Changes in Rat Brain Tissue Microstructure and Stiffness during the Development of Experimental Obstructive...

Area of Science:

• Neuroscience
• Biophysics
• Medical Imaging

Background:

• Neural injury mechanisms in hydrocephalus remain unclear.
• In-vivo brain changes during hydrocephalus progression require detailed characterization.

Purpose of the Study:

• To investigate brain deformation, microstructural, and mechanical property changes during obstructive hydrocephalus development in a rat model.
• To utilize multimodal magnetic resonance (MR) imaging for in-vivo analysis.

Main Methods:

• Obstructive hydrocephalus induced via kaolin injection in Sprague-Dawley rats.
• Multimodal MR imaging (9.4T) including T2-weighted, MR elastography, and diffusion tensor imaging (DTI).
• Imaging performed at multiple time points: pre-injection, and 3, 7, 16 days post-injection.

Main Results:

• Ventricular enlargement correlated with decreased cortical gray matter thickness and caudate-putamen area.
• Significant alterations in corpus callosum/periventricular white matter (CC+PVWM) and cortical gray matter microstructure observed.
• Regional variations in compression and microstructural changes noted, with modest changes in mechanical properties compared to diffusion changes.

Conclusions:

• Characterized temporal changes in brain tissue microstructure, water content, and stiffness associated with ventricular enlargement.
• Demonstrated regional variability in microstructural alterations and temporal variation in tissue stiffness during hydrocephalus development.
• Highlighted that ventricular enlargement impacts multiple brain regions beyond CC+PVWM and ventral internal capsule.