Arterial spin-labeling MR imaging in moyamoya disease compared with SPECT imaging

Objective: Arterial spin-labeling (ASL) is a noninvasive magnetic resonance (MR) imaging method used to obtain brain perfusion information on various cerebrovascular diseases. We retrospectively compared the use of ASL-MRI and single-photon emission CT (SPECT) imaging to determine absolute cerebral blood flow (CBF) in moyamoya disease. Materials and methods: CBF examinations using ASL-MRI on 3-T MRI and SPECT imagings with iodine-123-N-isopropyl-p-iodoamphetamine at resting (rest-IMP) and after acetazolamide challenge (ACZ-IMP) were performed on 12 patients with moyamoya disease (men, 5; women, 7; age range/average (year), 7-66/35.0). The CBF values determined by ASL-MRI (ASL-value), rest-IMP (rest-IMP-value), and ACZ-IMP (ACZ-IMP-value) of cerebral hemispheres (24 sides) were measured with normalized CBF maps created from data of those 3 perfusion imaging methods. Cerebrovascular reactivity (CVR) was calculated as follows: {(ACZ-IMP-value) - (rest-IMP-value)}/(rest-IMP-value) x 100 (%). The ASL-value was compared with the rest-IMP-value, ACZ-IMP-value, and CVR. Results: The ASL-value, rest-IMP-value, ACZ-IMP-value, and CVR (average +/- standard deviation) were 26.6 +/- 14.8 (mL/100 g/min), 27.5 +/- 6.4 (mL/100 g/min), 37.1 +/- 13.2 (mL/100 g/min), and 35.9 +/- 44.3 (%), respectively. Significant relationships between the ASL-value versus (vs.) the rest-IMP-value (rs = 0.500, p < 0.05), the ASL-value vs. the ACZ-IMP-value (rs = 0.863, p < 0.01), and the ASL-value vs. the CVR (rs = 0.699, p < 0.01) were observed. Conclusion: Although the ASL-value was lower than the rest-IMP-value, the significant relationship between the ASL-value and the rest-IMP-value may suggest that perfusion imaging by ASL-MRI could be used to recognize the condition of brain perfusion. In particular, the stronger correlation coefficient between the ASL-value and ACZ-IMP-value might suggest that perfusion imaging by ASL-MRI could show the potentially dangerous zone for ischemia. (C) 2011 Elsevier Ireland Ltd. All rights reserved.