Introduction: It is essential to measure cerebral hemodynamics in making decision in the treatment of occlusive cerebrovascular disease (CVD). Arterial spin labeling (ASL) magnetic resonance imaging (MRI) is one of the techniques of perfusion MRI to measure cerebral hemodynamics noninvasively and requires a shorter acquisition time. It is reported ASL-MRI have comparable reliability of cerebral blood flow (CBF) quantification in healthy subjects. However, it is also reported ASL-CBF are affected by transit delay in the ischemic region. The objective of this study is to clarify how we can use and what is the limitation of this technique in the treatment of occlusive CVD at present.
Methods: Arterial spin labeling(ASL) and dynamic susceptibility contrast (DSC) MRI were performed to the patients of occlusive CVD (arteriosclerosis; 10 cases, moymoya disease; 14 cases) at the same examination. SPECT and PET scan were performed to the arteriosclerosis cases and moyamoya disease cases, respectively, within one month interval of MRI examination.
Results: (1) ASL-CBF maps showed high spatial resolution and were able to depict regional and/or global CBF decrease that correspond to the clinical symptoms of the patients. (2) ASL-CBF value corresponded better with that by other modalities, compared to DSC-CBF. (3) The patients with arteriosclerosis had better correlation of CBF between MRI and other modalities than that of moyamoya disease patients. The mean transit time (MTT) by DSC-MRI showed larger perfusion delay in the patients with moyamoya disease, suggesting that the reliability of CBF quantification is lower in the patient with moyamoya disease.
Conclusions: ASL-MRI could provide adequate information of CBF change with better spatial and temporal resolution. ASL-CBF corresponded better quantitativity in CBF measurement compared to DSC-CBF. Transit delay may affected ASL measurement. Therefore, caution must be exercised when using ASL-CBF values in stroke imaging.
Patient Care: This study will help neurosurgeons in making decision in the treatment of occlusive cerebrovascular disease.
Learning Objectives: By the conclusion of this session, participants should be able to describe the usefulness and limitation of ASL-MRI technique in the treatment of occlusive cerebrovascular disease