Arterial Transit Time Mapping Obtained by Pulsed Continuous 3D ASL Imaging with Multiple Post-Label Delay Acquisitions: Comparative Study with PET-CBF in Patients with Chronic Occlusive Cerebrovascular Disease.
Arterial transit time (ATT) is most crucial for measuring absolute cerebral blood flow (CBF) by arterial spin labeling (ASL), a noninvasive magnetic resonance (MR) perfusion assessment technique, in patients with chronic occlusive cerebrovascular disease. We validated ASL-CBF and ASL-ATT maps calculated by pulsed continuous ASL (pCASL) with multiple post-label delay acquisitions in patients with occlusive cerebrovascular disease. Fifteen patients underwent MR scans, including pCASL, and positron emission tomography (PET) scans with 15O-water to obtain PET-CBF. MR acquisitions with different post-label delays (1.0, 1.5, 2.0, 2.5 and 3.0 sec) were also obtained for ATT correction. The theoretical framework of 2-compartmental model (2CM) was also used for the delay compensation. ASL-CBF and ASL-ATT were calculated based on the proposed 2CM, and the effect on the CBF values and the ATT correction characteristics were discussed. Linear regression analyses were performed both on pixel-by-pixel and region-of-interest bases in the middle cerebral artery (MCA) territory. There were significant correlations between ASL-CBF and PET-CBF both for voxel values (r = 0.74 ± 0.08, slope: 0.87 ± 0.22, intercept: 6.1 ± 4.9) and for the MCA territorial comparison in both affected (R2 = 0.67, y = 0.83x + 6.3) and contralateral sides (R2 = 0.66, y = 0.74x + 6.3). ASL-ATTs in the affected side were significantly longer than those in the contralateral side (1.51 ± 0.41 sec and 1.12 ± 0.30 sec, respectively, p <0.0005). CBF measurement using pCASL with delay compensation was feasible and fairly accurate even in altered hemodynamic states.
Biomedical Imaging Research Center, University of Fukui, Eiheiji, Fukui, Japan.
Tetsuya
T
Tsujikawa
Department of Radiology, Faculty of Medical Sciences, University of Fukui, Eiheiji, Fukui, Japan.
Hirohiko
H
Kimura
GE Healthcare Japan, Hino, Tokyo, Japan.
Tsuyoshi
T
Matsuda
Department of Radiology, Faculty of Medical Sciences, University of Fukui, Eiheiji, Fukui, Japan.|Department of Medical Imaging, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan.
Yasuhiro
Y
Fujiwara
Department of Neurosurgery, Faculty of Medical Sciences, University of Fukui, Eiheiji, Fukui, Japan.
Makoto
M
Isozaki
Department of Neurosurgery, Faculty of Medical Sciences, University of Fukui, Eiheiji, Fukui, Japan.
Ken-Ichiro
K
Kikuta
Biomedical Imaging Research Center, University of Fukui, Eiheiji, Fukui, Japan.
Hidehiko
H
Okazawa
D000328:Adult; D000368:Aged; D002560:Cerebrovascular Circulation; D002561:Cerebrovascular Disorders / Q000000981:diagnostic imaging / Q000503:physiopathology; D002908:Chronic Disease; D005260:Female; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D008955:Models, Cardiovascular; D049268:Positron-Emission Tomography; D063177:Pulse Wave Analysis