Nordio Giovanna, Henningsson Markus, Chiribiri Amedeo, Villa Adriana D M, Schneider Torben, Botnar René M
Division of Imaging Science and Biomedical Engineering, King's College London, London, UK.
Philips Health Systems, London, UK.
J Magn Reson Imaging. 2017 Jul;46(1):218-227. doi: 10.1002/jmri.25575. Epub 2017 Feb 2.
To propose a 3D quantitative high-resolution T mapping technique, called 3D SASHA (saturation-recovery single-shot acquisition), which combines a saturation recovery pulse with 1D-navigator-based-respiratory motion compensation to acquire the whole volume of the heart in free breathing. The sequence was tested and validated both in a T phantom and in healthy subjects.
The 3D SASHA method was implemented on a 1.5T scanner. A diaphragmatic navigator was used to allow free-breathing acquisition and the images were acquired with a resolution of 1.4 × 1.4 × 8 mm . For assessment of accuracy and precision the sequence was compared with the reference gold-standard inversion-recovery spin echo (IRSE) pulse sequence in a T phantom, while for the in vivo studies (10 healthy volunteers) 3D SASHA was compared with the clinically used 2D MOLLI (3-3-5) and 2D SASHA protocols.
There was good agreement between the T values measured in a T phantom with 3D SASHA and the reference IRSE pulse sequences (1111.6 ± 31 msec vs. 1123.6 ± 8 msec, P = 0.9947). Mean and standard deviation of the myocardial T values in healthy subjects measured with 2D MOLLI, 2D SASHA, and 3D SASHA sequences were 881 ± 40 msec, 1181.3 ± 32 msec, and 1153.6 ± 28 msec respectively.
The proposed 3D SASHA sequence allows for high-resolution free-breathing whole-heart T -mapping with T values in good agreement with the 2D SASHA and improved precision.
2 Technical Efficacy: Stage 1 J. MAGN. RESON. IMAGING 2017;46:218-227.
提出一种三维定量高分辨率T映射技术，称为3D SASHA（饱和恢复单次采集），该技术将饱和恢复脉冲与基于一维导航器的呼吸运动补偿相结合，以在自由呼吸状态下采集整个心脏容积。该序列在T模型和健康受试者中均进行了测试和验证。
3D SASHA方法在1.5T扫描仪上实现。使用膈肌导航器实现自由呼吸采集，图像采集分辨率为1.4×1.4×8 mm。为评估准确性和精密度，该序列在T模型中与参考金标准反转恢复自旋回波（IRSE）脉冲序列进行比较，而在体内研究（10名健康志愿者）中，3D SASHA与临床使用的二维MOLLI（3-3-5）和二维SASHA协议进行比较。
在T模型中用3D SASHA测量的T值与参考IRSE脉冲序列之间具有良好的一致性（1111.6±31毫秒对1123.6±8毫秒，P = 0.9947）。用二维MOLLI、二维SASHA和3D SASHA序列测量的健康受试者心肌T值的平均值和标准差分别为881±40毫秒、1181.3±32毫秒和1153.6±28毫秒。
所提出的3D SASHA序列允许进行高分辨率自由呼吸全心T映射，其T值与二维SASHA具有良好的一致性且精度有所提高。
2 技术效能：1期 《磁共振成像杂志》2017年；46：218 - 227。
