathing. • This technique enables repeated measures of renal haemodynamic characteristics during pharmacological challenge.
我们研究了自由呼吸运动校正多次反转时间（multi-TI）脉冲肾动脉自旋标记（PASL），结合通用动力学模型参数映射，同时定量肾灌注（RBF）、对比剂到达时间（BAT）和组织 T 的可行性和可重复性。
在健康研究管理局批准的一项研究中，12 名健康志愿者（平均年龄 27.6±18.5 岁；5 名男性）同意在 3T 下进行多 TI ASL 和传统单 TI ASL 的肾脏成像。6 名志愿者使用硝化甘油（GTN）作为血管扩张剂挑战。使用流动敏感反转恢复（FAIR）准备，背景抑制和 3D-GRASE（梯度和自旋回波）读出，并进行运动校正。为两个肾脏衍生 RBF、BAT 和 T 的参数图。使用 Pearson 相关和 Bland-Altman 图评估一致性。
单 TI（r=0.90）和多 TI ASL（r=0.92）的整个肾脏 RBF 的研究间相关性良好。与多 TI ASL 相比，单 TI ASL 对整个肾脏 RBF 的估计更高（平均偏差 29.3ml/min/100g；p<0.001）。使用多 TI ASL，肾皮质的 T 中位数短于肾髓质（799.6ms 比 807.1ms，p=0.01），平均整个肾脏 BAT 为 269.7±56.5ms。GTN 对收缩压有影响（p<0.05），但 RBF 的变化不显著。
3T 下自由呼吸多 TI 肾 ASL 是可行和可重复的，可在基线和药物挑战期间同时测量肾灌注、血流动力学参数和组织特征。
• 肾脏的多次反转时间动脉自旋标记（ASL）在 3T 下是可行和可重复的。• 该方法允许在自由呼吸时同时映射肾灌注、对比剂到达时间和组织 T。• 该技术可在药物挑战期间重复测量肾血流动力学特征。
