Mesoscopic vascular alterations in Alzheimer's disease

Area of Science:

• Neuroscience
• Cerebrovascular Research
• Medical Imaging

Background:

• Cerebrovascular alterations are implicated in Alzheimer's disease (AD) pathology.
• Understanding these changes is limited by a lack of data on mesoscopic vasculature (24-240 µm diameter).

Purpose of the Study:

• To investigate three-dimensional alterations in mesoscopic cerebrovasculature in Alzheimer's disease (AD).
• To correlate vascular changes with amyloid-beta (Aβ) and phosphorylated tau (p-tau) protein deposits.

Main Methods:

• Utilized label-free, serial-sectioning optical coherence tomography (OCT) for mesoscopic cerebrovasculature reconstruction.
• Analyzed dorsolateral prefrontal cortex (DLPFC) samples from AD and control subjects.
• Quantified vascular network metrics including volume fraction, vessel length density, and branch density.

Main Results:

• AD samples exhibited significantly reduced volume fraction, vessel length density, and branch density compared to controls.
• Observed negative trends between certain vascular metrics and the density of Aβ and p-tau deposits.

Conclusions:

• Significant mesoscopic cerebrovasculature alterations are present in the DLPFC of AD samples.
• This study bridges the knowledge gap between micro- and macroscopic cerebrovascular pathologies in AD.
• Serial-sectioning OCT provides novel insights into mesoscopic cerebrovasculature.