Evaluation of 3D stack‐of‐spiral turbo FLASH acquisitions for pseudo‐continuous and velocity‐selective ASL–derived brain perfusion mapping

• Published in: Magnetic resonance in medicine Vol. 90; no. 3; pp. 939 - 949
• Main Authors: Zhu, Dan, Xu, Feng, Liu, Dapeng, Hillis, Argye Elizabeth, Lin, Doris, Zijl, Peter C. M., Qin, Qin
• Format: Journal Article
• Language: English
• Published: United States Wiley Subscription Services, Inc 01.09.2023
• Subjects: Acceleration; Blood flow; Blood volume; Blurring; Brain - blood supply; Brain Mapping; Cerebral blood flow; cerebral blood volume; Cerebrospinal fluid; Cerebrovascular Circulation - physiology; Contamination; Efficiency; Excitation; Flow mapping; Humans; Imaging, Three-Dimensional - methods; Perfusion; pseudo‐continuous ASL; Spin Labels; stack‐of‐spiral turbo FLASH; Temporal resolution; Velocity; velocity‐selective arterial spin labeling; pseudo-continuous ASL; cerebral blood flow; stack-of-spiral turbo FLASH; velocity-selective arterial spin labeling; cerebral blood volume
• ISSN: 0740-3194; 1522-2594
• DOI: 10.1002/mrm.29681

Purpose The most‐used 3D acquisitions for ASL are gradient and spin echo (GRASE)– and stack‐of‐spiral (SOS)–based fast spin echo, which require multiple shots. Alternatively, turbo FLASH (TFL) allows longer echo trains, and SOS‐TFL has the potential to reduce the number of shots to even single‐shot, thus improving the temporal resolution. Here we compare the performance of 3D SOS‐TFL and 3D GRASE for ASL at 3T. Methods The 3D SOS‐TFL readout was optimized with respect to fat suppression and excitation flip angles for pseudo‐continuous ASL– and velocity‐selective (VS)ASL–derived cerebral blood flow (CBF) mapping as well as for VSASL‐derived cerebral blood volume (CBV) mapping. Results were compared with 3D GRASE readout on healthy volunteers in terms of perfusion quantification and temporal SNR (tSNR) efficiency. CBF and CBV mapping derived from 3D SOS‐TFL–based ASL was demonstrated on one stroke patient, and the potential for single‐shot acquisitions was exemplified. Results SOS‐TFL with a 15° flip angle resulted in adequate tSNR efficiency with negligible image blurring. Selective water excitation was necessary to eliminate fat‐induced artifacts. For pseudo‐continuous ASL– and VSASL‐based CBF and CBV mapping, compared to the employed four‐shot 3D GRASE with an acceleration factor of 2, the fully sampled 3D SOS‐TFL delivered comparable performance (with a similar scan time) using three shots, which could be further undersampled to achieve single‐shot acquisition with higher tSNR efficiency. SOS‐TFL had reduced CSF contamination for VSASL‐CBF. Conclusion 3D SOS‐TFL acquisition was found to be a viable substitute for 3D GRASE for ASL with sufficient tSNR efficiency, minimal relaxation‐induced blurring, reduced CSF contamination, and the potential of single‐shot, especially for VSASL.