Which statement about diffuse axonal injury detection in the subacute phase is true?

Which statement about diffuse axonal injury detection in the subacute phase is true?

• A. CT is the best modality
• B. PET is the standard for DAI
• C. Ultrasound detects DAI best
• D. MRI with SWI/DTI is best for subacute DAI

Answer: (D)

Imaging in the subacute phase hinges on showing microscopic white-matter damage that isn’t always visible on CT. MRI with susceptibility-weighted imaging is particularly sensitive to tiny microhemorrhages in white matter tracts, which are common in diffuse axonal injury. Diffusion tensor imaging goes a step further by assessing the integrity of white-matter pathways through diffusion of water; injured axons disrupt diffusion patterns and lower fractional anisotropy, revealing axonal injury even when standard MRI looks benign. Because of these capabilities, MRI with SWI/DTI provides the most sensitive detection of subacute DAI. CT often misses these injuries, ultrasound has no role here, and PET isn’t the standard approach for diagnosing DAI.

Imaging in the subacute phase hinges on showing microscopic white-matter damage that isn’t always visible on CT. MRI with susceptibility-weighted imaging is particularly sensitive to tiny microhemorrhages in white matter tracts, which are common in diffuse axonal injury. Diffusion tensor imaging goes a step further by assessing the integrity of white-matter pathways through diffusion of water; injured axons disrupt diffusion patterns and lower fractional anisotropy, revealing axonal injury even when standard MRI looks benign. Because of these capabilities, MRI with SWI/DTI provides the most sensitive detection of subacute DAI. CT often misses these injuries, ultrasound has no role here, and PET isn’t the standard approach for diagnosing DAI.