SNAP and TOF are two non-contrast enhanced intracranial magnetic resonance angiography (MRA) techniques. Both techniques rely on incoming blood to produce a signal, although they have different sensitivity to blood flow velocity. In human beings, SNAP-MRA and TOF-MRA were frequently observed to show discrepancy in visibility of distal intracranial arteries. Whether this signal feature difference is associated with the blood flow of intracranial arteries has not been validated in patients. White matter hyperintensity is frequently observed in elderly and neurodegenerative patients, and may be contributed by the impairment of intracranial arteries. Whether the discrepancy between TOF-MRA and SNAP-MRA can serve as an imaging biomarker of the health of intracranial arteries and is associated with white matter hyperintensity remains unclear. In this study, we aim to characterize the disagreement of vessel visibility in SNAP and TOF, and explore its associations with blood flow and white matter lesions in patients with carotid artery atherosclerosis. In this study, we found this disagreement to be due to velocity sensitivity. The disagreement in the distal branches of the middle cerebellar and anterior cerebellar arteries were shown to be associated with white matter lesion volume. / 2022-06-04T00:00:00Z