Timing of cortical contusion

Summary One hundred and sixteen cases with known intervals between the time of brain injury and the time of death were systematically examined for selected histologic alterations in an attempt to facilitate the timing of histomorphologic alterations in cortical contusions following closed brain injury. The following criteria were considered: erythrocytes, polymorphonuclear leukocytes, scavenger cells, hemosiderophages, lymphocytes, hematoidin, degenerating neurons, neuronophagy, axonal swelling, protoplasmic astrocytes, piloid astrocytes, siderin-containing astrocytes, edema, increase of vessels, fibroblasts/fibrocytes, and collagenous fibers. The post-traumatic interval ranged between 0 min and 58 years.Following routine staining, the paraffin sections were evaluated, and the presence of the selected histomorphologic criteria was determined (i.e., the time at which the criteria were demonstrable for the first and the last time during the post-traumatic interval in cases with different times of post-traumatic survival). The relative frequency of those cases with positive findings was calculated for each criterium in each observation period. The limits of confidence for the respective relative frequency was estimated with a statistical reliability of 95% according to Clopper and Pearson (1934) in the cases with demonstrated individual histomorphologic criteria. The distribution-free tolerance intervals with which each histomorphologic criterium is to be expected with 95% reliability within the observation period were established. The statistical data were compared with some of the data presented in the literature.