Quantitative MRI analysis of brain volume changes due to controlled cortical impact

Area of Science:

• Neuroscience
• Biomedical Engineering
• Radiology

Background:

• Mild traumatic brain injury (TBI) is common, yet often lacks clear MRI findings correlating with symptoms.
• Quantitative MRI analysis is needed to understand the in vivo sequelae of TBI.

Purpose of the Study:

• To establish in vivo sequelae of TBI using quantitative MRI and a mechanical model.
• To investigate time-based morphological and physiological changes following controlled cortical impacts of varying severity.

Main Methods:

• A mechanical model of penetrating impact injury was used on Sprague-Dawley rats.
• Whole-brain MRI scans were performed before and hourly for 5 hours post-impact.
• Brain volume and anatomical structures were segmented for quantitative analysis.

Main Results:

• Elevated intracranial pressure (ICP) was observed in both lower and higher impact groups.
• A significant decrease in cerebrospinal fluid (CSF) volume was noted (35% lower, 65% higher impacts).
• Corpus callosum volume increased significantly post-impact, with concurrent increases in abnormal tissue and cerebral cortex atrophy.

Conclusions:

• Quantitative MRI can detect in vivo morphological and physiological changes after TBI.
• The study demonstrates significant CSF volume reduction and corpus callosum changes, correlating with injury severity.
• Findings provide a quantitative basis for understanding TBI pathology and its time course.