Diffuse Axonal Injury Classification
The Diffuse Axonal Injury Classification was first proposed by Adams in 1989 1) and divides diffuse axonal injury (DAI) into three grades:
grade I : involves grey-white matter interfaces most commonly : parasagittal regions of frontal lobes, periventricular temporal lobes less commonly : parietal and occipital lobes, internal and external capsules, and cerebellum often inapparent on conventional imaging may have changes on MRS 3
grade II : involves corpus callosum in addition to stage I locations observed in approximately 20% of patients most commonly : posterior body and splenium but does advance anteriorly with increasing severity of injury most frequently unilateral may be seen on SWI 3
grade III : involves brainstem in addition to stage I and II locations most commonly : rostral midbrain, superior cerebellar peduncles, medial lemnisci and corticospinal tracts.
DTI with 3-D fiber tractography can visualize acute axonal shearing injury, which may have prognostic value for the cognitive and neurological sequelae of traumatic brain injury 2).