Details

Autor(en) / Beteiligte

• Hirschler, Lydiane
• Munting, Leon P.
• Khmelinskii, Artem
• Teeuwisse, Wouter M.
• Suidgeest, Ernst
• Warnking, Jan M.
• Weerd, Louise
• Barbier, Emmanuel L.
• Osch, Matthias J.P.

Titel

Transit time mapping in the mouse brain using time‐encoded pCASL

Ist Teil von

• NMR in biomedicine, 2018-02, Vol.31 (2), p.n/a

Ort / Verlag

England: Wiley Subscription Services, Inc

Erscheinungsjahr

2018

Quelle

MEDLINE

Beschreibungen/Notizen

• The cerebral blood flow (CBF) is a potential biomarker for neurological disease. However, the arterial transit time (ATT) of the labeled blood is known to potentially affect CBF quantification. Furthermore, ATT could be an interesting biomarker in itself, as it may reflect underlying macro‐ and microvascular pathologies. Currently, no optimized magnetic resonance imaging (MRI) sequence exists to measure ATT in mice. Recently, time‐encoded labeling schemes have been implemented in rats and humans, enabling ATT mapping with higher signal‐to‐noise ratio (SNR) and shorter scan time than multi‐delay arterial spin labeling (ASL). In this study, we show that time‐encoded pseudo‐continuous arterial spin labeling (te‐pCASL) also enables transit time measurements in mice. As an optimal design that takes the fast blood flow in mice into account, time encoding with 11 sub‐boli of 50 ms is proposed to accurately probe the inflow of labeled blood. For perfusion imaging, a separate, traditional pCASL scan was employed. From the six studied brain regions, the hippocampus showed the shortest ATT (169 ± 11 ms) and the auditory/visual cortex showed the longest (284 ± 16 ms). Furthermore, ATT was found to be preserved in old wild‐type mice. In a mouse with an induced carotid artery occlusion, prolongation of ATT was shown. In conclusion, this study shows the successful implementation of te‐pCASL in mice, making it possible, for the first time, to measure ATT in mice in a time‐efficient manner. With time‐encoded pseudo‐continuous arterial spin labeling (te‐pCASL), time‐efficient multi‐delay sampling can be performed to estimate the arrival of the arterial spin labeling (ASL) signal in the brain. In this study, we show the successful implementation of a Hadamard‐12‐encoded pCASL sequence in mice, yielding perfusion‐weighted images at 11 time points (a). By fitting a perfusion model to the ASL signal time course (b), the arterial transit time (ATT) and cerebral blood flow (CBF) can be estimated and mapped (c).