Effect of intracerebral lesions detected in early MRI on outcome after acute brain injury.

Abstract

In the present study we classified intracerebral lesions likely to influence the outcome of head injured patients according to localization, lesion type, lesion number and lesion volume. A score of intracerebral lesions based on findings in early MRI is presented. Early MRI studies were performed in 30 patients (average 5-6 days after trauma) and outcome (GOS) was determined after 3 and 12 months. Lesions were classified and lesion volume V was calculated (V = pi abc/6). The applied intracerebral lesion score included lesions in the frontal cortex, basal ganglia, corpus callosum and brainstem. Patients in a persistent vegetative state (PVS) showed a higher number (p = 0.018) and volume (p = 0.013) of frontal lesions as compared to the non-vegetative group (NPVS). Lesion volume in basal ganglia differed significantly between PVS and NPVS (p = 0.01) and correlated to outcome (r = -0.65, p < 0.005). Volume difference in the corpus callosum between PVS and NPVS was significant (p = 0.02). The number (r = -0.61, p < 0.005) and volume (r = -0.62, p < 0.005) of brainstem lesions correlated to outcome and PVS differed in number (p = 0.012) and volume (p = 0.006). The intracerebral lesion score correlated to the GOS (r = -0.57, p = 0.001) and PVS and NPVS differed significantly. A lesion volume exceeding 40 ml in the frontal cortex, 3.5 ml in the basal ganglia, 4 ml in the corpus callosum or 1.5 ml in the brainstem is likely to lead to an unfavorable outcome. More than 4 lesions in the frontal cortex or 3 lesions in the brainstem appeared more frequent in patients with unfavorable outcome. Treatment strategies in the early phase after brain injury could be modified by the knowledge of certain lesions only visible on MRI.