Which imaging modality is most sensitive for detecting diffuse axonal injury?

Which imaging modality is most sensitive for detecting diffuse axonal injury?

• A. FDG-PET imaging.
• B. MRI with SWI or DTI.
• C. Noncontrast CT scan.
• D. Ultrasound.

Answer: (B)

Diffuse axonal injury involves microscopic damage to white-matter tracts, which is often invisible on CT. The imaging approach that best uncovers these subtle changes is MRI using advanced sequences like diffusion tensor imaging and susceptibility-weighted imaging. DTI detects disruptions in the directionality of water diffusion along axons, highlighting fiber tract injury, while SWI reveals microhemorrhages that frequently accompany DAI. This combination increases sensitivity far beyond what CT can provide. Noncontrast CT may be normal despite DAI, ultrasound isn’t used for intracranial parenchyma assessment, and metabolic imaging like FDG-PET doesn’t target the structural axonal injuries as effectively. So MRI with SWI or DTI is the most sensitive option for detecting diffuse axonal injury.

Diffuse axonal injury involves microscopic damage to white-matter tracts, which is often invisible on CT. The imaging approach that best uncovers these subtle changes is MRI using advanced sequences like diffusion tensor imaging and susceptibility-weighted imaging. DTI detects disruptions in the directionality of water diffusion along axons, highlighting fiber tract injury, while SWI reveals microhemorrhages that frequently accompany DAI. This combination increases sensitivity far beyond what CT can provide. Noncontrast CT may be normal despite DAI, ultrasound isn’t used for intracranial parenchyma assessment, and metabolic imaging like FDG-PET doesn’t target the structural axonal injuries as effectively. So MRI with SWI or DTI is the most sensitive option for detecting diffuse axonal injury.