Diffuse axonal injury in head injury: definition, diagnosis and grading.
Diffuse axonal injury is one of the most important types of brain damage that can occur as a result of non-missile head injury, and it may be very difficult to diagnose post mortem unless the pathologist knows precisely what he is looking for. Increasing experience with fatal non-missile head injury in man has allowed the identification of three grades of diffuse axonal injury. In grade 1 there is histological evidence of axonal injury in the white matter of the cerebral hemispheres, the corpus callosum, the brain stem and, less commonly, the cerebellum; in grade 2 there is also a focal lesion in the corpus callosum; and in grade 3 there is in addition a focal lesion in the dorsolateral quadrant or quadrants of the rostral brain stem. The focal lesions can often only be identified microscopically. Diffuse axonal injury was identified in 122 of a series of 434 fatal non-missile head injuries--10 grade 1, 29 grade 2 and 83 grade 3. In 24 of these cases the diagnosis could not have been made without microscopical examination, while in a further 31 microscopical examination was required to establish its severity.
Department of Neuropathology, University of Glasgow, Scotland.
J H
JH
Adams
D
D
Doyle
I
I
Ford
T A
TA
Gennarelli
D I
DI
Graham
D R
DR
McLellan
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001364:Awareness; D001369:Axons / Q000473:pathology; D001930:Brain Injuries / Q000175:diagnosis / Q000209:etiology* / Q000473:pathology; D002648:Child; D002675:Child, Preschool; D003337:Corpus Callosum / Q000473:pathology; D006259:Craniocerebral Trauma / Q000150:complications*; D005260:Female; D005724:Ganglia / Q000473:pathology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D011149:Pons / Q000473:pathology; D011712:Pyramidal Tracts / Q000473:pathology; D012887:Skull Fractures