Gutjahr Fabian T, Kampf Thomas, Winter Patrick, Meyer Cord B, Williams Tatjana, Jakob Peter M, Bauer Wolfgang R, Ziener Christian H, Helluy Xavier
Universität Würzburg, Lehrstuhl für Experimentelle Physik 5, Am Hubland, 97074, Würzburg, Germany.
Comprehensive Heart Failure Center, Core Facility Imaging, Straubmühlweg 2a, 97078, Würzburg, Germany.
Magn Reson Med. 2015 Dec;74(6):1705-15. doi: 10.1002/mrm.25526. Epub 2014 Dec 1.
A method for the quantification of perfusion in murine myocardium is demonstrated. The method allows for the reconstruction of perfusion maps on arbitrary time points in the heart cycle while addressing problems that arise due to the irregular heart beat of mice.
A flow-sensitive alternating inversion recovery arterial spin labeling method using an untriggered FLASH-read out with random sampling is used. Look-Locker conditions are strictly maintained. No dummy pulses or mechanism to reduce deviation from Look-Locker conditions are needed. Electrocardiogram and respiratory data are recorded for retrospective gating and triggering. A model-based technique is used to reconstruct missing k-space data to cope with the undersampling inherent in retrospectively gated methods. Acquisition and reconstruction were validated numerically and in phantom measurements before in vivo experimentation.
Quantitative perfusion maps were acquired within a single slice measurement time of 11 min. Perfusion values are in good accordance to literature values. Myocardial infarction could be clearly visualized and results were confirmed with histological results.
The proposed method is capable of producing quantitative perfusion maps on arbitrary positions in the heart cycle within a short measurement time. The method is robust against irregular breathing patterns and heart rate changes and can be implemented on all scanners.
展示一种定量检测小鼠心肌灌注的方法。该方法能够重建心动周期中任意时间点的灌注图，同时解决因小鼠心跳不规则而产生的问题。
采用一种流敏感型交替反转恢复动脉自旋标记方法，使用无触发的快速小角度激发读出并进行随机采样。严格维持Look-Locker条件。无需虚拟脉冲或减少与Look-Locker条件偏差的机制。记录心电图和呼吸数据用于回顾性门控和触发。使用基于模型的技术重建缺失的k空间数据，以应对回顾性门控方法中固有的欠采样问题。在体内实验之前，通过数值模拟和体模测量对采集和重建进行了验证。
在11分钟的单层面测量时间内获取了定量灌注图。灌注值与文献值高度一致。心肌梗死能够清晰可视化，结果通过组织学结果得到证实。
所提出的方法能够在短测量时间内生成心动周期中任意位置的定量灌注图。该方法对不规则呼吸模式和心率变化具有鲁棒性，并且可以在所有扫描仪上实现。
