DIFFUSE AXONAL INJURY IN CRANIOCEREBRAL TRAUMA - A COMPARATIVE HISTOLOGIC AND IMMUNOHISTOCHEMICAL STUDY

Axonal swellings are the major histologic hallmark of diffuse axonal i njury in craniocerebral trauma. In this study, we compared conventiona l histologic and immunohistochemical methods for demonstrating axonal swellings in 11 cases of head trauma. Brain regions known to be suscep tible to diffuse axonal injury were examined with conventional hematox ylin-eosin and silver (Bodian) stains and immuno-histochemical markers for neurofilaments, ubiquitin, and tau and beta/A4-amyloid. A quantit ative assessment of the axonal swellings visualized with each stain wa s made. In all but one case, axonal swellings were identified with the hematoxylin-eosin stain. By contrast, both the silver and neurofilame nt stains demonstrated fewer axonal swellings and were often difficult to interpret due to staining of normal axons. In the majority of case s, the ubiquitin stain revealed the greatest number of axonal swelling s. Axonal swellings were not visualized with the tau or beta/A4-amyloi d antibodies. We conclude that the standard hematoxylin-eosin stain re mains a reliable method for the detection of axonal swellings in crani ocerebral trauma and is superior to the Bodian and neurofilament stain s. Identification and quantitative assessment of diffuse axonal injury is aided by the use of immunocytochemical staining for ubiquitin.