Institute of Neuroradiology, Christian-Albrechts-Universität, Kiel, Germany.
NMR Biomed. 2011 May;24(4):404-12. doi: 10.1002/nbm.1605. Epub 2010 Nov 8.
Continuous artery-selective spin labeling (CASSL) is based on a standard continuous arterial spin labeling sequence with adiabatic flow-driven inversion and an amplitude-modulated control experiment, and has been proposed recently as a new method for the noninvasive flow territory mapping of cerebral arteries. Spatial selectivity is achieved by the rotation of a tilted labeling plane about the axis of a selected artery, which restricts the tagging pulses to the same spatial position for the vessel of interest but, for any other adjacent and parallel artery, the locus of resonance will vary in time and saturates the blood at a certain distance to the labeling focus. In numerical simulations and in a volunteer study, the key labeling parameters of CASSL were investigated with the goal of increasing the spatial selectivity whilst maintaining sufficient labeling efficiency, in order to selectively label the blood in small intracranial arteries distal to the circle of Willis. The optimized labeling parameters were employed in vivo and adapted to different vascular geometries. The labeling of small intracranial branches of the anterior, middle and posterior cerebral arteries in close vicinity to other vessels yielded clearly delineated perfusion territories and demonstrated the method's capability for highly selective perfusion measurements.
连续动脉选择性标记（CASSL）基于标准的连续动脉自旋标记序列，采用绝热流驱动反转和幅度调制控制实验，最近被提出作为一种新的非侵入性脑动脉血流区域映射方法。空间选择性是通过倾斜标记平面绕选定动脉的轴旋转来实现的，这将标记脉冲限制在感兴趣的血管的相同空间位置，但对于任何其他相邻的平行动脉，共振轨迹将随时间变化，并在距标记焦点一定距离处使血液饱和。在数值模拟和志愿者研究中，研究了 CASSL 的关键标记参数，目的是在保持足够标记效率的同时提高空间选择性，以便选择性地标记 Willis 环远端的颅内小动脉中的血液。优化的标记参数用于体内，并适应不同的血管几何形状。对靠近其他血管的前、中、后脑动脉的颅内小分支进行标记，得到了清晰的灌注区域，并证明了该方法在高度选择性灌注测量方面的能力。
