Brain macrophages in human cortical contusions as indicator of survival period.

The aim of this study was to establish a morphologic time scheme with which cases of cerebral contusion with unknown survival periods can be dated. Our study of 275 cases was limited to qualitative and quantitative changes in macrophages. The appearance of macrophages and their distribution as well as their content of neutral fat, esterified cholesterol, erythrocytes, siderin, hematoidin, and ceroid were correlated with the survival period. For each cytologic criterium, the observation period, distribution-free limits of tolerance, and relative frequency of identification in different survival periods were determined, and the limits of confidence calculated. The findings permit the dating of trauma in cases with unknown survival periods. Moreover, the probability of this dating was calculated.