The hour-glass model of corpus callosum injury

In this retrospective study, the authors analyze the frequency, anatomical distribution and the clinical outcome of 44 patients after severe head injury, with and without lesions of the corpus callosum (CC). 44 patients with severe head injury (GCS<9 on admission), who were admitted to the intensive care unit of the Department of Neurosurgery after trauma, underwent early MR-tomography (T1, T2 and FLAIR sequences) in addition to CCT performed on admission. CC lesions were found in about 1/3 of patients with severe head injury. Posterior (splenium) lesions of the CC were three times more common than anterior lesions. Patients with CC injury were much younger compared to patients without CC injury (25 versus 34 years). The Glasgow Outcome Scale (GOS) score after six months was poor (death, persistent vegetative state, severe disability, GOS>3) in all patients with CC injury when compared to patients without CC injury (GOS<4). CC lesions are an important parameter in the assessment of severe brain trauma, hinting at the mechanism of injury as well as the outcome of patients. If a patient does not awake after blunt head injury, MRT scans (including FLAIR sequences) are indicated. A CC lesion alone is not the cause of prolonged coma but indicates a severe diffuse injury resulting in functional deorganization of the brain. The mechanisms of CC injury are discussed and a new pathophysiological model, based on the hour-glass analogy, is presented.