In Vivo Visualization of Brain Vasculature in Alzheimer's Disease Mice by High-Frequency Micro-Doppler Imaging

Objective: Cerebrovascular disorders are associated with Alzheimer's disease (AD). Functional analysis of the cerebral vasculature requires an in vivo approach to visualize the blood flow in small animal brains. This paper proposes a high-frequency micro-Doppler imaging (HF mu DI) technology for mapping mouse cerebral vasculature. Methods: HF mu DI used a 40-MHz transducer with an ultrafast ultrasound imaging technology that enabled in vivo visualization of the mouse brain up to 3mmin depth; furthermore, a minimal vessel diameter of 48 mu m could be determined. Results: Animal experiments determined that the cortical and hippocampal vessel density in young wild-type (WT) mice was similar to that in middle-aged WT mice. However, compared with the vessel density in middle-aged WT mice, that in middle-aged mice with AD was significantly lower, particularly in the hippocampus. Discussion: In vivo observation of cerebral vasculature demonstrated the effectiveness of HF mu DI for the preclinical study of AD, and a potential way for human diagnosis was provided.