Outcome after mild-to-moderate blunt head injury: effects of focal lesionsand diffuse axonal injury

Primary objective: A comparison of the effects of focal and diffuse axonal injury in mild-to-moderate traumatic brain injury (TBI). Research design: In a prospective longitudinal study of 138 consecutive pat ients suffering from TBI who were admitted to the Magdeburg University Hosp ital, 60 could be assessed neuropsychologically 8-31 days after trauma and 18-45 weeks later. Methods and procedures: GCS, CT-analysis, comprehensive neuropsychological assessment. Main results: The initial GCS-score was significantly correlated with outco me impairments of semantic fluency and memory in the Wechsler Similarities and in two clinical scales (Neurobehavioural Rating Scale, Frontal Lobe Sco re). The presence of CT-signs of DAI corresponded with deficits in tasks of response selection and suppression, the presence of focal contusions with results in the clinical scales, reaching significance for behavioural defic its with frontal contusions. Improvements between first and second assessme nts were pronounced in patients with signs of DAI. Conclusions: The data indicate that traumatic DAI results in mainly transie nt neuropsychological deficits. Focal frontal contusions result in more rel evant deficits at outcome that affect behaviour and, thus, impair rehabilit ation prognosis. It is concluded that even in clinically 'mild' TBI, progno sis and rehabilitation requirements should be established by early imaging and post-acute neuropsychological assessment.