Cytotoxic Edema Associated with Hemorrhage Predicts Poor Outcome after Traumatic Brain Injury.

Area of Science:

• Neuroimaging
• Neurology
• Radiology

Background:

• Computed tomography (CT) is standard for acute traumatic brain injury (TBI) evaluation.
• Magnetic resonance imaging (MRI) is underutilized but can reveal critical findings.
• Cytotoxic edema and microhemorrhages are important TBI indicators.

Purpose of the Study:

• To assess the association of early MRI findings (cytotoxic edema, hemorrhage) with TBI outcomes.
• To investigate the temporal evolution of edema in TBI.
• To determine if MRI findings predict clinical outcomes.

Main Methods:

• Prospective enrollment in the Traumatic Head Injury Neuroimaging Classification study.
• Blinded MRI interpretation for diffusion-weighted lesions and hemorrhage.
• Quantification of apparent diffusion coefficient (ADC) values.
• Correlation of imaging findings with Glasgow Outcome Scale Extended (GOSE) scores.

Main Results:

• 82/161 patients showed diffusion-weighted imaging (DWI) lesions with hypointense ADC near hemorrhage.
• Lowest ADC values were observed within 24 hours post-injury, indicating cytotoxic edema.
• Cytotoxic edema on MRI (OR 2.91) and TBI severity (OR 2.51) independently predicted poor outcomes (GOSE ≤6).

Conclusions:

• Early MRI, particularly DWI/ADC lesions, identifies cytotoxic edema in TBI.
• Edema characteristics evolve from cytotoxic to vasogenic in the subacute phase.
• Early cytotoxic edema on MRI is a significant predictor of worse clinical outcomes in TBI patients with hemorrhage.