Correlation of computed tomography findings and serum brain damage markers following severe head injury

The objective of our study was to investigate the association between the initial levels of serum S-100B protein and neuron specific enolase and the severity of radiologically visible brain damage and outcome after severe head injury. Admission computed tomography (CT) scans of forty-four patients with severe head injury were analysed. Initial levels of S-100B protein and neuron specific enolase were compared between the different outcome groups at 6 month, the different categories of the Marshall classification, the presence of traumatic subarachnoid haemorrhage, the type of haematoma and the volume of contusion. Serum S-100B was significantly higher in patients with unfavourable outcome (1.1 micrograms/l versus 0.3 microgram/l, p < 0.005, Mann-Whitney U test). In diffuse injury, unfavourable outcome significantly increased with higher Marshall grades (p < 0.05). There was a significant correlation between the four grades of diffuse injury and initial serum S-100B protein (r = 0.48, p < 0.001). Patients with focal mass lesions and a favourable outcome after 6 month had significantly lower S-100B values than those who had an unfavourable outcome (0.51 microgram/l versus 1.3 micrograms/l, p < 0.05). A significant correlation was demonstrated between the volume of contusion visible on CT scans and serum S-100B (r = 0.58, p < 0.001). In our study, initial serum S-100B protein was a powerful predictor of outcome even within the same category of radiologically visible brain damage. Serum S-100B protein may provide independent information about the severity of primary brain damage after head injury.