Evidence of axon beading and loss of extracellular fluid following perfusion and fixation of the marmoset brain

Previous work showed that advanced diffusion metrics (OGSE and μFA) are sensitive to microstructural changes between in vivo and ex vivo marmoset brain tissues. Here, we utilized Monte Carlo simulations to investigate potential microstructure changes that could be occurring during tissue perfusion and fixation. A comparison between simulations and experiments showed that beading and decreased extracellular space are in agreement with the experimental trends observed. Changing microstructural properties during these processes has implications for studies that compare ex vivo tissue samples with in vivo findings.