灌注MRI可用于评估、预测和监测头颈癌患者中危及器官的放射性毒性。动脉自旋标记（ASL）可能是对传统灌注MRI的有吸引力的替代方法，不需要使用对比剂。然而，目前对于ASL在头颈区健康组织中的性能和特性还知之甚少。因此，本研究的目的是优化并评估多延迟假连续ASL（pCASL）在头颈区的应用，探索血流（BF）、通过时间和BF定量所需的T1值的名义值和测量重复性。20名健康志愿者参与了四次多延迟pCASL扫描。感兴趣的区域包括腮腺、颌下腺、扁桃体和小脑（作为参照）。BF的名义值是志愿者每次重复的平均值，计算了BF的重复性系数和受试者内重复性系数（wCV）。研究了T1（地图与队列平均值）和通过时间校正对BF的影响。腮腺的平均BF（± SE）为55.7±3.1 ml/100 g/min，颌下腺为41.2±2.8 ml/100 g/min，扁桃体为32.3±2.2 ml/100 g/min。腮腺的重复性最好（wCV=13.3%-16.1%），其次是颌下腺和扁桃体（wCV=20.0%-24.6%）。平均而言，T1和通过时间校正对BF的影响有限，尽管在个体采集中存在显著偏差。总之，我们证明了使用多延迟pCASL在头颈区进行BF测量的可行性，并报告了头颈区各种组织中的名义BF值、BF重复性、T1和通过时间的影响。©2023年由约翰·威利及其子公司出版发行的《NMR in Biomedicine》。

Perfusion MRI is promising for the assessment, prediction, and monitoring of radiation toxicity in organs at risk in head and neck cancer. Arterial spin labeling (ASL) may be an attractive alternative for conventional perfusion MRI, that does not require the administration of contrast agents. However, currently, little is known about the characteristics and performance of ASL in healthy tissues in the head and neck region. Therefore, the purpose of this study was to optimize and evaluate multidelay pseudocontinuous ASL (pCASL) for the head and neck region and to explore nominal values and measurement repeatability for the blood flow (BF), and the transit time and T1 values needed for BF quantification in healthy tissues. Twenty healthy volunteers underwent a scan session consisting of four repeats of multidelay pCASL (postlabel delays: 1000, 1632, 2479 ms). Regions of interest were defined in the parotid glands, submandibular glands, tonsils, and the cerebellum (as a reference). Nominal values of BF were calculated as the average over four repeats per volunteer. The repeatability coefficient and within-subject coefficient of repeatability (wCV) of BF were calculated. The effect of T1 (map vs. cohort average) and transit time correction on BF was investigated. The mean BF (± SE) was 55.7 ± 3.1 ml/100 g/min for the parotid glands, 41.2 ± 2.8 ml/100 g/min for the submandibular glands, and 32.3 ± 2.2 ml/100 g/min for the tonsils. The best repeatability was found in the parotid glands (wCV = 13.3%-16.1%), followed by the submandibular glands and tonsils (wCV = 20.0%-24.6%). On average, the effect of T1 and transit time correction on BF was limited, although substantial bias occurred in individual acquisitions. In conclusion, we demonstrated the feasibility of BF measurements in the head and neck region using multidelay pCASL and reported on nominal BF values, BF repeatability, the effect of T1, and transit time in various tissues in the head and neck region.© 2023 The Authors. NMR in Biomedicine published by John Wiley & Sons Ltd.